WTF: patch "[PATCH] fscrypt: fix the test_dummy_encryption mount option" was seriously submitted to be applied to the 4.9-stable tree?

The patch below was submitted to be applied to the 4.9-stable tree.

I fail to see how this patch meets the stable kernel rules as found at Documentation/stable_kernel_rules.txt.

I could be totally wrong, and if so, please respond to <[email protected]> and let me know why this patch should be applied. Otherwise, it is now dropped from my patch queues, never to be seen again.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From: Theodore Ts'o <[email protected]>
Date: Tue, 27 Dec 2016 19:46:27 -0500
Subject: [PATCH] fscrypt: fix the test_dummy_encryption mount option

Commit f1c131b45410a: "crypto: xts - Convert to skcipher" now fails the setkey operation if the AES key is the same as the tweak key. Previously this check was only done if FIPS mode is enabled. Now this check is also done if weak key checking was requested. This is reasonable, but since we were using the dummy key which was a constant series of 0x42 bytes, it now caused dummy encrpyption test mode to fail.

Fix this by using 0x42... and 0x24... for the two keys, so they are different.

index 6eeea1dcba41..95cd4c3b06c3 100644
@@ -248,7 +248,8 @@ retry:
 		goto out;
 
 	if (fscrypt_dummy_context_enabled(inode)) {
-		memset(raw_key, 0x42, FS_AES_256_XTS_KEY_SIZE);
+		memset(raw_key, 0x42, keysize/2);
+		memset(raw_key+keysize/2, 0x24, keysize - (keysize/2));
 		goto got_key;
 	}
 

Yes, I screwed up, sorry. I added the Fixes line, and then later said, "hmm, there's a fixes line, I should add a cc: stable" line.

Technically the bug *does* exist in 4.9 and older kernels, and was only exposed post-4.9, but it's for a testing option that no one should care about in production anyway. So there's no need for this to be in the stable trees.

Cheers,

- Ted