From: Lennart Poettering <lennart@poettering.net>
Date: Thu, 7 Mar 2019 09:52:35 +0000 (+0100)
Subject: user-util: paranoia — add overflow check on ERANGE loop
X-Git-Tag: v242-rc1~155^2~7
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=47436d30bb117d85149b1764733bd0ed8a53f0ce;p=thirdparty%2Fsystemd.git

user-util: paranoia — add overflow check on ERANGE loop
---

diff --git a/src/basic/user-util.c b/src/basic/user-util.c
index b8d10669299..4cf4c5a3414 100644
--- a/src/basic/user-util.c
+++ b/src/basic/user-util.c
@@ -350,6 +350,9 @@ char* uid_to_name(uid_t uid) {
                         if (r != ERANGE)
                                 break;
 
+                        if (bufsize > LONG_MAX/2) /* overflow check */
+                                return NULL;
+
                         bufsize *= 2;
                 }
         }
@@ -391,6 +394,9 @@ char* gid_to_name(gid_t gid) {
                         if (r != ERANGE)
                                 break;
 
+                        if (bufsize > LONG_MAX/2) /* overflow check */
+                                return NULL;
+
                         bufsize *= 2;
                 }
         }