Patch "f2fs crypto: add missing locking for keyring_key access" has been added to the 4.4-stable tree

Patch "f2fs crypto: add missing locking for keyring_key access" has been added to the 4.4-stable tree

[gregkh]

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

    f2fs crypto: add missing locking for keyring_key access

to the 4.4-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:
     f2fs-crypto-add-missing-locking-for-keyring_key-access.patch
and it can be found in the queue-4.4 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 745e8490b1e960ad79859dd8ba6a0b5a8d3d994e Mon Sep 17 00:00:00 2001
From: Jaegeuk Kim <jaegeuk@kernel.org>
Date: Fri, 5 Feb 2016 19:38:42 -0800
Subject: f2fs crypto: add missing locking for keyring_key access

From: Jaegeuk Kim <jaegeuk@kernel.org>

commit 745e8490b1e960ad79859dd8ba6a0b5a8d3d994e upstream.

This patch adopts:
	ext4 crypto: add missing locking for keyring_key access

Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 fs/f2fs/crypto_key.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/fs/f2fs/crypto_key.c
+++ b/fs/f2fs/crypto_key.c
@@ -193,9 +193,11 @@ int f2fs_get_encryption_info(struct inod
 		res = -ENOKEY;
 		goto out;
 	}
+	down_read(&keyring_key->sem);
 	ukp = user_key_payload(keyring_key);
 	if (ukp->datalen != sizeof(struct f2fs_encryption_key)) {
 		res = -EINVAL;
+		up_read(&keyring_key->sem);
 		goto out;
 	}
 	master_key = (struct f2fs_encryption_key *)ukp->data;
@@ -206,10 +208,12 @@ int f2fs_get_encryption_info(struct inod
 				"f2fs: key size incorrect: %d\n",
 				master_key->size);
 		res = -ENOKEY;
+		up_read(&keyring_key->sem);
 		goto out;
 	}
 	res = f2fs_derive_key_aes(ctx.nonce, master_key->raw,
 				  raw_key);
+	up_read(&keyring_key->sem);
 	if (res)
 		goto out;
 


Patches currently in stable-queue which might be from jaegeuk@kernel.org are

queue-4.4/fscrypto-require-write-access-to-mount-to-set-encryption-policy.patch
queue-4.4/f2fs-crypto-add-missing-locking-for-keyring_key-access.patch
queue-4.4/f2fs-crypto-replace-some-bug_on-s-with-error-checks.patch