lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Thu, 21 Apr 2022 00:39:51 +0000
From:   Alexander Lobakin <>
To:     Alexei Starovoitov <>,
        Daniel Borkmann <>,
        Andrii Nakryiko <>
Cc:     Alexander Lobakin <>,
        Maciej Fijalkowski <>,
        Song Liu <>,
        Kumar Kartikeya Dwivedi <>,,,
Subject: [PATCH v2 bpf 10/11] samples/bpf: fix -Wsequence-point

In some libc implementations, CPU_SET() may utilize its first
argument several times. When combined with a post-increment,
it leads to:

samples/bpf/test_lru_dist.c:233:36: warning: operation on 'next_to_try' may be undefined [-Wsequence-point]
  233 |                 CPU_SET(next_to_try++, &cpuset);
      |                                    ^

Macros must always define local copies of arguments to avoid
reusing, but since several libc versions already and still have
that, split the sentence into two standalone operations to fix

Fixes: 5db58faf989f ("bpf: Add tests for the LRU bpf_htab")
Acked-by: Song Liu <>
Signed-off-by: Alexander Lobakin <>
 samples/bpf/test_lru_dist.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/samples/bpf/test_lru_dist.c b/samples/bpf/test_lru_dist.c
index 75e877853596..d09ccd5370e8 100644
--- a/samples/bpf/test_lru_dist.c
+++ b/samples/bpf/test_lru_dist.c
@@ -230,7 +230,8 @@ static int sched_next_online(int pid, int next_to_try)

 	while (next_to_try < nr_cpus) {
-		CPU_SET(next_to_try++, &cpuset);
+		CPU_SET(next_to_try, &cpuset);
+		next_to_try++;
 		if (!sched_setaffinity(pid, sizeof(cpuset), &cpuset))

Powered by blists - more mailing lists