bpf, selftests: Fix up some test_verifier cases for unprivileged
authorPiotr Krysiuk <piotras@gmail.com>
Tue, 16 Mar 2021 10:44:42 +0000 (11:44 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Sat, 20 Mar 2021 09:43:43 +0000 (10:43 +0100)
commit 0a13e3537ea67452d549a6a80da3776d6b7dedb3 upstream.

Fix up test_verifier error messages for the case where the original error
message changed, or for the case where pointer alu errors differ between
privileged and unprivileged tests. Also, add alternative tests for keeping
coverage of the original verifier rejection error message (fp alu), and
newly reject map_ptr += rX where rX == 0 given we now forbid alu on these
types for unprivileged. All test_verifier cases pass after the change. The
test case fixups were kept separate to ease backporting of core changes.

Signed-off-by: Piotr Krysiuk <piotras@gmail.com>
Co-developed-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
tools/testing/selftests/bpf/verifier/bounds_deduction.c
tools/testing/selftests/bpf/verifier/map_ptr.c
tools/testing/selftests/bpf/verifier/unpriv.c
tools/testing/selftests/bpf/verifier/value_ptr_arith.c

index 1fd07a4f27ac215a5fd8f258c13079793b2a0e0e..c162498a64fc6a0644903bde7255304690af66b7 100644 (file)
@@ -6,8 +6,9 @@
                BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
                BPF_EXIT_INSN(),
        },
-       .result = REJECT,
+       .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types",
        .errstr = "R0 tried to subtract pointer from scalar",
+       .result = REJECT,
 },
 {
        "check deducing bounds from const, 2",
@@ -20,6 +21,8 @@
                BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_0),
                BPF_EXIT_INSN(),
        },
+       .errstr_unpriv = "R1 tried to sub from different maps, paths, or prohibited types",
+       .result_unpriv = REJECT,
        .result = ACCEPT,
        .retval = 1,
 },
@@ -31,8 +34,9 @@
                BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
                BPF_EXIT_INSN(),
        },
-       .result = REJECT,
+       .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types",
        .errstr = "R0 tried to subtract pointer from scalar",
+       .result = REJECT,
 },
 {
        "check deducing bounds from const, 4",
@@ -45,6 +49,8 @@
                BPF_ALU64_REG(BPF_SUB, BPF_REG_1, BPF_REG_0),
                BPF_EXIT_INSN(),
        },
+       .errstr_unpriv = "R1 tried to sub from different maps, paths, or prohibited types",
+       .result_unpriv = REJECT,
        .result = ACCEPT,
 },
 {
@@ -55,8 +61,9 @@
                BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
                BPF_EXIT_INSN(),
        },
-       .result = REJECT,
+       .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types",
        .errstr = "R0 tried to subtract pointer from scalar",
+       .result = REJECT,
 },
 {
        "check deducing bounds from const, 6",
@@ -67,8 +74,9 @@
                BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
                BPF_EXIT_INSN(),
        },
-       .result = REJECT,
+       .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types",
        .errstr = "R0 tried to subtract pointer from scalar",
+       .result = REJECT,
 },
 {
        "check deducing bounds from const, 7",
@@ -80,8 +88,9 @@
                            offsetof(struct __sk_buff, mark)),
                BPF_EXIT_INSN(),
        },
-       .result = REJECT,
+       .errstr_unpriv = "R1 tried to sub from different maps, paths, or prohibited types",
        .errstr = "dereference of modified ctx ptr",
+       .result = REJECT,
        .flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
                            offsetof(struct __sk_buff, mark)),
                BPF_EXIT_INSN(),
        },
-       .result = REJECT,
+       .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types",
        .errstr = "dereference of modified ctx ptr",
+       .result = REJECT,
        .flags = F_NEEDS_EFFICIENT_UNALIGNED_ACCESS,
 },
 {
                BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
                BPF_EXIT_INSN(),
        },
-       .result = REJECT,
+       .errstr_unpriv = "R0 tried to sub from different maps, paths, or prohibited types",
        .errstr = "R0 tried to subtract pointer from scalar",
+       .result = REJECT,
 },
 {
        "check deducing bounds from const, 10",
                BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
                BPF_EXIT_INSN(),
        },
-       .result = REJECT,
        .errstr = "math between ctx pointer and register with unbounded min value is not allowed",
+       .result = REJECT,
 },
index 637f9293bda846bcf5687656007574473ce3a614..92a1dc8e17462b3e82e2cc797d3908b117367004 100644 (file)
@@ -74,6 +74,8 @@
        BPF_EXIT_INSN(),
        },
        .fixup_map_hash_16b = { 4 },
+       .result_unpriv = REJECT,
+       .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types",
        .result = ACCEPT,
 },
 {
@@ -90,5 +92,7 @@
        BPF_EXIT_INSN(),
        },
        .fixup_map_hash_16b = { 4 },
+       .result_unpriv = REJECT,
+       .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types",
        .result = ACCEPT,
 },
index 91bb77c24a2ef3bb392ce2763e90d7a05f2af34d..0d621c841db143d12f36ef2c5eb7a3a48463c51c 100644 (file)
        .result = ACCEPT,
 },
 {
-       "unpriv: adding of fp",
+       "unpriv: adding of fp, reg",
        .insns = {
        BPF_MOV64_IMM(BPF_REG_0, 0),
        BPF_MOV64_IMM(BPF_REG_1, 0),
        BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, -8),
        BPF_EXIT_INSN(),
        },
+       .errstr_unpriv = "R1 tried to add from different maps, paths, or prohibited types",
+       .result_unpriv = REJECT,
+       .result = ACCEPT,
+},
+{
+       "unpriv: adding of fp, imm",
+       .insns = {
+       BPF_MOV64_IMM(BPF_REG_0, 0),
+       BPF_MOV64_REG(BPF_REG_1, BPF_REG_10),
+       BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, 0),
+       BPF_STX_MEM(BPF_DW, BPF_REG_1, BPF_REG_0, -8),
+       BPF_EXIT_INSN(),
+       },
        .errstr_unpriv = "R1 stack pointer arithmetic goes out of range",
        .result_unpriv = REJECT,
        .result = ACCEPT,
index ed4e76b246499a3c8f96d88aa52eca377a335360..feb91266db39a09cf78f21d34666fd129b0684fb 100644 (file)
        .fixup_map_array_48b = { 1 },
        .result = ACCEPT,
        .result_unpriv = REJECT,
-       .errstr_unpriv = "R2 tried to add from different maps or paths",
+       .errstr_unpriv = "R2 tried to add from different maps, paths, or prohibited types",
        .retval = 0,
 },
 {
        .result = ACCEPT,
        .retval = 0xabcdef12,
 },
+{
+       "map access: value_ptr += N, value_ptr -= N known scalar",
+       .insns = {
+       BPF_ST_MEM(BPF_DW, BPF_REG_10, -8, 0),
+       BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
+       BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
+       BPF_LD_MAP_FD(BPF_REG_1, 0),
+       BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_map_lookup_elem),
+       BPF_JMP_IMM(BPF_JEQ, BPF_REG_0, 0, 6),
+       BPF_MOV32_IMM(BPF_REG_1, 0x12345678),
+       BPF_STX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, 0),
+       BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 2),
+       BPF_MOV64_IMM(BPF_REG_1, 2),
+       BPF_ALU64_REG(BPF_SUB, BPF_REG_0, BPF_REG_1),
+       BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_0, 0),
+       BPF_EXIT_INSN(),
+       },
+       .fixup_map_array_48b = { 3 },
+       .result = ACCEPT,
+       .retval = 0x12345678,
+},
 {
        "map access: unknown scalar += value_ptr, 1",
        .insns = {