From 85614894812adb00ddd1eb3e4b18ddb995dd61c1 Mon Sep 17 00:00:00 2001
From: Alexei Starovoitov <ast@fb.com>
Date: Wed, 3 Apr 2019 18:39:04 +0000
Subject: [PATCH] bpf: fix stack state printing in verifier log

commit 12a3cc8424fe1237aaeb982dec4f0914ddd22f3e upstream.

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>
Signed-off-by: Balbir Singh <sblbir@amzn.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.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 68ff8ee42ba0..84e0338be0ad 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -268,7 +268,7 @@ static void print_verifier_state(struct bpf_verifier_state *state)
 	for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) {
 		if (state->stack[i].slot_type[0] == STACK_SPILL)
 			verbose(" 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("\n");