Re: [PATCH] nproc: Verify the cgroup path isn't truncated.
Collin Funk <[email protected]>
| Newsgroups | gmane.comp.lib.gnulib.bugs |
|---|---|
| Message-ID | <[email protected]> |
Collin Funk <[email protected]> writes: > - if ((fp = fopen (cpu_max_file, "r")) > + if (0 <= n && n < sizeof cpu_max_file > + && (fp = fopen (cpu_max_file, "r")) Oops. Coverity noticed that if the first expression is true, then FP won't be set to NULL or a newly opened file causing fclose to be called twice on the same file. I pushed the attached patch to fix that. Collin
0001-nproc-Don-t-call-fclose-twice-regr.-today.patch
(text/x-patch, 1.8 KB)
From 4bc1b5d165226c1a2c58f13fe1a5c94ccdaf26c8 Mon Sep 17 00:00:00 2001 Message-ID: <4bc1b5d165226c1a2c58f13fe1a5c94ccdaf26c8.1786939933.git.collin.funk1@gmail.com> From: Collin Funk <[email protected]> Date: Sun, 16 Aug 2026 21:08:23 -0700 Subject: [PATCH] nproc: Don't call fclose twice (regr. today). Problem found by Coverity (CID 1700233). * lib/nproc.c (get_cgroup2_cpu_quota): Set FP to NULL if fopen does not get called. --- ChangeLog | 7 +++++++ lib/nproc.c | 9 +++++---- 2 files changed, 12 insertions(+), 4 deletions(-) diff --git a/ChangeLog b/ChangeLog index 8a9ecfb0a5..89895173a0 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,10 @@ +2026-08-16 Collin Funk <[email protected]> + + nproc: Don't call fclose twice (regr. today). + Problem found by Coverity (CID 1700233). + * lib/nproc.c (get_cgroup2_cpu_quota): Set FP to NULL if fopen does not + get called. + 2026-08-16 Bruno Haible <[email protected]> tests: Avoid some test failures with the clang UBSAN. diff --git a/lib/nproc.c b/lib/nproc.c index e3dfeaa16d..821a913c3a 100644 --- a/lib/nproc.c +++ b/lib/nproc.c @@ -440,10 +440,11 @@ get_cgroup2_cpu_quota (void) int n = snprintf (cpu_max_file, sizeof (cpu_max_file), "%s%s/cpu.max", mount, cgroup); - if (0 <= n && n < sizeof cpu_max_file - && (fp = fopen (cpu_max_file, "r")) - && getline ("a_str, "a_size, fp) != -1 - && strncmp (quota_str, "max", 3) != 0) + if (n < 0 || sizeof cpu_max_file <= n) + fp = NULL; + else if ((fp = fopen (cpu_max_file, "r")) + && getline ("a_str, "a_size, fp) != -1 + && strncmp (quota_str, "max", 3) != 0) { long quota, period; if (sscanf (quota_str, "%ld %ld", "a, &period) == 2 && period) -- 2.55.0