From: Eric Biggers ebiggers@google.com Subject: kernel/relay.c: revert "kernel/relay.c: fix potential memory leak"
This reverts ba62bafe942b159a6 ("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 ---
kernel/relay.c | 1 - 1 file changed, 1 deletion(-)
diff -puN kernel/relay.c~revert-kernel-relayc-fix-potential-memory-leak kernel/relay.c --- a/kernel/relay.c~revert-kernel-relayc-fix-potential-memory-leak +++ a/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); _