From: Oleg Nesterov <oleg@redhat.com>
To: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>, Kees Cook <kees@kernel.org>,
Kusaram Devineni <kusaram@devineni.in>,
Peter Zijlstra <peterz@infradead.org>,
Thomas Gleixner <tglx@kernel.org>, Will Drewry <wad@chromium.org>,
linux-kernel@vger.kernel.org
Subject: Re: [PATCH] signal: prevent evasion of SA_IMMUTABLE signals
Date: Wed, 29 Apr 2026 12:27:23 +0200 [thread overview]
Message-ID: <afHdC9-tFWQML46Z@redhat.com> (raw)
In-Reply-To: <afHBYTUA5XexTj-Q@redhat.com>
On 04/29, Oleg Nesterov wrote:
>
> static int __send_signal_locked(int sig, struct kernel_siginfo *info,
> struct task_struct *t, enum pid_type type, bool force)
> {
> + bool immutable = sa_immutable(t->sighand, sig);
OK, sashiko.dev raised the valid concern,
https://sashiko.dev/#/patchset/afHBYTUA5XexTj-Q%40redhat.com
If a signal action is marked SA_IMMUTABLE (for example, by forcing a fatal
SIGSEGV), and another thread repeatedly sends the same signal via kill(),
the legacy_queue() check is bypassed.
This check should be more strict. I'll send V2.
Oleg.
next prev parent reply other threads:[~2026-04-29 10:27 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2026-04-29 8:29 [PATCH] signal: prevent evasion of SA_IMMUTABLE signals Oleg Nesterov
2026-04-29 10:27 ` Oleg Nesterov [this message]
2026-05-02 18:28 ` kernel test robot
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