lib/bpf: Don't leak fp in bpf_find_mntpt()

If fopen() succeeded but len != PATH_MAX, the function leaks the open
FILE pointer. Fix this by checking len value before calling fopen().

Signed-off-by: Phil Sutter <phil@nwl.cc>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/lib/bpf.c b/lib/bpf.c
index 4f52ad4a8f0233f11f75fff61f22463529b05a05..1dcb261dc915ff9d7446a5e0385a2648b0545e8c 100644 (file)
--- a/lib/bpf.c
+++ b/lib/bpf.c
@@ -537,8 +537,11 @@ static const char *bpf_find_mntpt(const char *fstype, unsigned long magic,
                }
        }
 
+       if (len != PATH_MAX)
+               return NULL;
+
        fp = fopen("/proc/mounts", "r");
-       if (fp == NULL || len != PATH_MAX)
+       if (fp == NULL)
                return NULL;
 
        while (fscanf(fp, "%*s %" textify(PATH_MAX) "s %99s %*s %*d %*d\n",