Re: [PATCH] nproc: Verify the cgroup path isn't truncated.

[Pádraig Brady]

On 16/08/2026 07:50, Collin Funk wrote:

I don't think it is actually possible for this case to happen, but
checking it does no harm.

Lasse Collin mentioned it to me while we were discussing some cgroup
stuff a while ago.

diff --git a/lib/nproc.c b/lib/nproc.c
index ef86975fb1..e3dfeaa16d 100644
--- a/lib/nproc.c
+++ b/lib/nproc.c
@@ -437,10 +437,11 @@ get_cgroup2_cpu_quota (void)
           is not enabled for that part of the hierarchy.  */

char cpu_max_file[PATH_MAX];

-      snprintf (cpu_max_file, sizeof (cpu_max_file),
-                "%s%s/cpu.max", mount, cgroup);
+      int n = snprintf (cpu_max_file, sizeof (cpu_max_file),
+                        "%s%s/cpu.max", mount, cgroup);

- if ((fp = fopen (cpu_max_file, "r"))

+      if (0 <= n && n < sizeof cpu_max_file
+          && (fp = fopen (cpu_max_file, "r"))
            && getline (&quota_str, &quota_size, fp) != -1
            && strncmp (quota_str, "max", 3) != 0)
          {

LGTM.

cheers,
Padraig