From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Eric Biggers , syzbot , Andrew Morton , Zhouyi Zhou , Jens Axboe , Linus Torvalds Subject: [PATCH 4.15 158/202] kernel/relay.c: revert "kernel/relay.c: fix potential memory leak" Date: Thu, 15 Feb 2018 16:17:38 +0100 Message-Id: <20180215151721.162546627@linuxfoundation.org> In-Reply-To: <20180215151712.768794354@linuxfoundation.org> References: <20180215151712.768794354@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Eric Biggers commit a1be1f3931bfe0a42b46fef77a04593c2b136e7f upstream. This reverts commit ba62bafe942b ("kernel/relay.c: fix potential memory leak"). This commit introduced a double free bug, because 'chan' is already freed by the line: kref_put(&chan->kref, relay_destroy_channel); This bug was found by syzkaller, using the BLKTRACESETUP ioctl. Link: http://lkml.kernel.org/r/20180127004759.101823-1-ebiggers3@gmail.com Fixes: ba62bafe942b ("kernel/relay.c: fix potential memory leak") Signed-off-by: Eric Biggers Reported-by: syzbot Reviewed-by: Andrew Morton Cc: Zhouyi Zhou Cc: Jens Axboe Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- kernel/relay.c | 1 - 1 file changed, 1 deletion(-) --- a/kernel/relay.c +++ b/kernel/relay.c @@ -611,7 +611,6 @@ free_bufs: kref_put(&chan->kref, relay_destroy_channel); mutex_unlock(&relay_channels_mutex); - kfree(chan); return NULL; } EXPORT_SYMBOL_GPL(relay_open);