Re: [PATCH] Introduce the pkill_on_warn boot parameter
From: Al Viro <viro@zeniv.linux.org.uk>
Date: 2021-10-02 18:22:14
Also in:
linux-hardening, lkml
On Wed, Sep 29, 2021 at 09:58:23PM +0300, Alexander Popov wrote:
quoted hunk ↗ jump to hunk
--- a/kernel/panic.c +++ b/kernel/panic.c@@ -53,6 +53,7 @@ static int pause_on_oops_flag; static DEFINE_SPINLOCK(pause_on_oops_lock); bool crash_kexec_post_notifiers; int panic_on_warn __read_mostly; +int pkill_on_warn __read_mostly; unsigned long panic_on_taint; bool panic_on_taint_nousertaint = false;@@ -610,6 +611,9 @@ void __warn(const char *file, int line, void *caller, unsigned taint, print_oops_end_marker(); + if (pkill_on_warn && system_state >= SYSTEM_RUNNING) + do_group_exit(SIGKILL); +
Wait a sec... do_group_exit() is very much not locking-neutral. Aren't you introducing a bunch of potential deadlocks by adding that?