From a1be1f3931bfe0a42b46fef77a04593c2b136e7f Mon Sep 17 00:00:00 2001 From: Eric Biggers <ebiggers@google.com> Date: Tue, 6 Feb 2018 15:40:24 -0800 Subject: [PATCH] kernel/relay.c: revert "kernel/relay.c: fix potential memory leak" 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 <ebiggers@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Reviewed-by: Andrew Morton <akpm@linux-foundation.org> Cc: Zhouyi Zhou <yizhouzhou@ict.ac.cn> Cc: Jens Axboe <axboe@kernel.dk> Cc: <stable@vger.kernel.org> [4.7+] Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> --- kernel/relay.c | 1 - 1 file changed, 1 deletion(-) diff --git a/kernel/relay.c b/kernel/relay.c index 41280033a4c52..f7f40a6e63528 100644 --- 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); -- 2.39.5