From: Lennart Poettering <lennart@poettering.net>
Date: Mon, 8 Mar 2021 20:44:39 +0000 (+0100)
Subject: basic: tighten two filename length checks
X-Git-Tag: v248-rc3~24^2~6
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8ca94009f826315002d62364efe0c880a13ba8c5;p=thirdparty%2Fsystemd.git

basic: tighten two filename length checks

This fixes two checks where we compare string sizes when validating with
FILENAME_MAX. In both cases the check apparently wants to check if the
name fits in a filename, but that's not actually what FILENAME_MAX can
be used for, as it — in contrast to what the name suggests — actually
encodes the maximum length of a path.

In both cases the stricter change doesn't actually change much, but the
use of FILENAME_MAX is still misleading and typically wrong.
---

diff --git a/src/basic/cgroup-util.c b/src/basic/cgroup-util.c
index 0ecb8d944e9..7372b06024a 100644
--- a/src/basic/cgroup-util.c
+++ b/src/basic/cgroup-util.c
@@ -1567,7 +1567,7 @@ bool cg_controller_is_valid(const char *p) {
                 if (!strchr(CONTROLLER_VALID, *t))
                         return false;
 
-        if (t - p > FILENAME_MAX)
+        if (t - p > NAME_MAX)
                 return false;
 
         return true;
diff --git a/src/basic/user-util.c b/src/basic/user-util.c
index 1fad342cef3..0ea4e409fac 100644
--- a/src/basic/user-util.c
+++ b/src/basic/user-util.c
@@ -836,7 +836,7 @@ bool valid_user_group_name(const char *u, ValidUserFlags flags) {
 
                 if (l > (size_t) sz)
                         return false;
-                if (l > FILENAME_MAX)
+                if (l > NAME_MAX) /* must fit in a filename */
                         return false;
                 if (l > UT_NAMESIZE - 1)
                         return false;