From: Sanidhya Kashyap <sanidhya.gatech@gmail.com>
Date: Fri, 4 Sep 2015 22:44:08 +0000 (-0700)
Subject: ocfs2: trusted xattr missing CAP_SYS_ADMIN check
X-Git-Url: http://git.lede-project.org./?a=commitdiff_plain;h=0f5e7b41f91814447defc34e915fc5d6e52266d9;p=openwrt%2Fstaging%2Fblogic.git

ocfs2: trusted xattr missing CAP_SYS_ADMIN check

The trusted extended attributes are only visible to the process which
hvae CAP_SYS_ADMIN capability but the check is missing in ocfs2
xattr_handler trusted list.  The check is important because this will be
used for implementing mechanisms in the userspace for which other
ordinary processes should not have access to.

Signed-off-by: Sanidhya Kashyap <sanidhya.gatech@gmail.com>
Reviewed-by: Mark Fasheh <mfasheh@suse.de>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Taesoo kim <taesoo@gatech.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---

diff --git a/fs/ocfs2/xattr.c b/fs/ocfs2/xattr.c
index 889f3796a0d7..a24f264b2fc4 100644
--- a/fs/ocfs2/xattr.c
+++ b/fs/ocfs2/xattr.c
@@ -7334,6 +7334,9 @@ static size_t ocfs2_xattr_trusted_list(struct dentry *dentry, char *list,
 	const size_t prefix_len = XATTR_TRUSTED_PREFIX_LEN;
 	const size_t total_len = prefix_len + name_len + 1;
 
+	if (!capable(CAP_SYS_ADMIN))
+		return 0;
+
 	if (list && total_len <= list_size) {
 		memcpy(list, XATTR_TRUSTED_PREFIX, prefix_len);
 		memcpy(list + prefix_len, name, name_len);