From: Lennart Poettering <lennart@poettering.net>
Date: Sun, 29 Jun 2014 20:15:33 +0000 (+0200)
Subject: util: refuse considering UID 0xFFFF and 0xFFFFFFFF valid
X-Git-Tag: v215~119
X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=306a55c86360a7ae7b2509771d5ea6ab0d166d85

util: refuse considering UID 0xFFFF and 0xFFFFFFFF valid
---

diff --git a/src/shared/util.c b/src/shared/util.c
index e7ff0f884..1709bb70c 100644
--- a/src/shared/util.c
+++ b/src/shared/util.c
@@ -280,6 +280,14 @@ int parse_uid(const char *s, uid_t* ret_uid) {
         if ((unsigned long) uid != ul)
                 return -ERANGE;
 
+        /* Some libc APIs use (uid_t) -1 as special placeholder */
+        if (uid == (uid_t) 0xFFFFFFFF)
+                return -EINVAL;
+
+        /* A long time ago UIDs where 16bit, hence explicitly avoid the 32bit -1 too */
+        if (uid == (uid_t) 0xFFFF)
+                return -EINVAL;
+
         *ret_uid = uid;
         return 0;
 }