module: Fix display of wrong module .text address
authorThomas Richter <tmricht@linux.ibm.com>
Wed, 18 Apr 2018 07:14:36 +0000 (09:14 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Tue, 1 May 2018 19:47:28 +0000 (12:47 -0700)
commit be71eda5383faa663efdba9ef54a6b8255e3c7f0 upstream.

Reading file /proc/modules shows the correct address:
[root@s35lp76 ~]# cat /proc/modules | egrep '^qeth_l2'
qeth_l2 94208 1 - Live 0x000003ff80401000

and reading file /sys/module/qeth_l2/sections/.text
[root@s35lp76 ~]# cat /sys/module/qeth_l2/sections/.text
0x0000000018ea8363
displays a random address.

This breaks the perf tool which uses this address on s390
to calculate start of .text section in memory.

Fix this by printing the correct (unhashed) address.

Thanks to Jessica Yu for helping on this.

Fixes: ef0010a30935 ("vsprintf: don't use 'restricted_pointer()' when not restricting")
Cc: <stable@vger.kernel.org> # v4.15+
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Cc: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernel/module.c

index e42764acedb4cd35ccb81d396b1391510b52db25..bbb45c038321f3e6cd111ea9af30208adb0d211c 100644 (file)
@@ -1472,7 +1472,8 @@ static ssize_t module_sect_show(struct module_attribute *mattr,
 {
        struct module_sect_attr *sattr =
                container_of(mattr, struct module_sect_attr, mattr);
-       return sprintf(buf, "0x%pK\n", (void *)sattr->address);
+       return sprintf(buf, "0x%px\n", kptr_restrict < 2 ?
+                      (void *)sattr->address : NULL);
 }
 
 static void free_sect_attrs(struct module_sect_attrs *sect_attrs)