evm: fix potential race when removing xattrs

EVM needs to be atomically updated when removing xattrs.
Otherwise concurrent EVM verification may fail in between.
This patch fixes by moving i_mutex unlocking after calling
EVM hook. fsnotify_xattr() is also now called while locked
the same way as it is done in __vfs_setxattr_noperm.

Changelog:
- remove unused 'inode' variable.

Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>

1 files changed, 5 insertions, 5 deletions

diff --git a/fs/xattr.c b/fs/xattr.c
index 4ef6985..072fee1 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -298,18 +298,18 @@ vfs_removexattr(struct dentry *dentry, const char *name)
 
 	mutex_lock(&inode->i_mutex);
 	error = security_inode_removexattr(dentry, name);
-	if (error) {
-		mutex_unlock(&inode->i_mutex);
-		return error;
-	}
+	if (error)
+		goto out;
 
 	error = inode->i_op->removexattr(dentry, name);
-	mutex_unlock(&inode->i_mutex);
 
 	if (!error) {
 		fsnotify_xattr(dentry);
 		evm_inode_post_removexattr(dentry, name);
 	}
+
+out:
+	mutex_unlock(&inode->i_mutex);
 	return error;
 }
 EXPORT_SYMBOL_GPL(vfs_removexattr);