From: Stijn Tintel <stijn@linux-ipv6.be>
Date: Tue, 21 Dec 2021 17:37:03 +0000 (+0200)
Subject: libfstools: avoid segfault in find_mount_point
X-Git-Url: http://git.openwrt.org/?a=commitdiff_plain;h=922f1b3c091dbe12af4ba12a76ba8563418b688c;p=project%2Ffstools.git

libfstools: avoid segfault in find_mount_point

If block is NULL, find_mount_point will segfault when comparing it
against the device name found in /proc/self/mountinfo. Avoid this by
checking if block is NULL.

Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
---

diff --git a/libfstools/find.c b/libfstools/find.c
index cefdd23..1d91c51 100644
--- a/libfstools/find.c
+++ b/libfstools/find.c
@@ -109,6 +109,9 @@ find_mount_point(char *block, int root_only)
 	int rstat;
 	unsigned int minor, major;
 
+	if (!block)
+		return NULL;
+
 	if (!fp)
 		return NULL;