From: Alexei Starovoitov <ast@fb.com>
Date: Fri, 1 Dec 2017 05:31:35 +0000 (-0800)
Subject: bpf: fix stack state printing in verifier log
X-Git-Tag: v4.19~1702^2~431^2~2^2~6
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=12a3cc8424fe1237aaeb982dec4f0914ddd22f3e;p=platform%2Fkernel%2Flinux-rpi3.git

bpf: fix stack state printing in verifier log

fix incorrect stack state prints in print_verifier_state()

Fixes: 638f5b90d460 ("bpf: reduce verifier memory consumption")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
---

diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index d459357..71a9429f 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -279,7 +279,7 @@ static void print_verifier_state(struct bpf_verifier_env *env,
 	for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
 		if (state->stack[i].slot_type[0] == STACK_SPILL)
 			verbose(env, " fp%d=%s",
-				-MAX_BPF_STACK + i * BPF_REG_SIZE,
+				(-i - 1) * BPF_REG_SIZE,
 				reg_type_str[state->stack[i].spilled_ptr.type]);
 	}
 	verbose(env, "\n");