From: Andy Lutomirski <[email protected]> 3.12-stable review patch. If anyone has any objections, please let me know.
=============== commit a1480dcc3c706e309a88884723446f2e84fedd5b upstream. Accessing do_remount_sb should require global CAP_SYS_ADMIN, but only one of the two call sites was appropriately protected. Fixes CVE-2014-7975. Signed-off-by: Andy Lutomirski <[email protected]> Signed-off-by: Jiri Slaby <[email protected]> --- fs/namespace.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/fs/namespace.c b/fs/namespace.c index 4ea2b7378d8c..4b14bfc4cfce 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1277,6 +1277,8 @@ static int do_umount(struct mount *mnt, int flags) * Special case for "unmounting" root ... * we just try to remount it readonly. */ + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; down_write(&sb->s_umount); if (!(sb->s_flags & MS_RDONLY)) retval = do_remount_sb(sb, MS_RDONLY, NULL, 0); -- 2.1.2 -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
