From 929aa5b250bfc59aca492d3213c7f3a53e2a5247 Mon Sep 17 00:00:00 2001
From: Josh Triplett <josh@joshtriplett.org>
Date: Thu, 14 May 2015 15:17:01 -0700
Subject: [PATCH] uidgid: make uid_valid and gid_valid work with
!CONFIG_MULTIUSER
{u,g}id_valid call {u,g}id_eq, which calls __k{u,g}id_val on both
arguments and compares. With !CONFIG_MULTIUSER, __k{u,g}id_val return a
constant 0, which makes {u,g}id_valid always return false. Change
{u,g}id_valid to compare their argument against -1 instead. That produces
identical results in the normal CONFIG_MULTIUSER=y case, but with
!CONFIG_MULTIUSER will make {u,g}id_valid constant-fold into "return
true;" rather than "return false;".
This fixes uses of devpts without CONFIG_MULTIUSER.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Reported-by: Fengguang Wu <fengguang.wu@intel.com>,
Cc: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
---
include/linux/uidgid.h | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/include/linux/uidgid.h b/include/linux/uidgid.h
index 0ee05da388994..03835522dfcb6 100644
--- a/include/linux/uidgid.h
+++ b/include/linux/uidgid.h
@@ -109,12 +109,12 @@ static inline bool gid_lte(kgid_t left, kgid_t right)
static inline bool uid_valid(kuid_t uid)
{
- return !uid_eq(uid, INVALID_UID);
+ return __kuid_val(uid) != (uid_t) -1;
}
static inline bool gid_valid(kgid_t gid)
{
- return !gid_eq(gid, INVALID_GID);
+ return __kgid_val(gid) != (gid_t) -1;
}
#ifdef CONFIG_USER_NS
--
2.30.2