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| author | Alexei Starovoitov <ast@kernel.org> | 2024-06-17 10:45:47 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2024-06-17 10:45:56 -0700 |
| commit | bfbcb2c9d2978a28e9f0a77100170dc14fcf7c79 (patch) | |
| tree | 9bf05bfc8d552c7b5dff0f0698c96f25cf90009a /kernel | |
| parent | 143492fce36161402fa2f45a0756de7ff69c366a (diff) | |
| parent | a62293c33b058415237c55058a6d20de313a2e61 (diff) | |
Merge branch 'bpf-fix-missed-var_off-related-to-movsx-in-verifier'
Yonghong Song says:
====================
bpf: Fix missed var_off related to movsx in verifier
Zac reported a verification issue ([1]) where verification unexpectedly succeeded.
This is due to missing proper var_off setting in verifier related to
movsx insn. I found another similar issue as well. This patch set fixed
both problems and added three inline asm tests to test these fixes.
[1] https://lore.kernel.org/bpf/CAADnVQLPU0Shz7dWV4bn2BgtGdxN3uFHPeobGBA72tpg5Xoykw@mail.gmail.com/
====================
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20240615174621.3994321-1-yonghong.song@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/verifier.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 010cfee7ffe9..e0a398a97d32 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -6236,6 +6236,7 @@ static void set_sext32_default_val(struct bpf_reg_state *reg, int size) } reg->u32_min_value = 0; reg->u32_max_value = U32_MAX; + reg->var_off = tnum_subreg(tnum_unknown); } static void coerce_subreg_to_size_sx(struct bpf_reg_state *reg, int size) @@ -6280,6 +6281,7 @@ static void coerce_subreg_to_size_sx(struct bpf_reg_state *reg, int size) reg->s32_max_value = s32_max; reg->u32_min_value = (u32)s32_min; reg->u32_max_value = (u32)s32_max; + reg->var_off = tnum_subreg(tnum_range(s32_min, s32_max)); return; } |