From 85d31dd07002315c0d1816543fdc392c8cc6b73a Mon Sep 17 00:00:00 2001 From: Martin KaFai Lau Date: Wed, 6 Nov 2019 17:46:40 -0800 Subject: bpf: Account for insn->off when doing bpf_probe_read_kernel In the bpf interpreter mode, bpf_probe_read_kernel is used to read from PTR_TO_BTF_ID's kernel object. It currently missed considering the insn->off. This patch fixes it. Fixes: 2a02759ef5f8 ("bpf: Add support for BTF pointers to interpreter") Signed-off-by: Martin KaFai Lau Signed-off-by: Alexei Starovoitov Acked-by: Andrii Nakryiko Link: https://lore.kernel.org/bpf/20191107014640.384083-1-kafai@fb.com --- kernel/bpf/core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/bpf/core.c') diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 97e37d82a1cc..c1fde0303280 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -1569,7 +1569,7 @@ out: #undef LDST #define LDX_PROBE(SIZEOP, SIZE) \ LDX_PROBE_MEM_##SIZEOP: \ - bpf_probe_read_kernel(&DST, SIZE, (const void *)(long) SRC); \ + bpf_probe_read_kernel(&DST, SIZE, (const void *)(long) (SRC + insn->off)); \ CONT; LDX_PROBE(B, 1) LDX_PROBE(H, 2) -- cgit v1.2.3-59-g8ed1b