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 d4593571c4049b8d046f53f81f8e17911a21e0c9..71a9429fdbb5275643082d12573911a59b532afe 100644 (file)
--- 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");