Patch "dm crypt: mark key as invalid until properly loaded" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

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

    dm crypt: mark key as invalid until properly loaded

to the 4.9-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:
     dm-crypt-mark-key-as-invalid-until-properly-loaded.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 265e9098bac02bc5e36cda21fdbad34cb5b2f48d Mon Sep 17 00:00:00 2001
From: Ondrej Kozina <okozina@redhat.com>
Date: Wed, 2 Nov 2016 15:02:08 +0100
Subject: dm crypt: mark key as invalid until properly loaded

From: Ondrej Kozina <okozina@redhat.com>

commit 265e9098bac02bc5e36cda21fdbad34cb5b2f48d upstream.

In crypt_set_key(), if a failure occurs while replacing the old key
(e.g. tfm->setkey() fails) the key must not have DM_CRYPT_KEY_VALID flag
set.  Otherwise, the crypto layer would have an invalid key that still
has DM_CRYPT_KEY_VALID flag set.

Signed-off-by: Ondrej Kozina <okozina@redhat.com>
Reviewed-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/md/dm-crypt.c |    7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

--- a/drivers/md/dm-crypt.c
+++ b/drivers/md/dm-crypt.c
@@ -1503,12 +1503,15 @@ static int crypt_set_key(struct crypt_co
 	if (!cc->key_size && strcmp(key, "-"))
 		goto out;
 
+	/* clear the flag since following operations may invalidate previously valid key */
+	clear_bit(DM_CRYPT_KEY_VALID, &cc->flags);
+
 	if (cc->key_size && crypt_decode_key(cc->key, key, cc->key_size) < 0)
 		goto out;
 
-	set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
-
 	r = crypt_setkey_allcpus(cc);
+	if (!r)
+		set_bit(DM_CRYPT_KEY_VALID, &cc->flags);
 
 out:
 	/* Hex key string not needed after here, so wipe it. */


Patches currently in stable-queue which might be from okozina@redhat.com are

queue-4.9/dm-crypt-mark-key-as-invalid-until-properly-loaded.patch