Messages in this thread Patch in this message | | | From | Greg Kroah-Hartman <> | Subject | [PATCH 5.14 548/849] bpf: Fix propagation of signed bounds from 64-bit min/max into 32-bit. | Date | Mon, 15 Nov 2021 18:00:31 +0100 |
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From: Alexei Starovoitov <ast@kernel.org>
[ Upstream commit 388e2c0b978339dee9b0a81a2e546f8979e021e2 ]
Similar to unsigned bounds propagation fix signed bounds. The 'Fixes' tag is a hint. There is no security bug here. The verifier was too conservative.
Fixes: 3f50f132d840 ("bpf: Verifier, do explicit ALU32 bounds tracking") Signed-off-by: Alexei Starovoitov <ast@kernel.org> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Acked-by: Yonghong Song <yhs@fb.com> Link: https://lore.kernel.org/bpf/20211101222153.78759-2-alexei.starovoitov@gmail.com Signed-off-by: Sasha Levin <sashal@kernel.org> --- kernel/bpf/verifier.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index b9fb079559a6d..4dd9cedfc453d 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1397,7 +1397,7 @@ static void __reg_combine_32_into_64(struct bpf_reg_state *reg) static bool __reg64_bound_s32(s64 a) { - return a > S32_MIN && a < S32_MAX; + return a >= S32_MIN && a <= S32_MAX; } static bool __reg64_bound_u32(u64 a) -- 2.33.0
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