From: Zhang Zhen <zhenzhang.zhang@huawei.com>
Date: Mon, 12 May 2014 13:57:59 +0000 (-0400)
Subject: ext4: avoid unneeded lookup when xattr name is invalid
X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=230b8c1a7b388ac5e06549a7dbe083568875804e;p=linux-beck.git

ext4: avoid unneeded lookup when xattr name is invalid

In ext4_xattr_set_handle() we have checked the xattr name's length. So
we should also check it in ext4_xattr_get() to avoid unneeded lookup
caused by invalid name.

Signed-off-by: Zhang Zhen <zhenzhang.zhang@huawei.com>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
---

diff --git a/fs/ext4/xattr.c b/fs/ext4/xattr.c
index 4eec399ec807..c6ae6fab99be 100644
--- a/fs/ext4/xattr.c
+++ b/fs/ext4/xattr.c
@@ -369,6 +369,9 @@ ext4_xattr_get(struct inode *inode, int name_index, const char *name,
 {
 	int error;
 
+	if (strlen(name) > 255)
+		return -ERANGE;
+
 	down_read(&EXT4_I(inode)->xattr_sem);
 	error = ext4_xattr_ibody_get(inode, name_index, name, buffer,
 				     buffer_size);