[PATCH v3 3/7] jffs2: Add missing capability check for listing trusted xattrs

[Andreas Gruenbacher]

The vfs checks if a task has the appropriate access for get and set
operations, but it cannot do that for the list operation; the file system
must check for that itself.

Signed-off-by: Andreas Gruenbacher <agruenba at redhat.com>
Reviewed-by: Christoph Hellwig <hch at lst.de>
Cc: David Woodhouse <dwmw2 at infradead.org>
Cc: linux-mtd at lists.infradead.org
---
 fs/jffs2/xattr_trusted.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/fs/jffs2/xattr_trusted.c b/fs/jffs2/xattr_trusted.c
index ceaf9c6..bbd20c1 100644
--- a/fs/jffs2/xattr_trusted.c
+++ b/fs/jffs2/xattr_trusted.c
@@ -39,6 +39,9 @@ static size_t jffs2_trusted_listxattr(struct dentry *dentry, char *list,
 {
 	size_t retlen = XATTR_TRUSTED_PREFIX_LEN + name_len + 1;
 
+	if (!capable(CAP_SYS_ADMIN))
+		return 0;
+
 	if (list && retlen<=list_size) {
 		strcpy(list, XATTR_TRUSTED_PREFIX);
 		strcpy(list + XATTR_TRUSTED_PREFIX_LEN, name);
-- 
2.5.0