From: Jaegeuk Kim <jaegeuk@kernel.org>
Date: Sat, 6 Feb 2016 03:38:42 +0000 (-0800)
Subject: f2fs crypto: add missing locking for keyring_key access
X-Git-Tag: v4.4.95~5
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=7d9e13d953f2a3029d8b26a6f9a7dae83a4594ae;p=thirdparty%2Fkernel%2Fstable.git

f2fs crypto: add missing locking for keyring_key access

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>
---

diff --git a/fs/f2fs/crypto_key.c b/fs/f2fs/crypto_key.c
index 81c87f7a32519..ae49be377b606 100644
--- a/fs/f2fs/crypto_key.c
+++ b/fs/f2fs/crypto_key.c
@@ -193,9 +193,11 @@ int f2fs_get_encryption_info(struct inode *inode)
 		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 inode *inode)
 				"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;