Linux 4.19.124

Makefile: disallow data races on gcc-10 as well

commit b1112139a103b4b1101d0d2d72931f2d33d8c978 upstream.

gcc-10 will rename --param=allow-store-data-races=0
to -fno-allow-store-data-races.

The flag change happened at https://gcc.gnu.org/PR92046.

Signed-off-by: Sergei Trofimovich <slyfox@gentoo.org>
Acked-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Cc: Thomas Backlund <tmb@mageia.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

KVM: x86: Fix off-by-one error in kvm_vcpu_ioctl_x86_setup_mce

commit c4e0e4ab4cf3ec2b3f0b628ead108d677644ebd9 upstream.

Bank_num is a one-based count of banks, not a zero-based index. It
overflows the allocated space only when strictly greater than
KVM_MAX_MCE_BANKS.

Fixes: a9e38c3e01ad ("KVM: x86: Catch potential overrun in MCE setup")
Signed-off-by: Jue Wang <juew@google.com>
Signed-off-by: Jim Mattson <jmattson@google.com>
Reviewed-by: Peter Shier <pshier@google.com>
Message-Id: <20200511225616.19557-1-jmattson@google.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: dts: r8a7740: Add missing extal2 to CPG node

commit e47cb97f153193d4b41ca8d48127da14513d54c7 upstream.

The Clock Pulse Generator (CPG) device node lacks the extal2 clock.
This may lead to a failure registering the "r" clock, or to a wrong
parent for the "usb24s" clock, depending on MD_CK2 pin configuration and
boot loader CPG_USBCKCR register configuration.

This went unnoticed, as this does not affect the single upstream board
configuration, which relies on the first clock input only.

Fixes: d9ffd583bf345e2e ("ARM: shmobile: r8a7740: add SoC clocks to DTS")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Ulrich Hecht <uli+renesas@fpond.eu>
Link: https://lore.kernel.org/r/20200508095918.6061-1-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arm64: dts: renesas: r8a77980: Fix IPMMU VIP[01] nodes

commit f4d71c6ea9e58c07dd4d02d09c5dd9bb780ec4b1 upstream.

Missing the renesas,ipmmu-main property on ipmmu_vip[01] nodes.

Fixes: 55697cbb44e4 ("arm64: dts: renesas: r8a779{65,80,90}: Add IPMMU devices nodes)
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Link: https://lore.kernel.org/r/1587108543-23786-1-git-send-email-yoshihiro.shimoda.uh@renesas.com
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: dts: r8a73a4: Add missing CMT1 interrupts

commit 0f739fdfe9e5ce668bd6d3210f310df282321837 upstream.

The R-Mobile APE6 Compare Match Timer 1 generates 8 interrupts, one for
each channel, but currently only 1 is described.
Fix this by adding the missing interrupts.

Fixes: f7b65230019b9dac ("ARM: shmobile: r8a73a4: Add CMT1 node")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://lore.kernel.org/r/20200408090926.25201-1-geert+renesas@glider.be
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arm64: dts: rockchip: Rename dwc3 device nodes on rk3399 to make dtc happy

commit 190c7f6fd43a776d4a6da1dac44408104649e9b7 upstream.

The device tree compiler complains that the dwc3 nodes have regs
properties but no matching unit addresses.

Add the unit addresses to the device node name. While at it, also rename
the nodes from "dwc3" to "usb", as guidelines require device nodes have
generic names.

Fixes: 7144224f2c2b ("arm64: dts: rockchip: support dwc3 USB for rk3399")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Link: https://lore.kernel.org/r/20200327030414.5903-7-wens@kernel.org
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

arm64: dts: rockchip: Replace RK805 PMIC node name with "pmic" on rk3328 boards

commit 83b994129fb4c18a8460fd395864a28740e5e7fb upstream.

In some board device tree files, "rk805" was used for the RK805 PMIC's
node name. However the policy for device trees is that generic names
should be used.

Replace the "rk805" node name with the generic "pmic" name.

Fixes: 1e28037ec88e ("arm64: dts: rockchip: add rk805 node for rk3328-evb")
Fixes: 955bebde057e ("arm64: dts: rockchip: add rk3328-rock64 board")
Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Link: https://lore.kernel.org/r/20200327030414.5903-3-wens@kernel.org
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

clk: Unlink clock if failed to prepare or enable

commit 018d4671b9bbd4a5c55cf6eab3e1dbc70a50b66e upstream.

On failing to prepare or enable a clock, remove the core structure
from the list it has been inserted as it is about to be freed.

This otherwise leads to random crashes when subsequent clocks get
registered, during which parsing of the clock tree becomes adventurous.

Observed with QEMU's RPi-3 emulation.

Fixes: 12ead77432f2 ("clk: Don't try to enable critical clocks if prepare failed")
Signed-off-by: Marc Zyngier <maz@kernel.org>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Michael Turquette <mturquette@baylibre.com>
Link: https://lkml.kernel.org/r/20200505140953.409430-1-maz@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Revert "ALSA: hda/realtek: Fix pop noise on ALC225"

commit f41224efcf8aafe80ea47ac870c5e32f3209ffc8 upstream.

This reverts commit 3b36b13d5e69d6f51ff1c55d1b404a74646c9757.

Enable power save node breaks some systems with ACL225. Revert the patch
and use a platform specific quirk for the original issue isntead.

Fixes: 3b36b13d5e69 ("ALSA: hda/realtek: Fix pop noise on ALC225")
BugLink: https://bugs.launchpad.net/bugs/1875916
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Link: https://lore.kernel.org/r/20200503152449.22761-1-kai.heng.feng@canonical.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: legacy: fix error return code in cdc_bind()

commit e8f7f9e3499a6d96f7f63a4818dc7d0f45a7783b upstream.

If 'usb_otg_descriptor_alloc()' fails, we must return a
negative error code -ENOMEM, not 0.

Fixes: ab6796ae9833 ("usb: gadget: cdc2: allocate and init otg descriptor by otg capabilities")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: legacy: fix error return code in gncm_bind()

commit e27d4b30b71c66986196d8a1eb93cba9f602904a upstream.

If 'usb_otg_descriptor_alloc()' fails, we must return a
negative error code -ENOMEM, not 0.

Fixes: 1156e91dd7cc ("usb: gadget: ncm: allocate and init otg descriptor by otg capabilities")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: audio: Fix a missing error return value in audio_bind()

commit 19b94c1f9c9a16d41a8de3ccbdb8536cf1aecdbf upstream.

If 'usb_otg_descriptor_alloc()' fails, we must return an error code, not 0.

Fixes: 56023ce0fd70 ("usb: gadget: audio: allocate and init otg descriptor by otg capabilities")
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: gadget: net2272: Fix a memory leak in an error handling path in 'net2272_plat_probe()'

commit ccaef7e6e354fb65758eaddd3eae8065a8b3e295 upstream.

'dev' is allocated in 'net2272_probe_init()'. It must be freed in the error
handling path, as already done in the remove function (i.e.
'net2272_plat_remove()')

Fixes: 90fccb529d24 ("usb: gadget: Gadget directory cleanup - group UDC drivers")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

dwc3: Remove check for HWO flag in dwc3_gadget_ep_reclaim_trb_sg()

commit 00e21763f2c8cab21b7befa52996d1b18bde5c42 upstream.

The check for the HWO flag in dwc3_gadget_ep_reclaim_trb_sg()
causes us to break out of the loop before we call
dwc3_gadget_ep_reclaim_completed_trb(), which is what likely
should be clearing the HWO flag.

This can cause odd behavior where we never reclaim all the trbs
in the sg list, so we never call giveback on a usb req, and that
will causes transfer stalls.

This effectively resovles the adb stalls seen on HiKey960
after userland changes started only using AIO in adbd.

Cc: YongQin Liu <yongqin.liu@linaro.org>
Cc: Anurag Kumar Vulisha <anurag.kumar.vulisha@xilinx.com>
Cc: Yang Fei <fei.yang@intel.com>
Cc: Thinh Nguyen <thinhn@synopsys.com>
Cc: Tejas Joglekar <tejas.joglekar@synopsys.com>
Cc: Andrzej Pietrasiewicz <andrzej.p@collabora.com>
Cc: Jack Pham <jackp@codeaurora.org>
Cc: Josh Gao <jmgao@google.com>
Cc: Todd Kjos <tkjos@google.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-usb@vger.kernel.org
Cc: stable@vger.kernel.org #4.20+
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Felipe Balbi <balbi@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

clk: rockchip: fix incorrect configuration of rk3228 aclk_gpu* clocks

commit cec9d101d70a3509da9bd2e601e0b242154ce616 upstream.

The following changes prevent the unrecoverable freezes and rcu_sched
stall warnings experienced in each of my attempts to take advantage of
lima.

Replace the COMPOSITE_NOGATE definition of aclk_gpu_pre with a
COMPOSITE that retains the selection of HDMIPHY as the PLL source, but
instead makes uses of the aclk_gpu PLL source gate and parent names
defined by mux_pll_src_4plls_p rather than mux_aclk_gpu_pre_p.

Remove the now unused mux_aclk_gpu_pre_p and the four named but also
unused definitions (cpll_gpu, gpll_gpu, hdmiphy_gpu and usb480m_gpu)
of the aclk_gpu PLL source gate.

Use the correct gate offset for aclk_gpu and aclk_gpu_noc.

Fixes: 307a2e9ac524 ("clk: rockchip: add clock controller for rk3228")
Cc: stable@vger.kernel.org
Signed-off-by: Justin Swartz <justin.swartz@risingedge.co.za>
[double-checked against SoC manual and added fixes tag]
Link: https://lore.kernel.org/r/20200114162503.7548-1-justin.swartz@risingedge.co.za
Signed-off-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

exec: Move would_dump into flush_old_exec

commit f87d1c9559164294040e58f5e3b74a162bf7c6e8 upstream.

I goofed when I added mm->user_ns support to would_dump.  I missed the
fact that in the case of binfmt_loader, binfmt_em86, binfmt_misc, and
binfmt_script bprm->file is reassigned.  Which made the move of
would_dump from setup_new_exec to __do_execve_file before exec_binprm
incorrect as it can result in would_dump running on the script instead
of the interpreter of the script.

The net result is that the code stopped making unreadable interpreters
undumpable.  Which allows them to be ptraced and written to disk
without special permissions.  Oops.

The move was necessary because the call in set_new_exec was after
bprm->mm was no longer valid.

To correct this mistake move the misplaced would_dump from
__do_execve_file into flos_old_exec, before exec_mmap is called.

I tested and confirmed that without this fix I can attach with gdb to
a script with an unreadable interpreter, and with this fix I can not.

Cc: stable@vger.kernel.org
Fixes: f84df2a6f268 ("exec: Ensure mm->user_ns contains the execed files")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/unwind/orc: Fix error handling in __unwind_start()

commit 71c95825289f585014fe9741b051d32a7a916680 upstream.

The unwind_state 'error' field is used to inform the reliable unwinding
code that the stack trace can't be trusted.  Set this field for all
errors in __unwind_start().

Also, move the zeroing out of the unwind_state struct to before the ORC
table initialization check, to prevent the caller from reading
uninitialized data if the ORC table is corrupted.

Fixes: af085d9084b4 ("stacktrace/x86: add function for detecting reliable stack traces")
Fixes: d3a09104018c ("x86/unwinder/orc: Dont bail on stack overflow")
Fixes: 98d0c8ebf77e ("x86/unwind/orc: Prevent unwinding before ORC initialization")
Reported-by: Pavel Machek <pavel@denx.de>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/d6ac7215a84ca92b895fdd2e1aa546729417e6e6.1589487277.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86: Fix early boot crash on gcc-10, third try

commit a9a3ed1eff3601b63aea4fb462d8b3b92c7c1e7e upstream.

... or the odyssey of trying to disable the stack protector for the
function which generates the stack canary value.

The whole story started with Sergei reporting a boot crash with a kernel
built with gcc-10:

  Kernel panic — not syncing: stack-protector: Kernel stack is corrupted in: start_secondary
  CPU: 1 PID: 0 Comm: swapper/1 Not tainted 5.6.0-rc5—00235—gfffb08b37df9 #139
  Hardware name: Gigabyte Technology Co., Ltd. To be filled by O.E.M./H77M—D3H, BIOS F12 11/14/2013
  Call Trace:
    dump_stack
    panic
    ? start_secondary
    __stack_chk_fail
    start_secondary
    secondary_startup_64
  -—-[ end Kernel panic — not syncing: stack—protector: Kernel stack is corrupted in: start_secondary

This happens because gcc-10 tail-call optimizes the last function call
in start_secondary() - cpu_startup_entry() - and thus emits a stack
canary check which fails because the canary value changes after the
boot_init_stack_canary() call.

To fix that, the initial attempt was to mark the one function which
generates the stack canary with:

  __attribute__((optimize("-fno-stack-protector"))) ... start_secondary(void *unused)

however, using the optimize attribute doesn't work cumulatively
as the attribute does not add to but rather replaces previously
supplied optimization options - roughly all -fxxx options.

The key one among them being -fno-omit-frame-pointer and thus leading to
not present frame pointer - frame pointer which the kernel needs.

The next attempt to prevent compilers from tail-call optimizing
the last function call cpu_startup_entry(), shy of carving out
start_secondary() into a separate compilation unit and building it with
-fno-stack-protector, was to add an empty asm("").

This current solution was short and sweet, and reportedly, is supported
by both compilers but we didn't get very far this time: future (LTO?)
optimization passes could potentially eliminate this, which leads us
to the third attempt: having an actual memory barrier there which the
compiler cannot ignore or move around etc.

That should hold for a long time, but hey we said that about the other
two solutions too so...

Reported-by: Sergei Trofimovich <slyfox@gentoo.org>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Kalle Valo <kvalo@codeaurora.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200314164451.346497-1-slyfox@gentoo.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

cifs: fix leaked reference on requeued write

commit a48137996063d22ffba77e077425f49873856ca5 upstream.

Failed async writes that are requeued may not clean up a refcount
on the file, which can result in a leaked open. This scenario arises
very reliably when using persistent handles and a reconnect occurs
while writing.

cifs_writev_requeue only releases the reference if the write fails
(rc != 0). The server->ops->async_writev operation will take its own
reference, so the initial reference can always be released.

Signed-off-by: Adam McCoy <adam@forsedomani.com>
Signed-off-by: Steve French <stfrench@microsoft.com>
CC: Stable <stable@vger.kernel.org>
Reviewed-by: Pavel Shilovsky <pshilov@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: dts: imx27-phytec-phycard-s-rdk: Fix the I2C1 pinctrl entries

commit 0caf34350a25907515d929a9c77b9b206aac6d1e upstream.

The I2C2 pins are already used and the following errors are seen:

imx27-pinctrl 10015000.iomuxc: pin MX27_PAD_I2C2_SDA already requested by 10012000.i2c; cannot claim for 1001d000.i2c
imx27-pinctrl 10015000.iomuxc: pin-69 (1001d000.i2c) status -22
imx27-pinctrl 10015000.iomuxc: could not request pin 69 (MX27_PAD_I2C2_SDA) from group i2c2grp  on device 10015000.iomuxc
imx-i2c 1001d000.i2c: Error applying setting, reverse things back
imx-i2c: probe of 1001d000.i2c failed with error -22

Fix it by adding the correct I2C1 IOMUX entries for the pinctrl_i2c1 group.

Cc: <stable@vger.kernel.org>
Fixes: 61664d0b432a ("ARM: dts: imx27 phyCARD-S pinctrl")
Signed-off-by: Fabio Estevam <festevam@gmail.com>
Reviewed-by: Stefan Riedmueller <s.riedmueller@phytec.de>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ARM: dts: dra7: Fix bus_dma_limit for PCIe

commit 90d4d3f4ea45370d482fa609dbae4d2281b4074f upstream.

Even though commit cfb5d65f2595 ("ARM: dts: dra7: Add bus_dma_limit
for L3 bus") added bus_dma_limit for L3 bus, the PCIe controller
gets incorrect value of bus_dma_limit.

Fix it by adding empty dma-ranges property to axi@0 and axi@1
(parent device tree node of PCIe controller).

Cc: stable@kernel.org
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: xhci: Fix NULL pointer dereference when enqueuing trbs from urb sg list

commit 3c6f8cb92c9178fc0c66b580ea3df1fa3ac1155a upstream.

On platforms with IOMMU enabled, multiple SGs can be coalesced into one
by the IOMMU driver. In that case the SG list processing as part of the
completion of a urb on a bulk endpoint can result into a NULL pointer
dereference with the below stack dump.

<6> Unable to handle kernel NULL pointer dereference at virtual address 0000000c
<6> pgd = c0004000
<6> [0000000c] *pgd=00000000
<6> Internal error: Oops: 5 [#1] PREEMPT SMP ARM
<2> PC is at xhci_queue_bulk_tx+0x454/0x80c
<2> LR is at xhci_queue_bulk_tx+0x44c/0x80c
<2> pc : [<c08907c4>]    lr : [<c08907bc>]    psr: 000000d3
<2> sp : ca337c80  ip : 00000000  fp : ffffffff
<2> r10: 00000000  r9 : 50037000  r8 : 00004000
<2> r7 : 00000000  r6 : 00004000  r5 : 00000000  r4 : 00000000
<2> r3 : 00000000  r2 : 00000082  r1 : c2c1a200  r0 : 00000000
<2> Flags: nzcv  IRQs off  FIQs off  Mode SVC_32  ISA ARM  Segment none
<2> Control: 10c0383d  Table: b412c06a  DAC: 00000051
<6> Process usb-storage (pid: 5961, stack limit = 0xca336210)
<snip>
<2> [<c08907c4>] (xhci_queue_bulk_tx)
<2> [<c0881b3c>] (xhci_urb_enqueue)
<2> [<c0831068>] (usb_hcd_submit_urb)
<2> [<c08350b4>] (usb_sg_wait)
<2> [<c089f384>] (usb_stor_bulk_transfer_sglist)
<2> [<c089f2c0>] (usb_stor_bulk_srb)
<2> [<c089fe38>] (usb_stor_Bulk_transport)
<2> [<c089f468>] (usb_stor_invoke_transport)
<2> [<c08a11b4>] (usb_stor_control_thread)
<2> [<c014a534>] (kthread)

The above NULL pointer dereference is the result of block_len and the
sent_len set to zero after the first SG of the list when IOMMU driver
is enabled. Because of this the loop of processing the SGs has run
more than num_sgs which resulted in a sg_next on the last SG of the
list which has SG_END set.

Fix this by check for the sg before any attributes of the sg are
accessed.

[modified reason for null pointer dereference in commit message subject -Mathias]
Fixes: f9c589e142d04 ("xhci: TD-fragment, align the unsplittable case with a bounce buffer")
Cc: stable@vger.kernel.org
Signed-off-by: Sriharsha Allenki <sallenki@codeaurora.org>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200514110432.25564-2-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

USB: gadget: fix illegal array access in binding with UDC

commit 15753588bcd4bbffae1cca33c8ced5722477fe1f upstream.

FuzzUSB (a variant of syzkaller) found an illegal array access
using an incorrect index while binding a gadget with UDC.

Reference: https://www.spinics.net/lists/linux-usb/msg194331.html

This bug occurs when a size variable used for a buffer
is misused to access its strcpy-ed buffer.
Given a buffer along with its size variable (taken from user input),
from which, a new buffer is created using kstrdup().
Due to the original buffer containing 0 value in the middle,
the size of the kstrdup-ed buffer becomes smaller than that of the original.
So accessing the kstrdup-ed buffer with the same size variable
triggers memory access violation.

The fix makes sure no zero value in the buffer,
by comparing the strlen() of the orignal buffer with the size variable,
so that the access to the kstrdup-ed buffer is safe.

BUG: KASAN: slab-out-of-bounds in gadget_dev_desc_UDC_store+0x1ba/0x200
drivers/usb/gadget/configfs.c:266
Read of size 1 at addr ffff88806a55dd7e by task syz-executor.0/17208

CPU: 2 PID: 17208 Comm: syz-executor.0 Not tainted 5.6.8 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0xce/0x128 lib/dump_stack.c:118
 print_address_description.constprop.4+0x21/0x3c0 mm/kasan/report.c:374
 __kasan_report+0x131/0x1b0 mm/kasan/report.c:506
 kasan_report+0x12/0x20 mm/kasan/common.c:641
 __asan_report_load1_noabort+0x14/0x20 mm/kasan/generic_report.c:132
 gadget_dev_desc_UDC_store+0x1ba/0x200 drivers/usb/gadget/configfs.c:266
 flush_write_buffer fs/configfs/file.c:251 [inline]
 configfs_write_file+0x2f1/0x4c0 fs/configfs/file.c:283
 __vfs_write+0x85/0x110 fs/read_write.c:494
 vfs_write+0x1cd/0x510 fs/read_write.c:558
 ksys_write+0x18a/0x220 fs/read_write.c:611
 __do_sys_write fs/read_write.c:623 [inline]
 __se_sys_write fs/read_write.c:620 [inline]
 __x64_sys_write+0x73/0xb0 fs/read_write.c:620
 do_syscall_64+0x9e/0x510 arch/x86/entry/common.c:294
 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Signed-off-by: Kyungtae Kim <kt0755@gmail.com>
Reported-and-tested-by: Kyungtae Kim <kt0755@gmail.com>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: stable <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200510054326.GA19198@pizza01
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: host: xhci-plat: keep runtime active when removing host

commit 1449cb2c2253d37d998c3714aa9b95416d16d379 upstream.

While removing the host (e.g. for USB role switch from host to device),
if runtime pm is enabled by user, below oops occurs on dwc3 and cdns3
platforms.
Keeping the xhci-plat device active during host removal, and disabling
runtime pm before calling pm_runtime_set_suspended() fixes them.

oops1:
Unable to handle kernel NULL pointer dereference at virtual address
0000000000000240
Internal error: Oops: 96000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 0 PID: 5 Comm: kworker/0:0 Not tainted 5.4.3-00107-g64d454a-dirty
Hardware name: FSL i.MX8MP EVK (DT)
Workqueue: pm pm_runtime_work
pstate: 60000005 (nZCv daif -PAN -UAO)
pc : xhci_suspend+0x34/0x698
lr : xhci_plat_runtime_suspend+0x2c/0x38
sp : ffff800011ddbbc0
Call trace:
 xhci_suspend+0x34/0x698
 xhci_plat_runtime_suspend+0x2c/0x38
 pm_generic_runtime_suspend+0x28/0x40
 __rpm_callback+0xd8/0x138
 rpm_callback+0x24/0x98
 rpm_suspend+0xe0/0x448
 rpm_idle+0x124/0x140
 pm_runtime_work+0xa0/0xf8
 process_one_work+0x1dc/0x370
 worker_thread+0x48/0x468
 kthread+0xf0/0x120
 ret_from_fork+0x10/0x1c

oops2:
usb 2-1: USB disconnect, device number 2
xhci-hcd xhci-hcd.1.auto: remove, state 4
usb usb2: USB disconnect, device number 1
xhci-hcd xhci-hcd.1.auto: USB bus 2 deregistered
xhci-hcd xhci-hcd.1.auto: remove, state 4
usb usb1: USB disconnect, device number 1
Unable to handle kernel NULL pointer dereference at virtual address
0000000000000138
Internal error: Oops: 96000004 [#1] PREEMPT SMP
Modules linked in:
CPU: 2 PID: 7 Comm: kworker/u8:0 Not tainted 5.6.0-rc4-next-20200304-03578
Hardware name: Freescale i.MX8QXP MEK (DT)
Workqueue: 1-0050 tcpm_state_machine_work
pstate: 20000005 (nzCv daif -PAN -UAO)
pc : xhci_free_dev+0x214/0x270
lr : xhci_plat_runtime_resume+0x78/0x88
sp : ffff80001006b5b0
Call trace:
 xhci_free_dev+0x214/0x270
 xhci_plat_runtime_resume+0x78/0x88
 pm_generic_runtime_resume+0x30/0x48
 __rpm_callback+0x90/0x148
 rpm_callback+0x28/0x88
 rpm_resume+0x568/0x758
 rpm_resume+0x260/0x758
 rpm_resume+0x260/0x758
 __pm_runtime_resume+0x40/0x88
 device_release_driver_internal+0xa0/0x1c8
 device_release_driver+0x1c/0x28
 bus_remove_device+0xd4/0x158
 device_del+0x15c/0x3a0
 usb_disable_device+0xb0/0x268
 usb_disconnect+0xcc/0x300
 usb_remove_hcd+0xf4/0x1dc
 xhci_plat_remove+0x78/0xe0
 platform_drv_remove+0x30/0x50
 device_release_driver_internal+0xfc/0x1c8
 device_release_driver+0x1c/0x28
 bus_remove_device+0xd4/0x158
 device_del+0x15c/0x3a0
 platform_device_del.part.0+0x20/0x90
 platform_device_unregister+0x28/0x40
 cdns3_host_exit+0x20/0x40
 cdns3_role_stop+0x60/0x90
 cdns3_role_set+0x64/0xd8
 usb_role_switch_set_role.part.0+0x3c/0x68
 usb_role_switch_set_role+0x20/0x30
 tcpm_mux_set+0x60/0xf8
 tcpm_reset_port+0xa4/0xf0
 tcpm_detach.part.0+0x28/0x50
 tcpm_state_machine_work+0x12ac/0x2360
 process_one_work+0x1c8/0x470
 worker_thread+0x50/0x428
 kthread+0xfc/0x128
 ret_from_fork+0x10/0x18
Code: c8037c02 35ffffa3 17ffe7c3 f9800011 (c85f7c01)
---[ end trace 45b1a173d2679e44 ]---

[minor commit message cleanup  -Mathias]
Cc: Baolin Wang <baolin.wang@linaro.org>
Cc: <stable@vger.kernel.org>
Fixes: b0c69b4bace3 ("usb: host: plat: Enable xHCI plat runtime PM")
Reviewed-by: Peter Chen <peter.chen@nxp.com>
Tested-by: Peter Chen <peter.chen@nxp.com>
Signed-off-by: Li Jun <jun.li@nxp.com>
Signed-off-by: Mathias Nyman <mathias.nyman@linux.intel.com>
Link: https://lore.kernel.org/r/20200514110432.25564-3-mathias.nyman@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

usb: core: hub: limit HUB_QUIRK_DISABLE_AUTOSUSPEND to USB5534B

commit 76e1ef1d81a4129d7e2fb8c48c83b166d1c8e040 upstream.

On Tue, May 12, 2020 at 09:36:07PM +0800, Kai-Heng Feng wrote [1]:
> This patch prevents my Raven Ridge xHCI from getting runtime suspend.

The problem described in v5.6 commit 1208f9e1d758c9 ("USB: hub: Fix the
broken detection of USB3 device in SMSC hub") applies solely to the
USB5534B hub [2] present on the Kingfisher Infotainment Carrier Board,
manufactured by Shimafuji Electric Inc [3].

Despite that, the aforementioned commit applied the quirk to _all_ hubs
carrying vendor ID 0x424 (i.e. SMSC), of which there are more [4] than
initially expected. Consequently, the quirk is now enabled on platforms
carrying SMSC/Microchip hub models which potentially don't exhibit the
original issue.

To avoid reports like [1], further limit the quirk's scope to
USB5534B [2], by employing both Vendor and Product ID checks.

Tested on H3ULCB + Kingfisher rev. M05.

[1] https://lore.kernel.org/linux-renesas-soc/73933975-6F0E-40F5-9584-D2B8F615C0F3@canonical.com/
[2] https://www.microchip.com/wwwproducts/en/USB5534B
[3] http://www.shimafuji.co.jp/wp/wp-content/uploads/2018/08/SBEV-RCAR-KF-M06Board_HWSpecificationEN_Rev130.pdf
[4] https://devicehunt.com/search/type/usb/vendor/0424/device/any

Fixes: 1208f9e1d758c9 ("USB: hub: Fix the broken detection of USB3 device in SMSC hub")
Cc: stable@vger.kernel.org # v4.14+
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Hardik Gajjar <hgajjar@de.adit-jv.com>
Cc: linux-renesas-soc@vger.kernel.org
Cc: linux-usb@vger.kernel.org
Reported-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Signed-off-by: Eugeniu Rosca <erosca@de.adit-jv.com>
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Link: https://lore.kernel.org/r/20200514220246.13290-1-erosca@de.adit-jv.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ALSA: usb-audio: Add control message quirk delay for Kingston HyperX headset

commit 073919e09ca445d4486968e3f851372ff44cf2b5 upstream.

Kingston HyperX headset with 0951:16ad also needs the same quirk for
delaying the frequency controls.

Signed-off-by: Jesus Ramos <jesus-ramos@live.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/BY5PR19MB3634BA68C7CCA23D8DF428E796AF0@BY5PR19MB3634.namprd19.prod.outlook.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ALSA: rawmidi: Fix racy buffer resize under concurrent accesses

commit c1f6e3c818dd734c30f6a7eeebf232ba2cf3181d upstream.

The rawmidi core allows user to resize the runtime buffer via ioctl,
and this may lead to UAF when performed during concurrent reads or
writes: the read/write functions unlock the runtime lock temporarily
during copying form/to user-space, and that's the race window.

This patch fixes the hole by introducing a reference counter for the
runtime buffer read/write access and returns -EBUSY error when the
resize is performed concurrently against read/write.

Note that the ref count field is a simple integer instead of
refcount_t here, since the all contexts accessing the buffer is
basically protected with a spinlock, hence we need no expensive atomic
ops.  Also, note that this busy check is needed only against read /
write functions, and not in receive/transmit callbacks; the race can
happen only at the spinlock hole mentioned in the above, while the
whole function is protected for receive / transmit callbacks.

Reported-by: butt3rflyh4ck <butterflyhuangxx@gmail.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/CAFcO6XMWpUVK_yzzCpp8_XP7+=oUpQvuBeCbMffEDkpe8jWrfg@mail.gmail.com
Link: https://lore.kernel.org/r/s5heerw3r5z.wl-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

ALSA: hda/realtek - Limit int mic boost for Thinkpad T530

commit b590b38ca305d6d7902ec7c4f7e273e0069f3bcc upstream.

Lenovo Thinkpad T530 seems to have a sensitive internal mic capture
that needs to limit the mic boost like a few other Thinkpad models.
Although we may change the quirk for ALC269_FIXUP_LENOVO_DOCK, this
hits way too many other laptop models, so let's add a new fixup model
that limits the internal mic boost on top of the existing quirk and
apply to only T530.

BugLink: https://bugzilla.suse.com/show_bug.cgi?id=1171293
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/20200514160533.10337-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

gcc-10: avoid shadowing standard library 'free()' in crypto

commit 1a263ae60b04de959d9ce9caea4889385eefcc7b upstream.

gcc-10 has started warning about conflicting types for a few new
built-in functions, particularly 'free()'.

This results in warnings like:

   crypto/xts.c:325:13: warning: conflicting types for built-in function ‘free’; expected ‘void(void *)’ [-Wbuiltin-declaration-mismatch]

because the crypto layer had its local freeing functions called
'free()'.

Gcc-10 is in the wrong here, since that function is marked 'static', and
thus there is no chance of confusion with any standard library function
namespace.

But the simplest thing to do is to just use a different name here, and
avoid this gcc mis-feature.

[ Side note: gcc knowing about 'free()' is in itself not the
  mis-feature: the semantics of 'free()' are special enough that a
  compiler can validly do special things when seeing it.

  So the mis-feature here is that gcc thinks that 'free()' is some
  restricted name, and you can't shadow it as a local static function.

  Making the special 'free()' semantics be a function attribute rather
  than tied to the name would be the much better model ]

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

gcc-10: disable 'restrict' warning for now

commit adc71920969870dfa54e8f40dac8616284832d02 upstream.

gcc-10 now warns about passing aliasing pointers to functions that take
restricted pointers.

That's actually a great warning, and if we ever start using 'restrict'
in the kernel, it might be quite useful.  But right now we don't, and it
turns out that the only thing this warns about is an idiom where we have
declared a few functions to be "printf-like" (which seems to make gcc
pick up the restricted pointer thing), and then we print to the same
buffer that we also use as an input.

And people do that as an odd concatenation pattern, with code like this:

    #define sysfs_show_gen_prop(buffer, fmt, ...) \
        snprintf(buffer, PAGE_SIZE, "%s"fmt, buffer, __VA_ARGS__)

where we have 'buffer' as both the destination of the final result, and
as the initial argument.

Yes, it's a bit questionable.  And outside of the kernel, people do have
standard declarations like

    int snprintf( char *restrict buffer, size_t bufsz,
                  const char *restrict format, ... );

where that output buffer is marked as a restrict pointer that cannot
alias with any other arguments.

But in the context of the kernel, that 'use snprintf() to concatenate to
the end result' does work, and the pattern shows up in multiple places.
And we have not marked our own version of snprintf() as taking restrict
pointers, so the warning is incorrect for now, and gcc picks it up on
its own.

If we do start using 'restrict' in the kernel (and it might be a good
idea if people find places where it matters), we'll need to figure out
how to avoid this issue for snprintf and friends.  But in the meantime,
this warning is not useful.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

gcc-10: disable 'stringop-overflow' warning for now

commit 5a76021c2eff7fcf2f0918a08fd8a37ce7922921 upstream.

This is the final array bounds warning removal for gcc-10 for now.

Again, the warning is good, and we should re-enable all these warnings
when we have converted all the legacy array declaration cases to
flexible arrays. But in the meantime, it's just noise.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

gcc-10: disable 'array-bounds' warning for now

commit 44720996e2d79e47d508b0abe99b931a726a3197 upstream.

This is another fine warning, related to the 'zero-length-bounds' one,
but hitting the same historical code in the kernel.

Because C didn't historically support flexible array members, we have
code that instead uses a one-sized array, the same way we have cases of
zero-sized arrays.

The one-sized arrays come from either not wanting to use the gcc
zero-sized array extension, or from a slight convenience-feature, where
particularly for strings, the size of the structure now includes the
allocation for the final NUL character.

So with a "char name[1];" at the end of a structure, you can do things
like

       v = my_malloc(sizeof(struct vendor) + strlen(name));

and avoid the "+1" for the terminator.

Yes, the modern way to do that is with a flexible array, and using
'offsetof()' instead of 'sizeof()', and adding the "+1" by hand.  That
also technically gets the size "more correct" in that it avoids any
alignment (and thus padding) issues, but this is another long-term
cleanup thing that will not happen for 5.7.

So disable the warning for now, even though it's potentially quite
useful.  Having a slew of warnings that then hide more urgent new issues
is not an improvement.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

gcc-10: disable 'zero-length-bounds' warning for now

commit 5c45de21a2223fe46cf9488c99a7fbcf01527670 upstream.

This is a fine warning, but we still have a number of zero-length arrays
in the kernel that come from the traditional gcc extension.  Yes, they
are getting converted to flexible arrays, but in the meantime the gcc-10
warning about zero-length bounds is very verbose, and is hiding other
issues.

I missed one actual build failure because it was hidden among hundreds
of lines of warning.  Thankfully I caught it on the second go before
pushing things out, but it convinced me that I really need to disable
the new warnings for now.

We'll hopefully be all done with our conversion to flexible arrays in
the not too distant future, and we can then re-enable this warning.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Stop the ad-hoc games with -Wno-maybe-initialized

commit 78a5255ffb6a1af189a83e493d916ba1c54d8c75 upstream.

We have some rather random rules about when we accept the
"maybe-initialized" warnings, and when we don't.

For example, we consider it unreliable for gcc versions < 4.9, but also
if -O3 is enabled, or if optimizing for size.  And then various kernel
config options disabled it, because they know that they trigger that
warning by confusing gcc sufficiently (ie PROFILE_ALL_BRANCHES).

And now gcc-10 seems to be introducing a lot of those warnings too, so
it falls under the same heading as 4.9 did.

At the same time, we have a very straightforward way to _enable_ that
warning when wanted: use "W=2" to enable more warnings.

So stop playing these ad-hoc games, and just disable that warning by
default, with the known and straight-forward "if you want to work on the
extra compiler warnings, use W=123".

Would it be great to have code that is always so obvious that it never
confuses the compiler whether a variable is used initialized or not?
Yes, it would.  In a perfect world, the compilers would be smarter, and
our source code would be simpler.

That's currently not the world we live in, though.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

kbuild: compute false-positive -Wmaybe-uninitialized cases in Kconfig

commit b303c6df80c9f8f13785aa83a0471fca7e38b24d upstream.

Since -Wmaybe-uninitialized was introduced by GCC 4.7, we have patched
various false positives:

 - commit e74fc973b6e5 ("Turn off -Wmaybe-uninitialized when building
   with -Os") turned off this option for -Os.

 - commit 815eb71e7149 ("Kbuild: disable 'maybe-uninitialized' warning
   for CONFIG_PROFILE_ALL_BRANCHES") turned off this option for
   CONFIG_PROFILE_ALL_BRANCHES

 - commit a76bcf557ef4 ("Kbuild: enable -Wmaybe-uninitialized warning
   for "make W=1"") turned off this option for GCC < 4.9
   Arnd provided more explanation in https://lkml.org/lkml/2017/3/14/903

I think this looks better by shifting the logic from Makefile to Kconfig.

Link: https://github.com/ClangBuiltLinux/linux/issues/350
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

gcc-10 warnings: fix low-hanging fruit

commit 9d82973e032e246ff5663c9805fbb5407ae932e3 upstream.

Due to a bug-report that was compiler-dependent, I updated one of my
machines to gcc-10.  That shows a lot of new warnings.  Happily they
seem to be mostly the valid kind, but it's going to cause a round of
churn for getting rid of them..

This is the really low-hanging fruit of removing a couple of zero-sized
arrays in some core code.  We have had a round of these patches before,
and we'll have many more coming, and there is nothing special about
these except that they were particularly trivial, and triggered more
warnings than most.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pnp: Use list_for_each_entry() instead of open coding

commit 01b2bafe57b19d9119413f138765ef57990921ce upstream.

Aside from good practice, this avoids a warning from gcc 10:

./include/linux/kernel.h:997:3: warning: array subscript -31 is outside array bounds of ‘struct list_head[1]’ [-Warray-bounds]
  997 |  ((type *)(__mptr - offsetof(type, member))); })
      |  ~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
./include/linux/list.h:493:2: note: in expansion of macro ‘container_of’
  493 |  container_of(ptr, type, member)
      |  ^~~~~~~~~~~~
./include/linux/pnp.h:275:30: note: in expansion of macro ‘list_entry’
  275 | #define global_to_pnp_dev(n) list_entry(n, struct pnp_dev, global_list)
      |                              ^~~~~~~~~~
./include/linux/pnp.h:281:11: note: in expansion of macro ‘global_to_pnp_dev’
  281 |  (dev) != global_to_pnp_dev(&pnp_global); \
      |           ^~~~~~~~~~~~~~~~~
arch/x86/kernel/rtc.c:189:2: note: in expansion of macro ‘pnp_for_each_dev’
  189 |  pnp_for_each_dev(dev) {

Because the common code doesn't cast the starting list_head to the
containing struct.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
[ rjw: Whitespace adjustments ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

hwmon: (da9052) Synchronize access with mfd

[ Upstream commit 333e22db228f0bd0c839553015a6a8d3db4ba569 ]

When tsi-as-adc is configured it is possible for in7[0123]_input read to
return an incorrect value if a concurrent read to in[456]_input is
performed. This is caused by a concurrent manipulation of the mux
channel without proper locking as hwmon and mfd use different locks for
synchronization.

Switch hwmon to use the same lock as mfd when accessing the TSI channel.

Fixes: 4f16cab19a3d5 ("hwmon: da9052: Add support for TSI channel")
Signed-off-by: Samu Nuutamo <samu.nuutamo@vincit.fi>
[rebase to current master, reword commit message slightly]
Signed-off-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

IB/mlx4: Test return value of calls to ib_get_cached_pkey

[ Upstream commit 6693ca95bd4330a0ad7326967e1f9bcedd6b0800 ]

In the mlx4_ib_post_send() flow, some functions call ib_get_cached_pkey()
without checking its return value. If ib_get_cached_pkey() returns an
error code, these functions should return failure.

Fixes: 1ffeb2eb8be9 ("IB/mlx4: SR-IOV IB context objects and proxy/tunnel SQP support")
Fixes: 225c7b1feef1 ("IB/mlx4: Add a driver Mellanox ConnectX InfiniBand adapters")
Fixes: e622f2f4ad21 ("IB: split struct ib_send_wr")
Link: https://lore.kernel.org/r/20200426075921.130074-1-leon@kernel.org
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Leon Romanovsky <leonro@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

netfilter: nft_set_rbtree: Introduce and use nft_rbtree_interval_start()

[ Upstream commit 6f7c9caf017be8ab0fe3b99509580d0793bf0833 ]

Replace negations of nft_rbtree_interval_end() with a new helper,
nft_rbtree_interval_start(), wherever this helps to visualise the
problem at hand, that is, for all the occurrences except for the
comparison against given flags in __nft_rbtree_get().

This gets especially useful in the next patch.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

arm64: fix the flush_icache_range arguments in machine_kexec

[ Upstream commit d51c214541c5154dda3037289ee895ea3ded5ebd ]

The second argument is the end "pointer", not the length.

Fixes: d28f6df1305a ("arm64/kexec: Add core kexec support")
Cc: <stable@vger.kernel.org> # 4.8.x-
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

netfilter: conntrack: avoid gcc-10 zero-length-bounds warning

[ Upstream commit 2c407aca64977ede9b9f35158e919773cae2082f ]

gcc-10 warns around a suspicious access to an empty struct member:

net/netfilter/nf_conntrack_core.c: In function '__nf_conntrack_alloc':
net/netfilter/nf_conntrack_core.c:1522:9: warning: array subscript 0 is outside the bounds of an interior zero-length array 'u8[0]' {aka 'unsigned char[0]'} [-Wzero-length-bounds]
 1522 |  memset(&ct->__nfct_init_offset[0], 0,
      |         ^~~~~~~~~~~~~~~~~~~~~~~~~~
In file included from net/netfilter/nf_conntrack_core.c:37:
include/net/netfilter/nf_conntrack.h:90:5: note: while referencing '__nfct_init_offset'
   90 |  u8 __nfct_init_offset[0];
      |     ^~~~~~~~~~~~~~~~~~

The code is correct but a bit unusual. Rework it slightly in a way that
does not trigger the warning, using an empty struct instead of an empty
array. There are probably more elegant ways to do this, but this is the
smallest change.

Fixes: c41884ce0562 ("netfilter: conntrack: avoid zeroing timer")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

NFSv4: Fix fscache cookie aux_data to ensure change_attr is included

[ Upstream commit 50eaa652b54df1e2b48dc398d9e6114c9ed080eb ]

Commit 402cb8dda949 ("fscache: Attach the index key and aux data to
the cookie") added the aux_data and aux_data_len to parameters to
fscache_acquire_cookie(), and updated the callers in the NFS client.
In the process it modified the aux_data to include the change_attr,
but missed adding change_attr to a couple places where aux_data was
used.  Specifically, when opening a file and the change_attr is not
added, the following attempt to lookup an object will fail inside
cachefiles_check_object_xattr() = -116 due to
nfs_fscache_inode_check_aux() failing memcmp on auxdata and returning
FSCACHE_CHECKAUX_OBSOLETE.

Fix this by adding nfs_fscache_update_auxdata() to set the auxdata
from all relevant fields in the inode, including the change_attr.

Fixes: 402cb8dda949 ("fscache: Attach the index key and aux data to the cookie")
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

nfs: fscache: use timespec64 in inode auxdata

[ Upstream commit 6e31ded6895adfca97211118cc9b72236e8f6d53 ]

nfs currently behaves differently on 32-bit and 64-bit kernels regarding
the on-disk format of nfs_fscache_inode_auxdata.

That format should really be the same on any kernel, and we should avoid
the 'timespec' type in order to remove that from the kernel later on.

Using plain 'timespec64' would not be good here, since that includes
implied padding and would possibly leak kernel stack data to the on-disk
format on 32-bit architectures.

struct __kernel_timespec would work as a replacement, but open-coding
the two struct members in nfs_fscache_inode_auxdata makes it more
obvious what's going on here, and keeps the current format for 64-bit
architectures.

Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

NFS: Fix fscache super_cookie index_key from changing after umount

[ Upstream commit d9bfced1fbcb35b28d8fbed4e785d2807055ed2b ]

Commit 402cb8dda949 ("fscache: Attach the index key and aux data to
the cookie") added the index_key and index_key_len parameters to
fscache_acquire_cookie(), and updated the callers in the NFS client.
One of the callers was inside nfs_fscache_get_super_cookie()
and was changed to use the full struct nfs_fscache_key as the
index_key.  However, a couple members of this structure contain
pointers and thus will change each time the same NFS share is
remounted.  Since index_key is used for fscache_cookie->key_hash
and this subsequently is used to compare cookies, the effectiveness
of fscache with NFS is reduced to the point at which a umount
occurs.   Any subsequent remount of the same share will cause a
unique NFS super_block index_key and key_hash to be generated for
the same data, rendering any prior fscache data unable to be
found.  A simple reproducer demonstrates the problem.

1. Mount share with 'fsc', create a file, drop page cache
systemctl start cachefilesd
mount -o vers=3,fsc 127.0.0.1:/export /mnt
dd if=/dev/zero of=/mnt/file1.bin bs=4096 count=1
echo 3 > /proc/sys/vm/drop_caches

2. Read file into page cache and fscache, then unmount
dd if=/mnt/file1.bin of=/dev/null bs=4096 count=1
umount /mnt

3. Remount and re-read which should come from fscache
mount -o vers=3,fsc 127.0.0.1:/export /mnt
echo 3 > /proc/sys/vm/drop_caches
dd if=/mnt/file1.bin of=/dev/null bs=4096 count=1

4. Check for READ ops in mountstats - there should be none
grep READ: /proc/self/mountstats

Looking at the history and the removed function, nfs_super_get_key(),
we should only use nfs_fscache_key.key plus any uniquifier, for
the fscache index_key.

Fixes: 402cb8dda949 ("fscache: Attach the index key and aux data to the cookie")
Signed-off-by: Dave Wysochanski <dwysocha@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

mmc: block: Fix request completion in the CQE timeout path

[ Upstream commit c077dc5e0620508a29497dac63a2822324ece52a ]

First, it should be noted that the CQE timeout (60 seconds) is substantial
so a CQE request that times out is really stuck, and the race between
timeout and completion is extremely unlikely. Nevertheless this patch
fixes an issue with it.

Commit ad73d6feadbd7b ("mmc: complete requests from ->timeout")
preserved the existing functionality, to complete the request.
However that had only been necessary because the block layer
timeout handler had been marking the request to prevent it from being
completed normally. That restriction was removed at the same time, the
result being that a request that has gone will have been completed anyway.
That is, the completion was unnecessary.

At the time, the unnecessary completion was harmless because the block
layer would ignore it, although that changed in kernel v5.0.

Note for stable, this patch will not apply cleanly without patch "mmc:
core: Fix recursive locking issue in CQE recovery path"

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Fixes: ad73d6feadbd7b ("mmc: complete requests from ->timeout")
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200508062227.23144-1-adrian.hunter@intel.com
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

mmc: core: Check request type before completing the request

[ Upstream commit e6bfb1bf00852b55f4c771f47ae67004c04d3c87 ]

In the request completion path with CQE, request type is being checked
after the request is getting completed. This is resulting in returning
the wrong request type and leading to the IO hang issue.

ASYNC request type is getting returned for DCMD type requests.
Because of this mismatch, mq->cqe_busy flag is never getting cleared
and the driver is not invoking blk_mq_hw_run_queue. So requests are not
getting dispatched to the LLD from the block layer.

All these eventually leading to IO hang issues.
So, get the request type before completing the request.

Cc: <stable@vger.kernel.org>
Fixes: 1e8e55b67030 ("mmc: block: Add CQE support")
Signed-off-by: Veerabhadrarao Badiganti <vbadigan@codeaurora.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/1588775643-18037-2-git-send-email-vbadigan@codeaurora.org
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

i40iw: Fix error handling in i40iw_manage_arp_cache()

[ Upstream commit 37e31d2d26a4124506c24e95434e9baf3405a23a ]

The i40iw_arp_table() function can return -EOVERFLOW if
i40iw_alloc_resource() fails so we can't just test for "== -1".

Fixes: 4e9042e647ff ("i40iw: add hw and utils files")
Link: https://lore.kernel.org/r/20200422092211.GA195357@mwanda
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Shiraz Saleem <shiraz.saleem@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

pinctrl: cherryview: Add missing spinlock usage in chv_gpio_irq_handler

[ Upstream commit 69388e15f5078c961b9e5319e22baea4c57deff1 ]

According to Braswell NDA Specification Update (#557593),
concurrent read accesses may result in returning 0xffffffff and write
instructions may be dropped. We have an established format for the
commit references, i.e.
cdca06e4e859 ("pinctrl: baytrail: Add missing spinlock usage in
byt_gpio_irq_handler")

Fixes: 0bd50d719b00 ("pinctrl: cherryview: prevent concurrent access to GPIO controllers")
Signed-off-by: Grace Kao <grace.kao@intel.com>
Reported-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

pinctrl: baytrail: Enable pin configuration setting for GPIO chip

[ Upstream commit ccd025eaddaeb99e982029446197c544252108e2 ]

It appears that pin configuration for GPIO chip hasn't been enabled yet
due to absence of ->set_config() callback.

Enable it here for Intel Baytrail.

Fixes: c501d0b149de ("pinctrl: baytrail: Add pin control operations")
Depends-on: 2956b5d94a76 ("pinctrl / gpio: Introduce .set_config() callback for GPIO chips")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

gfs2: Another gfs2_walk_metadata fix

[ Upstream commit 566a2ab3c9005f62e784bd39022d58d34ef4365c ]

Make sure we don't walk past the end of the metadata in gfs2_walk_metadata: the
inode holds fewer pointers than indirect blocks.

Slightly clean up gfs2_iomap_get.

Fixes: a27a0c9b6a20 ("gfs2: gfs2_walk_metadata fix")
Cc: stable@vger.kernel.org # v5.3+
Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Signed-off-by: Bob Peterson <rpeterso@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

ALSA: hda/realtek - Fix S3 pop noise on Dell Wyse

[ Upstream commit 52e4e36807aeac1cdd07b14e509c8a64101e1a09 ]

Commit 317d9313925c ("ALSA: hda/realtek - Set default power save node to
0") makes the ALC225 have pop noise on S3 resume and cold boot.

The previous fix enable power save node universally for ALC225, however
it makes some ALC225 systems unable to produce any sound.

So let's only enable power save node for the affected Dell Wyse
platform.

Fixes: 317d9313925c ("ALSA: hda/realtek - Set default power save node to 0")
BugLink: https://bugs.launchpad.net/bugs/1866357
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
Link: https://lore.kernel.org/r/20200503152449.22761-2-kai.heng.feng@canonical.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

ipc/util.c: sysvipc_find_ipc() incorrectly updates position index

[ Upstream commit 5e698222c70257d13ae0816720dde57c56f81e15 ]

Commit 89163f93c6f9 ("ipc/util.c: sysvipc_find_ipc() should increase
position index") is causing this bug (seen on 5.6.8):

   # ipcs -q

   ------ Message Queues --------
   key        msqid      owner      perms      used-bytes   messages

   # ipcmk -Q
   Message queue id: 0
   # ipcs -q

   ------ Message Queues --------
   key        msqid      owner      perms      used-bytes   messages
   0x82db8127 0          root       644        0            0

   # ipcmk -Q
   Message queue id: 1
   # ipcs -q

   ------ Message Queues --------
   key        msqid      owner      perms      used-bytes   messages
   0x82db8127 0          root       644        0            0
   0x76d1fb2a 1          root       644        0            0

   # ipcrm -q 0
   # ipcs -q

   ------ Message Queues --------
   key        msqid      owner      perms      used-bytes   messages
   0x76d1fb2a 1          root       644        0            0
   0x76d1fb2a 1          root       644        0            0

   # ipcmk -Q
   Message queue id: 2
   # ipcrm -q 2
   # ipcs -q

   ------ Message Queues --------
   key        msqid      owner      perms      used-bytes   messages
   0x76d1fb2a 1          root       644        0            0
   0x76d1fb2a 1          root       644        0            0

   # ipcmk -Q
   Message queue id: 3
   # ipcrm -q 1
   # ipcs -q

   ------ Message Queues --------
   key        msqid      owner      perms      used-bytes   messages
   0x7c982867 3          root       644        0            0
   0x7c982867 3          root       644        0            0
   0x7c982867 3          root       644        0            0
   0x7c982867 3          root       644        0            0

Whenever an IPC item with a low id is deleted, the items with higher ids
are duplicated, as if filling a hole.

new_pos should jump through hole of unused ids, pos can be updated
inside "for" cycle.

Fixes: 89163f93c6f9 ("ipc/util.c: sysvipc_find_ipc() should increase position index")
Reported-by: Andreas Schwab <schwab@suse.de>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Waiman Long <longman@redhat.com>
Cc: NeilBrown <neilb@suse.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Oberparleiter <oberpar@linux.ibm.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/4921fe9b-9385-a2b4-1dc4-1099be6d2e39@virtuozzo.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drm/qxl: lost qxl_bo_kunmap_atomic_page in qxl_image_init_helper()

[ Upstream commit 5b5703dbafae74adfbe298a56a81694172caf5e6 ]

v2: removed TODO reminder

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Link: http://patchwork.freedesktop.org/patch/msgid/a4e0ae09-a73c-1c62-04ef-3f990d41bea9@virtuozzo.com
Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

ALSA: hda/hdmi: fix race in monitor detection during probe

[ Upstream commit ca76282b6faffc83601c25bd2a95f635c03503ef ]

A race exists between build_pcms() and build_controls() phases of codec
setup. Build_pcms() sets up notifier for jack events. If a monitor event
is received before build_controls() is run, the initial jack state is
lost and never reported via mixer controls.

The problem can be hit at least with SOF as the controller driver. SOF
calls snd_hda_codec_build_controls() in its workqueue-based probe and
this can be delayed enough to hit the race condition.

Fix the issue by invalidating the per-pin ELD information when
build_controls() is called. The existing call to hdmi_present_sense()
will update the ELD contents. This ensures initial monitor state is
correctly reflected via mixer controls.

BugLink: https://github.com/thesofproject/linux/issues/1687
Signed-off-by: Kai Vehmanen <kai.vehmanen@linux.intel.com>
Link: https://lore.kernel.org/r/20200428123836.24512-1-kai.vehmanen@linux.intel.com
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>

cpufreq: intel_pstate: Only mention the BIOS disabling turbo mode once

[ Upstream commit 8c539776ac83c0857395e1ccc9c6b516521a2d32 ]

Make a note of the first time we discover the turbo mode has been
disabled by the BIOS, as otherwise we complain every time we try to
update the mode.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

dmaengine: mmp_tdma: Reset channel error on release

[ Upstream commit 0c89446379218698189a47871336cb30286a7197 ]

When a channel configuration fails, the status of the channel is set to
DEV_ERROR so that an attempt to submit it fails. However, this status
sticks until the heat end of the universe, making it impossible to
recover from the error.

Let's reset it when the channel is released so that further use of the
channel with correct configuration is not impacted.

Signed-off-by: Lubomir Rintel <lkundrak@v3.sk>
Link: https://lore.kernel.org/r/20200419164912.670973-5-lkundrak@v3.sk
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

dmaengine: pch_dma.c: Avoid data race between probe and irq handler

[ Upstream commit 2e45676a4d33af47259fa186ea039122ce263ba9 ]

pd->dma.dev is read in irq handler pd_irq().
However, it is set to pdev->dev after request_irq().
Therefore, set pd->dma.dev to pdev->dev before request_irq() to
avoid data race between pch_dma_probe() and pd_irq().

Found by Linux Driver Verification project (linuxtesting.org).

Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Link: https://lore.kernel.org/r/20200416062335.29223-1-madhuparnabhowmik10@gmail.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

riscv: fix vdso build with lld

[ Upstream commit 3c1918c8f54166598195d938564072664a8275b1 ]

When building with the LLVM linker this error occurrs:
    LD      arch/riscv/kernel/vdso/vdso-syms.o
  ld.lld: error: no input files

This happens because the lld treats -R as an alias to -rpath, as opposed
to ld where -R means --just-symbols.

Use the long option name for compatibility between the two.

Link: https://github.com/ClangBuiltLinux/linux/issues/805
Reported-by: Dmitry Golovin <dima@golovin.in>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Ilie Halip <ilie.halip@gmail.com>
Reviewed-by: Fangrui Song <maskray@google.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

tcp: fix SO_RCVLOWAT hangs with fat skbs

[ Upstream commit 24adbc1676af4e134e709ddc7f34cf2adc2131e4 ]

We autotune rcvbuf whenever SO_RCVLOWAT is set to account for 100%
overhead in tcp_set_rcvlowat()

This works well when skb->len/skb->truesize ratio is bigger than 0.5

But if we receive packets with small MSS, we can end up in a situation
where not enough bytes are available in the receive queue to satisfy
RCVLOWAT setting.
As our sk_rcvbuf limit is hit, we send zero windows in ACK packets,
preventing remote peer from sending more data.

Even autotuning does not help, because it only triggers at the time
user process drains the queue. If no EPOLLIN is generated, this
can not happen.

Note poll() has a similar issue, after commit
c7004482e8dc ("tcp: Respect SO_RCVLOWAT in tcp_poll().")

Fixes: 03f45c883c6f ("tcp: avoid extra wakeups for SO_RCVLOWAT users")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: tcp: fix rx timestamp behavior for tcp_recvmsg

[ Upstream commit cc4de047b33be247f9c8150d3e496743a49642b8 ]

The stated intent of the original commit is to is to "return the timestamp
corresponding to the highest sequence number data returned." The current
implementation returns the timestamp for the last byte of the last fully
read skb, which is not necessarily the last byte in the recv buffer. This
patch converts behavior to the original definition, and to the behavior of
the previous draft versions of commit 98aaa913b4ed ("tcp: Extend
SOF_TIMESTAMPING_RX_SOFTWARE to TCP recvmsg") which also match this
behavior.

Fixes: 98aaa913b4ed ("tcp: Extend SOF_TIMESTAMPING_RX_SOFTWARE to TCP recvmsg")
Co-developed-by: Iris Liu <iris@onechronos.com>
Signed-off-by: Iris Liu <iris@onechronos.com>
Signed-off-by: Kelly Littlepage <kelly@onechronos.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

netprio_cgroup: Fix unlimited memory leak of v2 cgroups

[ Upstream commit 090e28b229af92dc5b40786ca673999d59e73056 ]

If systemd is configured to use hybrid mode which enables the use of
both cgroup v1 and v2, systemd will create new cgroup on both the default
root (v2) and netprio_cgroup hierarchy (v1) for a new session and attach
task to the two cgroups. If the task does some network thing then the v2
cgroup can never be freed after the session exited.

One of our machines ran into OOM due to this memory leak.

In the scenario described above when sk_alloc() is called
cgroup_sk_alloc() thought it's in v2 mode, so it stores
the cgroup pointer in sk->sk_cgrp_data and increments
the cgroup refcnt, but then sock_update_netprioidx()
thought it's in v1 mode, so it stores netprioidx value
in sk->sk_cgrp_data, so the cgroup refcnt will never be freed.

Currently we do the mode switch when someone writes to the ifpriomap
cgroup control file. The easiest fix is to also do the switch when
a task is attached to a new cgroup.

Fixes: bd1060a1d671 ("sock, cgroup: add sock->sk_cgroup")
Reported-by: Yang Yingliang <yangyingliang@huawei.com>
Tested-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Zefan Li <lizefan@huawei.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: ipv4: really enforce backoff for redirects

[ Upstream commit 57644431a6c2faac5d754ebd35780cf43a531b1a ]

In commit b406472b5ad7 ("net: ipv4: avoid mixed n_redirects and
rate_tokens usage") I missed the fact that a 0 'rate_tokens' will
bypass the backoff algorithm.

Since rate_tokens is cleared after a redirect silence, and never
incremented on redirects, if the host keeps receiving packets
requiring redirect it will reply ignoring the backoff.

Additionally, the 'rate_last' field will be updated with the
cadence of the ingress packet requiring redirect. If that rate is
high enough, that will prevent the host from generating any
other kind of ICMP messages

The check for a zero 'rate_tokens' value was likely a shortcut
to avoid the more complex backoff algorithm after a redirect
silence period. Address the issue checking for 'n_redirects'
instead, which is incremented on successful redirect, and
does not interfere with other ICMP replies.

Fixes: b406472b5ad7 ("net: ipv4: avoid mixed n_redirects and rate_tokens usage")
Reported-and-tested-by: Colin Walters <walters@redhat.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: dsa: loop: Add module soft dependency

[ Upstream commit 3047211ca11bf77b3ecbce045c0aa544d934b945 ]

There is a soft dependency against dsa_loop_bdinfo.ko which sets up the
MDIO device registration, since there are no symbols referenced by
dsa_loop.ko, there is no automatic loading of dsa_loop_bdinfo.ko which
is needed.

Fixes: 98cd1552ea27 ("net: dsa: Mock-up driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

hinic: fix a bug of ndo_stop

[ Upstream commit e8a1b0efd632d1c9db7d4e93da66377c7b524862 ]

if some function in ndo_stop interface returns failure because of
hardware fault, must go on excuting rest steps rather than return
failure directly, otherwise will cause memory leak.And bump the
timeout for SET_FUNC_STATE to ensure that cmd won't return failure
when hw is busy. Otherwise hw may stomp host memory if we free
memory regardless of the return value of SET_FUNC_STATE.

Fixes: 51ba902a16e6 ("net-next/hinic: Initialize hw interface")
Signed-off-by: Luo bin <luobin9@huawei.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

virtio_net: fix lockdep warning on 32 bit

[ Upstream commit 01c3259818a11f3cc3cd767adbae6b45849c03c1 ]

When we fill up a receive VQ, try_fill_recv currently tries to count
kicks using a 64 bit stats counter. Turns out, on a 32 bit kernel that
uses a seqcount. sequence counts are "lock" constructs where you need to
make sure that writers are serialized.

In turn, this means that we mustn't run two try_fill_recv concurrently.
Which of course we don't. We do run try_fill_recv sometimes from a
softirq napi context, and sometimes from a fully preemptible context,
but the later always runs with napi disabled.

However, when it comes to the seqcount, lockdep is trying to enforce the
rule that the same lock isn't accessed from preemptible and softirq
context - it doesn't know about napi being enabled/disabled. This causes
a false-positive warning:

WARNING: inconsistent lock state
...
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.

As a work around, shut down the warning by switching
to u64_stats_update_begin_irqsave - that works by disabling
interrupts on 32 bit only, is a NOP on 64 bit.

Reported-by: Thomas Gleixner <tglx@linutronix.de>
Suggested-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

tcp: fix error recovery in tcp_zerocopy_receive()

[ Upstream commit e776af608f692a7a647455106295fa34469e7475 ]

If user provides wrong virtual address in TCP_ZEROCOPY_RECEIVE
operation we want to return -EINVAL error.

But depending on zc->recv_skip_hint content, we might return
-EIO error if the socket has SOCK_DONE set.

Make sure to return -EINVAL in this case.

BUG: KMSAN: uninit-value in tcp_zerocopy_receive net/ipv4/tcp.c:1833 [inline]
BUG: KMSAN: uninit-value in do_tcp_getsockopt+0x4494/0x6320 net/ipv4/tcp.c:3685
CPU: 1 PID: 625 Comm: syz-executor.0 Not tainted 5.7.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x1c9/0x220 lib/dump_stack.c:118
 kmsan_report+0xf7/0x1e0 mm/kmsan/kmsan_report.c:121
 __msan_warning+0x58/0xa0 mm/kmsan/kmsan_instr.c:215
 tcp_zerocopy_receive net/ipv4/tcp.c:1833 [inline]
 do_tcp_getsockopt+0x4494/0x6320 net/ipv4/tcp.c:3685
 tcp_getsockopt+0xf8/0x1f0 net/ipv4/tcp.c:3728
 sock_common_getsockopt+0x13f/0x180 net/core/sock.c:3131
 __sys_getsockopt+0x533/0x7b0 net/socket.c:2177
 __do_sys_getsockopt net/socket.c:2192 [inline]
 __se_sys_getsockopt+0xe1/0x100 net/socket.c:2189
 __x64_sys_getsockopt+0x62/0x80 net/socket.c:2189
 do_syscall_64+0xb8/0x160 arch/x86/entry/common.c:297
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45c829
Code: 0d b7 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 0f 83 db b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f1deeb72c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00000000004e01e0 RCX: 000000000045c829
RDX: 0000000000000023 RSI: 0000000000000006 RDI: 0000000000000009
RBP: 000000000078bf00 R08: 0000000020000200 R09: 0000000000000000
R10: 00000000200001c0 R11: 0000000000000246 R12: 00000000ffffffff
R13: 00000000000001d8 R14: 00000000004d3038 R15: 00007f1deeb736d4

Local variable ----zc@do_tcp_getsockopt created at:
 do_tcp_getsockopt+0x1a74/0x6320 net/ipv4/tcp.c:3670
 do_tcp_getsockopt+0x1a74/0x6320 net/ipv4/tcp.c:3670

Fixes: 05255b823a61 ("tcp: add TCP_ZEROCOPY_RECEIVE support for zerocopy receive")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Revert "ipv6: add mtu lock check in __ip6_rt_update_pmtu"

[ Upstream commit 09454fd0a4ce23cb3d8af65066c91a1bf27120dd ]

This reverts commit 19bda36c4299ce3d7e5bce10bebe01764a655a6d:

| ipv6: add mtu lock check in __ip6_rt_update_pmtu
|
| Prior to this patch, ipv6 didn't do mtu lock check in ip6_update_pmtu.
| It leaded to that mtu lock doesn't really work when receiving the pkt
| of ICMPV6_PKT_TOOBIG.
|
| This patch is to add mtu lock check in __ip6_rt_update_pmtu just as ipv4
| did in __ip_rt_update_pmtu.

The above reasoning is incorrect.  IPv6 *requires* icmp based pmtu to work.
There's already a comment to this effect elsewhere in the kernel:

  $ git grep -p -B1 -A3 'RTAX_MTU lock'
  net/ipv6/route.c=4813=

  static int rt6_mtu_change_route(struct fib6_info *f6i, void *p_arg)
  ...
    /* In IPv6 pmtu discovery is not optional,
       so that RTAX_MTU lock cannot disable it.
       We still use this lock to block changes
       caused by addrconf/ndisc.
    */

This reverts to the pre-4.9 behaviour.

Cc: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Cc: Xin Long <lucien.xin@gmail.com>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Fixes: 19bda36c4299 ("ipv6: add mtu lock check in __ip6_rt_update_pmtu")
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

pppoe: only process PADT targeted at local interfaces

[ Upstream commit b8c158395119be62294da73646a3953c29ac974b ]

We don't want to disconnect a session because of a stray PADT arriving
while the interface is in promiscuous mode.
Furthermore, multicast and broadcast packets make no sense here, so
only PACKET_HOST is accepted.

Reported-by: David Balažic <xerces9@gmail.com>
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: phy: fix aneg restart in phy_ethtool_set_eee

[ Upstream commit 9de5d235b60a7cdfcdd5461e70c5663e713fde87 ]

phy_restart_aneg() enables aneg in the PHY. That's not what we want
if phydev->autoneg is disabled. In this case still update EEE
advertisement register, but don't enable aneg and don't trigger an
aneg restart.

Fixes: f75abeb8338e ("net: phy: restart phy autonegotiation after EEE advertisment change")
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

netlabel: cope with NULL catmap

[ Upstream commit eead1c2ea2509fd754c6da893a94f0e69e83ebe4 ]

The cipso and calipso code can set the MLS_CAT attribute on
successful parsing, even if the corresponding catmap has
not been allocated, as per current configuration and external
input.

Later, selinux code tries to access the catmap if the MLS_CAT flag
is present via netlbl_catmap_getlong(). That may cause null ptr
dereference while processing incoming network traffic.

Address the issue setting the MLS_CAT flag only if the catmap is
really allocated. Additionally let netlbl_catmap_getlong() cope
with NULL catmap.

Reported-by: Matthew Sheets <matthew.sheets@gd-ms.com>
Fixes: 4b8feff251da ("netlabel: fix the horribly broken catmap functions")
Fixes: ceba1832b1b2 ("calipso: Set the calipso socket label to match the secattr.")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net: fix a potential recursive NETDEV_FEAT_CHANGE

[ Upstream commit dd912306ff008891c82cd9f63e8181e47a9cb2fb ]

syzbot managed to trigger a recursive NETDEV_FEAT_CHANGE event
between bonding master and slave. I managed to find a reproducer
for this:

  ip li set bond0 up
  ifenslave bond0 eth0
  brctl addbr br0
  ethtool -K eth0 lro off
  brctl addif br0 bond0
  ip li set br0 up

When a NETDEV_FEAT_CHANGE event is triggered on a bonding slave,
it captures this and calls bond_compute_features() to fixup its
master's and other slaves' features. However, when syncing with
its lower devices by netdev_sync_lower_features() this event is
triggered again on slaves when the LRO feature fails to change,
so it goes back and forth recursively until the kernel stack is
exhausted.

Commit 17b85d29e82c intentionally lets __netdev_update_features()
return -1 for such a failure case, so we have to just rely on
the existing check inside netdev_sync_lower_features() and skip
NETDEV_FEAT_CHANGE event only for this specific failure case.

Fixes: fd867d51f889 ("net/core: generic support for disabling netdev features down stack")
Reported-by: syzbot+e73ceacfd8560cc8a3ca@syzkaller.appspotmail.com
Reported-by: syzbot+c2fb6f9ddcea95ba49b5@syzkaller.appspotmail.com
Cc: Jarod Wilson <jarod@redhat.com>
Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jann Horn <jannh@google.com>
Reviewed-by: Jay Vosburgh <jay.vosburgh@canonical.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

mmc: sdhci-acpi: Add SDHCI_QUIRK2_BROKEN_64_BIT_DMA for AMDI0040

[ Upstream commit 45a3fe3bf93b7cfeddc28ef7386555e05dc57f06 ]

The AMD eMMC 5.0 controller does not support 64 bit DMA.

Fixes: 34597a3f60b1 ("mmc: sdhci-acpi: Add support for ACPI HID of AMD Controller with HS400")
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Link: https://marc.info/?l=linux-mmc&m=158879884514552&w=2
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Link: https://lore.kernel.org/r/20200508165344.1.Id5bb8b1ae7ea576f26f9d91c761df7ccffbf58c5@changeid
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

scsi: sg: add sg_remove_request in sg_write

commit 83c6f2390040f188cc25b270b4befeb5628c1aee upstream.

If the __copy_from_user function failed we need to call sg_remove_request
in sg_write.

Link: https://lore.kernel.org/r/610618d9-e983-fd56-ed0f-639428343af7@huawei.com
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Wu Bo <wubo40@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
[groeck: Backport to v5.4.y and older kernels]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

virtio-blk: handle block_device_operations callbacks after hot unplug

[ Upstream commit 90b5feb8c4bebc76c27fcaf3e1a0e5ca2d319e9e ]

A userspace process holding a file descriptor to a virtio_blk device can
still invoke block_device_operations after hot unplug.  This leads to a
use-after-free accessing vblk->vdev in virtblk_getgeo() when
ioctl(HDIO_GETGEO) is invoked:

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000090
  IP: [<ffffffffc00e5450>] virtio_check_driver_offered_feature+0x10/0x90 [virtio]
  PGD 800000003a92f067 PUD 3a930067 PMD 0
  Oops: 0000 [#1] SMP
  CPU: 0 PID: 1310 Comm: hdio-getgeo Tainted: G           OE  ------------   3.10.0-1062.el7.x86_64 #1
  Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
  task: ffff9be5fbfb8000 ti: ffff9be5fa890000 task.ti: ffff9be5fa890000
  RIP: 0010:[<ffffffffc00e5450>]  [<ffffffffc00e5450>] virtio_check_driver_offered_feature+0x10/0x90 [virtio]
  RSP: 0018:ffff9be5fa893dc8  EFLAGS: 00010246
  RAX: ffff9be5fc3f3400 RBX: ffff9be5fa893e30 RCX: 0000000000000000
  RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff9be5fbc10b40
  RBP: ffff9be5fa893dc8 R08: 0000000000000301 R09: 0000000000000301
  R10: 0000000000000000 R11: 0000000000000000 R12: ffff9be5fdc24680
  R13: ffff9be5fbc10b40 R14: ffff9be5fbc10480 R15: 0000000000000000
  FS:  00007f1bfb968740(0000) GS:ffff9be5ffc00000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000090 CR3: 000000003a894000 CR4: 0000000000360ff0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  Call Trace:
   [<ffffffffc016ac37>] virtblk_getgeo+0x47/0x110 [virtio_blk]
   [<ffffffff8d3f200d>] ? handle_mm_fault+0x39d/0x9b0
   [<ffffffff8d561265>] blkdev_ioctl+0x1f5/0xa20
   [<ffffffff8d488771>] block_ioctl+0x41/0x50
   [<ffffffff8d45d9e0>] do_vfs_ioctl+0x3a0/0x5a0
   [<ffffffff8d45dc81>] SyS_ioctl+0xa1/0xc0

A related problem is that virtblk_remove() leaks the vd_index_ida index
when something still holds a reference to vblk->disk during hot unplug.
This causes virtio-blk device names to be lost (vda, vdb, etc).

Fix these issues by protecting vblk->vdev with a mutex and reference
counting vblk so the vd_index_ida index can be removed in all cases.

Fixes: 48e4043d4529 ("virtio: add virtio disk geometry feature")
Reported-by: Lance Digby <ldigby@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Link: https://lore.kernel.org/r/20200430140442.171016-1-stefanha@redhat.com
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Stefano Garzarella <sgarzare@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

drop_monitor: work around gcc-10 stringop-overflow warning

[ Upstream commit dc30b4059f6e2abf3712ab537c8718562b21c45d ]

The current gcc-10 snapshot produces a false-positive warning:

net/core/drop_monitor.c: In function 'trace_drop_common.constprop':
cc1: error: writing 8 bytes into a region of size 0 [-Werror=stringop-overflow=]
In file included from net/core/drop_monitor.c:23:
include/uapi/linux/net_dropmon.h:36:8: note: at offset 0 to object 'entries' with size 4 declared here
   36 |  __u32 entries;
      |        ^~~~~~~

I reported this in the gcc bugzilla, but in case it does not get
fixed in the release, work around it by using a temporary variable.

Fixes: 9a8afc8d3962 ("Network Drop Monitor: Adding drop monitor implementation & Netlink protocol")
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94881
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

net: moxa: Fix a potential double 'free_irq()'

[ Upstream commit ee8d2267f0e39a1bfd95532da3a6405004114b27 ]

Should an irq requested with 'devm_request_irq' be released explicitly,
it should be done by 'devm_free_irq()', not 'free_irq()'.

Fixes: 6c821bd9edc9 ("net: Add MOXA ART SoCs ethernet driver")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

net/sonic: Fix a resource leak in an error handling path in 'jazz_sonic_probe()'

[ Upstream commit 10e3cc180e64385edc9890c6855acf5ed9ca1339 ]

A call to 'dma_alloc_coherent()' is hidden in 'sonic_alloc_descriptors()',
called from 'sonic_probe1()'.

This is correctly freed in the remove function, but not in the error
handling path of the probe function.
Fix it and add the missing 'dma_free_coherent()' call.

While at it, rename a label in order to be slightly more informative.

Fixes: efcce839360f ("[PATCH] macsonic/jazzsonic network drivers update")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>

shmem: fix possible deadlocks on shmlock_user_lock

[ Upstream commit ea0dfeb4209b4eab954d6e00ed136bc6b48b380d ]

Recent commit 71725ed10c40 ("mm: huge tmpfs: try to split_huge_page()
when punching hole") has allowed syzkaller to probe deeper, uncovering a
long-standing lockdep issue between the irq-unsafe shmlock_user_lock,
the irq-safe xa_lock on mapping->i_pages, and shmem inode's info->lock
which nests inside xa_lock (or tree_lock) since 4.8's shmem_uncharge().

user_shm_lock(), servicing SysV shmctl(SHM_LOCK), wants
shmlock_user_lock while its caller shmem_lock() holds info->lock with
interrupts disabled; but hugetlbfs_file_setup() calls user_shm_lock()
with interrupts enabled, and might be interrupted by a writeback endio
wanting xa_lock on i_pages.

This may not risk an actual deadlock, since shmem inodes do not take
part in writeback accounting, but there are several easy ways to avoid
it.

Requiring interrupts disabled for shmlock_user_lock would be easy, but
it's a high-level global lock for which that seems inappropriate.
Instead, recall that the use of info->lock to guard info->flags in
shmem_lock() dates from pre-3.1 days, when races with SHMEM_PAGEIN and
SHMEM_TRUNCATE could occur: nowadays it serves no purpose, the only flag
added or removed is VM_LOCKED itself, and calls to shmem_lock() an inode
are already serialized by the caller.

Take info->lock out of the chain and the possibility of deadlock or
lockdep warning goes away.

Fixes: 4595ef88d136 ("shmem: make shmem_inode_info::lock irq-safe")
Reported-by: syzbot+c8a8197c8852f566b9d9@syzkaller.appspotmail.com
Reported-by: syzbot+40b71e145e73f78f81ad@syzkaller.appspotmail.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2004161707410.16322@eggly.anvils
Link: https://lore.kernel.org/lkml/000000000000e5838c05a3152f53@google.com/
Link: https://lore.kernel.org/lkml/0000000000003712b305a331d3b1@google.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

net: dsa: Do not make user port errors fatal

commit 86f8b1c01a0a537a73d2996615133be63cdf75db upstream.

Prior to 1d27732f411d ("net: dsa: setup and teardown ports"), we would
not treat failures to set-up an user port as fatal, but after this
commit we would, which is a regression for some systems where interfaces
may be declared in the Device Tree, but the underlying hardware may not
be present (pluggable daughter cards for instance).

Fixes: 1d27732f411d ("net: dsa: setup and teardown ports")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Reviewed-by: Andrew Lunn <andrew@lunn.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Linux 4.19.123

ipc/mqueue.c: change __do_notify() to bypass check_kill_permission()

[ Upstream commit b5f2006144c6ae941726037120fa1001ddede784 ]

Commit cc731525f26a ("signal: Remove kernel interal si_code magic")
changed the value of SI_FROMUSER(SI_MESGQ), this means that mq_notify() no
longer works if the sender doesn't have rights to send a signal.

Change __do_notify() to use do_send_sig_info() instead of kill_pid_info()
to avoid check_kill_permission().

This needs the additional notify.sigev_signo != 0 check, shouldn't we
change do_mq_notify() to deny sigev_signo == 0 ?

Test-case:

#include <signal.h>
#include <mqueue.h>
#include <unistd.h>
#include <sys/wait.h>
#include <assert.h>

static int notified;

static void sigh(int sig)
{
notified = 1;
}

int main(void)
{
signal(SIGIO, sigh);

int fd = mq_open("/mq", O_RDWR|O_CREAT, 0666, NULL);
assert(fd >= 0);

struct sigevent se = {
.sigev_notify = SIGEV_SIGNAL,
.sigev_signo = SIGIO,
};
assert(mq_notify(fd, &se) == 0);

if (!fork()) {
assert(setuid(1) == 0);
mq_send(fd, "",1,0);
return 0;
}

wait(NULL);
mq_unlink("/mq");
assert(notified);
return 0;
}

[manfred@colorfullife.com: 1) Add self_exec_id evaluation so that the implementation matches do_notify_parent 2) use PIDTYPE_TGID everywhere]
Fixes: cc731525f26a ("signal: Remove kernel interal si_code magic")
Reported-by: Yoji <yoji.fujihar.min@gmail.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Markus Elfring <elfring@users.sourceforge.net>
Cc: <1vier1@web.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/e2a782e4-eab9-4f5c-c749-c07a8f7a4e66@colorfullife.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

scripts/decodecode: fix trapping instruction formatting

commit e08df079b23e2e982df15aa340bfbaf50f297504 upstream.

If the trapping instruction contains a ':', for a memory access through
segment registers for example, the sed substitution will insert the '*'
marker in the middle of the instruction instead of the line address:

2b:   65 48 0f c7 0f          cmpxchg16b %gs:*(%rdi)          <-- trapping instruction

I started to think I had forgotten some quirk of the assembly syntax
before noticing that it was actually coming from the script.  Fix it to
add the address marker at the right place for these instructions:

28:   49 8b 06                mov    (%r14),%rax
2b:*  65 48 0f c7 0f          cmpxchg16b %gs:(%rdi)           <-- trapping instruction
30:   0f 94 c0                sete   %al

Fixes: 18ff44b189e2 ("scripts/decodecode: make faulting insn ptr more robust")
Signed-off-by: Ivan Delalande <colona@arista.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20200419223653.GA31248@visor
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

objtool: Fix stack offset tracking for indirect CFAs

commit d8dd25a461e4eec7190cb9d66616aceacc5110ad upstream.

When the current frame address (CFA) is stored on the stack (i.e.,
cfa->base == CFI_SP_INDIRECT), objtool neglects to adjust the stack
offset when there are subsequent pushes or pops.  This results in bad
ORC data at the end of the ENTER_IRQ_STACK macro, when it puts the
previous stack pointer on the stack and does a subsequent push.

This fixes the following unwinder warning:

  WARNING: can't dereference registers at 00000000f0a6bdba for ip interrupt_entry+0x9f/0xa0

Fixes: 627fce14809b ("objtool: Add ORC unwind table generation")
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Reported-by: Dave Jones <dsj@fb.com>
Reported-by: Steven Rostedt <rostedt@goodmis.org>
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Reported-by: Joe Mario <jmario@redhat.com>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Jann Horn <jannh@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/853d5d691b29e250333332f09b8e27410b2d9924.1587808742.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

netfilter: nf_osf: avoid passing pointer to local var

commit c165d57b552aaca607fa5daf3fb524a6efe3c5a3 upstream.

gcc-10 points out that a code path exists where a pointer to a stack
variable may be passed back to the caller:

net/netfilter/nfnetlink_osf.c: In function 'nf_osf_hdr_ctx_init':
cc1: warning: function may return address of local variable [-Wreturn-local-addr]
net/netfilter/nfnetlink_osf.c:171:16: note: declared here
  171 |  struct tcphdr _tcph;
      |                ^~~~~

I am not sure whether this can happen in practice, but moving the
variable declaration into the callers avoids the problem.

Fixes: 31a9c29210e2 ("netfilter: nf_osf: add struct nf_osf_hdr_ctx")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

netfilter: nat: never update the UDP checksum when it's 0

commit ea64d8d6c675c0bb712689b13810301de9d8f77a upstream.

If the UDP header of a local VXLAN endpoint is NAT-ed, and the VXLAN
device has disabled UDP checksums and enabled Tx checksum offloading,
then the skb passed to udp_manip_pkt() has hdr->check == 0 (outer
checksum disabled) and skb->ip_summed == CHECKSUM_PARTIAL (inner packet
checksum offloaded).

Because of the ->ip_summed value, udp_manip_pkt() tries to update the
outer checksum with the new address and port, leading to an invalid
checksum sent on the wire, as the original null checksum obviously
didn't take the old address and port into account.

So, we can't take ->ip_summed into account in udp_manip_pkt(), as it
might not refer to the checksum we're acting on. Instead, we can base
the decision to update the UDP checksum entirely on the value of
hdr->check, because it's null if and only if checksum is disabled:

  * A fully computed checksum can't be 0, since a 0 checksum is
    represented by the CSUM_MANGLED_0 value instead.

  * A partial checksum can't be 0, since the pseudo-header always adds
    at least one non-zero value (the UDP protocol type 0x11) and adding
    more values to the sum can't make it wrap to 0 as the carry is then
    added to the wrapped number.

  * A disabled checksum uses the special value 0.

The problem seems to be there from day one, although it was probably
not visible before UDP tunnels were implemented.

Fixes: 5b1158e909ec ("[NETFILTER]: Add NAT support for nf_conntrack")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/unwind/orc: Fix premature unwind stoppage due to IRET frames

commit 81b67439d147677d844d492fcbd03712ea438f42 upstream.

The following execution path is possible:

  fsnotify()
    [ realign the stack and store previous SP in R10 ]
    <IRQ>
      [ only IRET regs saved ]
      common_interrupt()
        interrupt_entry()
  <NMI>
    [ full pt_regs saved ]
    ...
    [ unwind stack ]

When the unwinder goes through the NMI and the IRQ on the stack, and
then sees fsnotify(), it doesn't have access to the value of R10,
because it only has the five IRET registers.  So the unwind stops
prematurely.

However, because the interrupt_entry() code is careful not to clobber
R10 before saving the full regs, the unwinder should be able to read R10
from the previously saved full pt_regs associated with the NMI.

Handle this case properly.  When encountering an IRET regs frame
immediately after a full pt_regs frame, use the pt_regs as a backup
which can be used to get the C register values.

Also, note that a call frame resets the 'prev_regs' value, because a
function is free to clobber the registers.  For this fix to work, the
IRET and full regs frames must be adjacent, with no FUNC frames in
between.  So replace the FUNC hint in interrupt_entry() with an
IRET_REGS hint.

Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder")
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Jones <dsj@fb.com>
Cc: Jann Horn <jannh@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lore.kernel.org/r/97a408167cc09f1cfa0de31a7b70dd88868d743f.1587808742.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/unwind/orc: Fix error path for bad ORC entry type

commit a0f81bf26888048100bf017fadf438a5bdffa8d8 upstream.

If the ORC entry type is unknown, nothing else can be done other than
reporting an error.  Exit the function instead of breaking out of the
switch statement.

Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder")
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Jones <dsj@fb.com>
Cc: Jann Horn <jannh@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lore.kernel.org/r/a7fa668ca6eabbe81ab18b2424f15adbbfdc810a.1587808742.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/unwind/orc: Prevent unwinding before ORC initialization

commit 98d0c8ebf77e0ba7c54a9ae05ea588f0e9e3f46e upstream.

If the unwinder is called before the ORC data has been initialized,
orc_find() returns NULL, and it tries to fall back to using frame
pointers.  This can cause some unexpected warnings during boot.

Move the 'orc_init' check from orc_find() to __unwind_init(), so that it
doesn't even try to unwind from an uninitialized state.

Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder")
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Jones <dsj@fb.com>
Cc: Jann Horn <jannh@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lore.kernel.org/r/069d1499ad606d85532eb32ce39b2441679667d5.1587808742.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/unwind/orc: Don't skip the first frame for inactive tasks

commit f1d9a2abff66aa8156fbc1493abed468db63ea48 upstream.

When unwinding an inactive task, the ORC unwinder skips the first frame
by default.  If both the 'regs' and 'first_frame' parameters of
unwind_start() are NULL, 'state->sp' and 'first_frame' are later
initialized to the same value for an inactive task.  Given there is a
"less than or equal to" comparison used at the end of __unwind_start()
for skipping stack frames, the first frame is skipped.

Drop the equal part of the comparison and make the behavior equivalent
to the frame pointer unwinder.

Fixes: ee9f8fce9964 ("x86/unwind: Add the ORC unwinder")
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Jones <dsj@fb.com>
Cc: Jann Horn <jannh@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lore.kernel.org/r/7f08db872ab59e807016910acdbe82f744de7065.1587808742.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/entry/64: Fix unwind hints in rewind_stack_do_exit()

commit f977df7b7ca45a4ac4b66d30a8931d0434c394b1 upstream.

The LEAQ instruction in rewind_stack_do_exit() moves the stack pointer
directly below the pt_regs at the top of the task stack before calling
do_exit(). Tell the unwinder to expect pt_regs.

Fixes: 8c1f75587a18 ("x86/entry/64: Add unwind hint annotations")
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Jones <dsj@fb.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lore.kernel.org/r/68c33e17ae5963854916a46f522624f8e1d264f2.1587808742.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/entry/64: Fix unwind hints in kernel exit path

commit 1fb143634a38095b641a3a21220774799772dc4c upstream.

In swapgs_restore_regs_and_return_to_usermode, after the stack is
switched to the trampoline stack, the existing UNWIND_HINT_REGS hint is
no longer valid, which can result in the following ORC unwinder warning:

  WARNING: can't dereference registers at 000000003aeb0cdd for ip swapgs_restore_regs_and_return_to_usermode+0x93/0xa0

For full correctness, we could try to add complicated unwind hints so
the unwinder could continue to find the registers, but when when it's
this close to kernel exit, unwind hints aren't really needed anymore and
it's fine to just use an empty hint which tells the unwinder to stop.

For consistency, also move the UNWIND_HINT_EMPTY in
entry_SYSCALL_64_after_hwframe to a similar location.

Fixes: 3e3b9293d392 ("x86/entry/64: Return to userspace from the trampoline stack")
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Reported-by: Dave Jones <dsj@fb.com>
Reported-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reported-by: Joe Mario <jmario@redhat.com>
Reported-by: Jann Horn <jannh@google.com>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/60ea8f562987ed2d9ace2977502fe481c0d7c9a0.1587808742.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/entry/64: Fix unwind hints in register clearing code

commit 06a9750edcffa808494d56da939085c35904e618 upstream.

The PUSH_AND_CLEAR_REGS macro zeroes each register immediately after
pushing it.  If an NMI or exception hits after a register is cleared,
but before the UNWIND_HINT_REGS annotation, the ORC unwinder will
wrongly think the previous value of the register was zero.  This can
confuse the unwinding process and cause it to exit early.

Because ORC is simpler than DWARF, there are a limited number of unwind
annotation states, so it's not possible to add an individual unwind hint
after each push/clear combination.  Instead, the register clearing
instructions need to be consolidated and moved to after the
UNWIND_HINT_REGS annotation.

Fixes: 3f01daecd545 ("x86/entry/64: Introduce the PUSH_AND_CLEAN_REGS macro")
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Dave Jones <dsj@fb.com>
Cc: Jann Horn <jannh@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lore.kernel.org/r/68fd3d0bc92ae2d62ff7879d15d3684217d51f08.1587808742.git.jpoimboe@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

batman-adv: Fix refcnt leak in batadv_v_ogm_process

commit 6f91a3f7af4186099dd10fa530dd7e0d9c29747d upstream.

batadv_v_ogm_process() invokes batadv_hardif_neigh_get(), which returns
a reference of the neighbor object to "hardif_neigh" with increased
refcount.

When batadv_v_ogm_process() returns, "hardif_neigh" becomes invalid, so
the refcount should be decreased to keep refcount balanced.

The reference counting issue happens in one exception handling paths of
batadv_v_ogm_process(). When batadv_v_ogm_orig_get() fails to get the
orig node and returns NULL, the refcnt increased by
batadv_hardif_neigh_get() is not decreased, causing a refcnt leak.

Fix this issue by jumping to "out" label when batadv_v_ogm_orig_get()
fails to get the orig node.

Fixes: 9323158ef9f4 ("batman-adv: OGMv2 - implement originators logic")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

batman-adv: Fix refcnt leak in batadv_store_throughput_override

commit 6107c5da0fca8b50b4d3215e94d619d38cc4a18c upstream.

batadv_show_throughput_override() invokes batadv_hardif_get_by_netdev(),
which gets a batadv_hard_iface object from net_dev with increased refcnt
and its reference is assigned to a local pointer 'hard_iface'.

When batadv_store_throughput_override() returns, "hard_iface" becomes
invalid, so the refcount should be decreased to keep refcount balanced.

The issue happens in one error path of
batadv_store_throughput_override(). When batadv_parse_throughput()
returns NULL, the refcnt increased by batadv_hardif_get_by_netdev() is
not decreased, causing a refcnt leak.

Fix this issue by jumping to "out" label when batadv_parse_throughput()
returns NULL.

Fixes: 0b5ecc6811bd ("batman-adv: add throughput override attribute to hard_ifaces")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

batman-adv: Fix refcnt leak in batadv_show_throughput_override

commit f872de8185acf1b48b954ba5bd8f9bc0a0d14016 upstream.

batadv_show_throughput_override() invokes batadv_hardif_get_by_netdev(),
which gets a batadv_hard_iface object from net_dev with increased refcnt
and its reference is assigned to a local pointer 'hard_iface'.

When batadv_show_throughput_override() returns, "hard_iface" becomes
invalid, so the refcount should be decreased to keep refcount balanced.

The issue happens in the normal path of
batadv_show_throughput_override(), which forgets to decrease the refcnt
increased by batadv_hardif_get_by_netdev() before the function returns,
causing a refcnt leak.

Fix this issue by calling batadv_hardif_put() before the
batadv_show_throughput_override() returns in the normal path.

Fixes: 0b5ecc6811bd ("batman-adv: add throughput override attribute to hard_ifaces")
Signed-off-by: Xiyu Yang <xiyuyang19@fudan.edu.cn>
Signed-off-by: Xin Tan <tanxin.ctf@gmail.com>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

batman-adv: fix batadv_nc_random_weight_tq

commit fd0c42c4dea54335967c5a86f15fc064235a2797 upstream.

and change to pseudorandom numbers, as this is a traffic dithering
operation that doesn't need crypto-grade.

The previous code operated in 4 steps:

1. Generate a random byte 0 <= rand_tq <= 255
2. Multiply it by BATADV_TQ_MAX_VALUE - tq
3. Divide by 255 (= BATADV_TQ_MAX_VALUE)
4. Return BATADV_TQ_MAX_VALUE - rand_tq

This would apperar to scale (BATADV_TQ_MAX_VALUE - tq) by a random
value between 0/255 and 255/255.

But!  The intermediate value between steps 3 and 4 is stored in a u8
variable.  So it's truncated, and most of the time, is less than 255, after
which the division produces 0.  Specifically, if tq is odd, the product is
always even, and can never be 255.  If tq is even, there's exactly one
random byte value that will produce a product byte of 255.

Thus, the return value is 255 (511/512 of the time) or 254 (1/512
of the time).

If we assume that the truncation is a bug, and the code is meant to scale
the input, a simpler way of looking at it is that it's returning a random
value between tq and BATADV_TQ_MAX_VALUE, inclusive.

Well, we have an optimized function for doing just that.

Fixes: 3c12de9a5c75 ("batman-adv: network coding - code and transmit packets if possible")
Signed-off-by: George Spelvin <lkml@sdf.org>
Signed-off-by: Sven Eckelmann <sven@narfation.org>
Signed-off-by: Simon Wunderlich <sw@simonwunderlich.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

KVM: VMX: Mark RCX, RDX and RSI as clobbered in vmx_vcpu_run()'s asm blob

Based on upstream commit f3689e3f17f064fd4cd5f0cb01ae2395c94f39d9.

Save RCX, RDX and RSI to fake outputs to coerce the compiler into
treating them as clobbered.  RCX in particular is likely to be reused by
the compiler to dereference the 'struct vcpu_vmx' pointer, which will
result in a null pointer dereference now that RCX is zeroed by the asm
blob.

Tag the asm() blob as volatile to prevent GCC from dropping the blob,
which is possible now that the blob has output values, all of which are
unused.

Upstream commit f3689e3f17f06 ("KVM: VMX: Save RSI to an unused output
in the vCPU-run asm blob") is not a direct equivalent of this patch. As
its shortlog states, it only tagged RSI as clobbered, whereas here RCX
and RDX are also clobbered.

In upstream at the time of the offending commit (b4be98039a92 in 4.19,
0e0ab73c9a024 upstream), the inline asm blob had previously been moved
to a dedicated helper, __vmx_vcpu_run().  For unrelated reasons,
__vmx_vcpu_run() was put into its own optimization unit, which for all
intents and purposes made it impossible to consume clobbered registers
because RCX, RDX and RSI are volatile and __vmx_vcpu_run() couldn't
itself be inlined.  In other words, the bug existed but couldn't be hit.

Similarly, the lack of "volatile" was also a bug in upstream that was
hidden by an unrelated change that exists in upstream but not in 4.19.
In this case, the asm blob also uses ASM_CALL_CONSTRAINT (marks RSP as
being an input/output constraint) in upstream to play nice with objtool
due the blob making a CALL.  In 4.19, there is no CALL and thus no
ASM_CALL_CONSTRAINT.

Furthermore, both of the lurking bugs were blasted away in upstream by
commits 5e0781df1899 ("KVM: VMX: Move vCPU-run code to a proper assembly
routine") and fc2ba5a27a1a ("KVM: VMX: Call vCPU-run asm sub-routine
from C and remove clobbering"), i.e. these bugs will never be directly
fixed in upstream.

Reported-by: Tobias Urdin <tobias.urdin@binero.com>
Fixes: b4be98039a92 ("KVM: VMX: Zero out *all* general purpose registers after VM-Exit")
Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

KVM: VMX: Explicitly reference RCX as the vmx_vcpu pointer in asm blobs

commit 051a2d3e59e51ae49fd56aef34e472832897ce46 upstream.

Use '%% " _ASM_CX"' instead of '%0' to dereference RCX, i.e. the
'struct vcpu_vmx' pointer, in the VM-Enter asm blobs of vmx_vcpu_run()
and nested_vmx_check_vmentry_hw().  Using the symbolic name means that
adding/removing an output parameter(s) requires "rewriting" almost all
of the asm blob, which makes it nearly impossible to understand what's
being changed in even the most minor patches.

Opportunistically improve the code comments.

Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>