From d0f2fd36292ebf7787c8a2344216f58f48bdcf66 Mon Sep 17 00:00:00 2001 From: Tomas Bortoli Date: Tue, 10 Jul 2018 00:29:43 +0200 Subject: [PATCH] net/9p/client.c: version pointer uninitialized commit 7913690dcc5e18e235769fd87c34143072f5dbea upstream. The p9_client_version() does not initialize the version pointer. If the call to p9pdu_readf() returns an error and version has not been allocated in p9pdu_readf(), then the program will jump to the "error" label and will try to free the version pointer. If version is not initialized, free() will be called with uninitialized, garbage data and will provoke a crash. Link: http://lkml.kernel.org/r/20180709222943.19503-1-tomasbortoli@gmail.com Signed-off-by: Tomas Bortoli Reported-by: syzbot+65c6b72f284a39d416b4@syzkaller.appspotmail.com Reviewed-by: Jun Piao Reviewed-by: Yiwen Jiang Cc: Eric Van Hensbergen Cc: Ron Minnich Cc: Latchesar Ionkov Signed-off-by: Andrew Morton Signed-off-by: Dominique Martinet Signed-off-by: Ben Hutchings --- net/9p/client.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/9p/client.c b/net/9p/client.c index 90295cc94b82..d150562c4172 100644 --- a/net/9p/client.c +++ b/net/9p/client.c @@ -938,7 +938,7 @@ static int p9_client_version(struct p9_client *c) { int err = 0; struct p9_req_t *req; - char *version; + char *version = NULL; int msize; p9_debug(P9_DEBUG_9P, ">>> TVERSION msize %d protocol %d\n",