Patch "kernel/relay.c: revert "kernel/relay.c: fix potential memory leak"" has been added to the 4.15-stable tree

This is a note to let you know that I've just added the patch titled

kernel/relay.c: revert "kernel/relay.c: fix potential memory leak"

to the 4.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
kernel-relay.c-revert-kernel-relay.c-fix-potential-memory-leak.patch
and it can be found in the queue-4.15 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From: Eric Biggers <[email protected]>
Date: Tue, 6 Feb 2018 15:40:24 -0800
Subject: kernel/relay.c: revert "kernel/relay.c: fix potential memory leak"

From: Eric Biggers <[email protected]>

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.

---
 kernel/relay.c |    1 -
 1 file changed, 1 deletion(-)

@@ -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);

Patches currently in stable-queue which might be from [email protected] are

queue-4.15/pipe-fix-off-by-one-error-when-checking-buffer-limits.patch queue-4.15/crypto-hash-annotate-algorithms-taking-optional-key.patch queue-4.15/crypto-cryptd-pass-through-absence-of-setkey.patch queue-4.15/crypto-hash-prevent-using-keyed-hashes-without-setting-key.patch queue-4.15/ubifs-free-the-encrypted-symlink-target.patch queue-4.15/pipe-actually-allow-root-to-exceed-the-pipe-buffer-limits.patch queue-4.15/kernel-relay.c-revert-kernel-relay.c-fix-potential-memory-leak.patch queue-4.15/nfs-reject-request-for-id_legacy-key-without-auxdata.patch queue-4.15/crypto-poly1305-remove-setkey-method.patch queue-4.15/crypto-sha512-mb-initialize-pending-lengths-correctly.patch queue-4.15/crypto-hash-introduce-crypto_hash_alg_has_setkey.patch queue-4.15/crypto-mcryptd-pass-through-absence-of-setkey.patch