From: Christian Brauner <christian.brauner@ubuntu.com>
Date: Sun, 10 Sep 2017 04:42:10 +0000 (+0200)
Subject: utils: do not write to 0 sized buffer
X-Git-Tag: lxc-2.0.9~33
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=c04e54bd462e8581ede9aa175e2b88ad15a800a5;p=thirdparty%2Flxc.git

utils: do not write to 0 sized buffer

Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
---

diff --git a/src/lxc/utils.c b/src/lxc/utils.c
index 959481ee2..7cc68d8d2 100644
--- a/src/lxc/utils.c
+++ b/src/lxc/utils.c
@@ -2327,9 +2327,11 @@ int run_command(char *buf, size_t buf_size, int (*child_fn)(void *), void *args)
 	/* close the write-end of the pipe */
 	close(pipefd[1]);
 
-	bytes = read(pipefd[0], buf, (buf_size > 0) ? (buf_size - 1) : 0);
-	if (bytes > 0)
-		buf[bytes - 1] = '\0';
+	if (buf && buf_size > 0) {
+		bytes = read(pipefd[0], buf, buf_size - 1);
+		if (bytes > 0)
+			buf[bytes - 1] = '\0';
+	}
 
 	fret = wait_for_pid(child);
 	/* close the read-end of the pipe */