[PATCH 1/2] ecryptfs: Improve metatdata read failure logging

[Tim Gardner <tim.gardner@canonical.com>]

There are 3 read failure cases in ecryptfs_read_metadata(), but only 2
of them are uniquely noted by kernel log messages. This patch
identifies and logs each read failure case. It also correctly interprets
a negative return value from ecryptfs_read_lower().

Removes unnecessary variable initialization.

Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org
Cc: Tyler Hicks <tyler.hicks@canonical.com>
Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
---
 fs/ecryptfs/crypto.c |   17 +++++++++++------
 1 files changed, 11 insertions(+), 6 deletions(-)

diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index d3c8776..ac063bd 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -1590,8 +1590,8 @@ int ecryptfs_read_and_validate_xattr_region(struct dentry *dentry,
  */
 int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
 {
-	int rc = 0;
-	char *page_virt = NULL;
+	int rc;
+	char *page_virt;
 	struct inode *ecryptfs_inode = ecryptfs_dentry->d_inode;
 	struct ecryptfs_crypt_stat *crypt_stat =
 	    &ecryptfs_inode_to_private(ecryptfs_inode)->crypt_stat;
@@ -1611,10 +1611,15 @@ int ecryptfs_read_metadata(struct dentry *ecryptfs_dentry)
 	}
 	rc = ecryptfs_read_lower(page_virt, 0, crypt_stat->extent_size,
 				 ecryptfs_inode);
-	if (rc >= 0)
-		rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
-						ecryptfs_dentry,
-						ECRYPTFS_VALIDATE_HEADER_SIZE);
+	if (rc < 0) {
+		printk(KERN_ERR "%s: Could not read %u bytes\n",
+			__func__, crypt_stat->extent_size);
+		goto out;
+	}
+
+	rc = ecryptfs_read_headers_virt(page_virt, crypt_stat,
+					ecryptfs_dentry,
+					ECRYPTFS_VALIDATE_HEADER_SIZE);
 	if (rc) {
 		memset(page_virt, 0, PAGE_CACHE_SIZE);
 		rc = ecryptfs_read_xattr_region(page_virt, ecryptfs_inode);
-- 
1.7.8.3