From e17ff7ab5115b80f0d2bd4989cd31889bd54fbb1 Mon Sep 17 00:00:00 2001 From: Lennart Poettering <lennart@poettering.net> Date: Wed, 9 Jul 2014 19:20:58 +0200 Subject: [PATCH] sysusers: don't allow user names longer than UT_NAMESIZE MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit As pointed out by Miloslav Trmač it might be a good idea to make sure that usernames stay with in the utmp-defined limits. (cherry picked from commit 932ad62b84165b0acf690ea34c4b8083657ae244) --- man/sysusers.d.xml | 2 +- src/sysusers/sysusers.c | 4 ++++ 2 files changed, 5 insertions(+), 1 deletion(-) diff --git a/man/sysusers.d.xml b/man/sysusers.d.xml index 549b3f6351..40f8715bc0 100644 --- a/man/sysusers.d.xml +++ b/man/sysusers.d.xml @@ -142,7 +142,7 @@ m authd input</programlisting> <title>Name</title> <para>The name field specifies the user or - group name. It should be be shorter than 256 + group name. It should be be shorter than 31 characters and avoid any non-ASCII characters, and not begin with a numeric character. It is strongly recommended to pick user and group diff --git a/src/sysusers/sysusers.c b/src/sysusers/sysusers.c index c0af69300a..f3ba8cf7b3 100644 --- a/src/sysusers/sysusers.c +++ b/src/sysusers/sysusers.c @@ -24,6 +24,7 @@ #include <grp.h> #include <shadow.h> #include <getopt.h> +#include <utmp.h> #include "util.h" #include "hashmap.h" @@ -1095,6 +1096,9 @@ static bool valid_user_group_name(const char *u) { if ((size_t) (i-u) > (size_t) sz) return false; + if ((size_t) (i-u) > UT_NAMESIZE - 1) + return false; + return true; }