From 305197a2378ffb581f1eca3ec804f76690be7b5a Mon Sep 17 00:00:00 2001
From: Daniel Borkmann <daniel@iogearbox.net>
Date: Mon, 6 Mar 2017 13:06:00 +0100
Subject: [PATCH] bpf: test for valid type in bpf_get_work_dir
Jan-Erik reported an assertion in bpf_prog_to_subdir() failed where
type was BPF_PROG_TYPE_UNSPEC, which is only used in bpf_init_env()
to auto-mount and cache the bpf fs mount point.
Therefore, make sure when bpf_init_env() is called multiple times
(f.e. eBPF classifier with eBPF action attached) and bpf_mnt_cached
is set already that the type is also valid. In bpf_init_env(), we're
only interested in the mount point and not a type-specific subdir.
Fixes: e42256699cac ("bpf: make tc's bpf loader generic and move into lib")
Reported-by: Jan-Erik Rediger <janerik@rediger.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
(cherry picked from commit 51361a9f1cfca81259c68515cb24fbaace03136a)
---
lib/bpf.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/bpf.c b/lib/bpf.c
index 64e199b3..fef9cfcd 100644
--- a/lib/bpf.c
+++ b/lib/bpf.c
@@ -596,7 +596,7 @@ static const char *bpf_get_work_dir(enum bpf_prog_type type)
if (bpf_mnt_cached) {
const char *out = mnt;
- if (out) {
+ if (out && type) {
snprintf(bpf_tmp, sizeof(bpf_tmp), "%s%s/",
out, bpf_prog_to_subdir(type));
out = bpf_tmp;
--
2.11.0