eCryptfs: Return useful code from contains_ecryptfs_marker

Instead of having the calling functions translate the true/false return
code to either 0 or -EINVAL, have contains_ecryptfs_marker() return 0 or
-EINVAL so that the calling functions can just reuse the return code.

Also, rename the function to ecryptfs_validate_marker() to avoid callers
mistakenly thinking that it returns true/false codes.

Signed-off-by: Tyler Hicks <tyhicks@linux.vnet.ibm.com>

1 files changed, 10 insertions, 16 deletions

diff --git a/fs/ecryptfs/crypto.c b/fs/ecryptfs/crypto.c
index f48c4987a15c..162f9baf9eb5 100644
--- a/fs/ecryptfs/crypto.c
+++ b/fs/ecryptfs/crypto.c
@@ -1024,25 +1024,25 @@ out:
 }
 
 /**
- * contains_ecryptfs_marker - check for the ecryptfs marker
+ * ecryptfs_validate_marker - check for the ecryptfs marker
  * @data: The data block in which to check
  *
- * Returns one if marker found; zero if not found
+ * Returns zero if marker found; -EINVAL if not found
  */
-static int contains_ecryptfs_marker(char *data)
+static int ecryptfs_validate_marker(char *data)
 {
         u32 m_1, m_2;
 
         m_1 = get_unaligned_be32(data);
         m_2 = get_unaligned_be32(data + 4);
         if ((m_1 ^ MAGIC_ECRYPTFS_MARKER) == m_2)
-                return 1;
+                return 0;
         ecryptfs_printk(KERN_DEBUG, "m_1 = [0x%.8x]; m_2 = [0x%.8x]; "
                         "MAGIC_ECRYPTFS_MARKER = [0x%.8x]\n", m_1, m_2,
                         MAGIC_ECRYPTFS_MARKER);
         ecryptfs_printk(KERN_DEBUG, "(m_1 ^ MAGIC_ECRYPTFS_MARKER) = "
                         "[0x%.8x]\n", (m_1 ^ MAGIC_ECRYPTFS_MARKER));
-        return 0;
+        return -EINVAL;
 }
 
 struct ecryptfs_flag_map_elem {
@@ -1217,10 +1217,7 @@ int ecryptfs_read_and_validate_header_region(char *data,
                        __func__, rc);
                 goto out;
         }
-        if (!contains_ecryptfs_marker(data + ECRYPTFS_FILE_SIZE_BYTES)) {
-                rc = -EINVAL;
-        } else
-                rc = 0;
+        rc = ecryptfs_validate_marker(data + ECRYPTFS_FILE_SIZE_BYTES);
 out:
         return rc;
 }
@@ -1496,11 +1493,9 @@ static int ecryptfs_read_headers_virt(char *page_virt,
         crypt_stat->mount_crypt_stat = &ecryptfs_superblock_to_private(
                 ecryptfs_dentry->d_sb)->mount_crypt_stat;
         offset = ECRYPTFS_FILE_SIZE_BYTES;
-        rc = contains_ecryptfs_marker(page_virt + offset);
-        if (rc == 0) {
-                rc = -EINVAL;
+        rc = ecryptfs_validate_marker(page_virt + offset);
+        if (rc)
                 goto out;
-        }
         if (!(crypt_stat->flags & ECRYPTFS_I_SIZE_INITIALIZED))
                 ecryptfs_i_size_init(page_virt, ecryptfs_dentry->d_inode);
         offset += MAGIC_ECRYPTFS_MARKER_SIZE_BYTES;
@@ -1575,11 +1570,10 @@ int ecryptfs_read_and_validate_xattr_region(char *page_virt,
         rc = ecryptfs_read_xattr_region(page_virt, inode);
         if (rc)
                 goto out;
-        if (!contains_ecryptfs_marker(page_virt + ECRYPTFS_FILE_SIZE_BYTES)) {
+        rc = ecryptfs_validate_marker(page_virt + ECRYPTFS_FILE_SIZE_BYTES);
+        if (rc)
                 printk(KERN_WARNING "Valid data found in [%s] xattr, but "
                         "the marker is invalid\n", ECRYPTFS_XATTR_NAME);
-                rc = -EINVAL;
-        }
 out:
         return rc;
 }