ovl: filter of trusted xattr results in audit

When filtering xattr list for reading, presence of trusted xattr results in a security audit log. However, if there is other content no errno will be set, and if there isn't, the errno will be -ENODATA and not -EPERM as is usually associated with a lack of capability. The check does not block the request to list the xattrs present. Switch to ns_capable_noaudit to reflect a more appropriate check. Signed-off-by: Mark Salyzyn <[email protected]> Cc: [email protected] Cc: [email protected] Cc: [email protected] # v3.18+ Fixes: a082c6f ("ovl: filter trusted xattr for non-admin") Signed-off-by: Miklos Szeredi <[email protected]>
ambv · Sep 11, 2019 · 5c2e9f3 · 5c2e9f3
1 parent 97f024b
commit 5c2e9f3
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/fs/overlayfs/inode.c b/fs/overlayfs/inode.c
@@ -383,7 +383,8 @@ static bool ovl_can_list(const char *s)
 		return true;
 
 	/* Never list trusted.overlay, list other trusted for superuser only */
-	return !ovl_is_private_xattr(s) && capable(CAP_SYS_ADMIN);
+	return !ovl_is_private_xattr(s) &&
+	       ns_capable_noaudit(&init_user_ns, CAP_SYS_ADMIN);
 }
 
 ssize_t ovl_listxattr(struct dentry *dentry, char *list, size_t size)