[CRIU] [PATCH 3/9] read_ns_sys_file(): don't overrun buf

[Kir Kolyshkin]

This is a classical off-by-one error. If sizeof(buf) is 512,
the last element is buf[511] but not buf[512].

Note that if read() returns 0, we return 0 but buf stays
uninitialized.

Reported by Coverity, CID 114623.

Signed-off-by: Kir Kolyshkin <kir at openvz.org>
---
 net.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net.c b/net.c
index 96f2fcc..08ef865 100644
--- a/net.c
+++ b/net.c
@@ -45,8 +45,8 @@ int read_ns_sys_file(char *path, char *buf, int len)
 	rlen = read(fd, buf, len);
 	close(fd);
 
-	if (rlen >= 0)
-		buf[rlen] = '\0';
+	if (rlen > 0)
+		buf[rlen - 1] = '\0';
 
 	return rlen;
 }
-- 
2.4.3