[PATCH 4.14 v2 11/15] panic: Consolidate open-coded panic_on_warn checks

From: Eric Biggers <ebiggers@kernel.org>
To: stable@vger.kernel.org
Cc: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>,
	Kees Cook <keescook@chromium.org>, SeongJae Park <sj@kernel.org>,
	Seth Jenkins <sethjenkins@google.com>,
	Jann Horn <jannh@google.com>,
	"Eric W . Biederman" <ebiederm@xmission.com>,
	linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org,
	Marco Elver <elver@google.com>,
	Dmitry Vyukov <dvyukov@google.com>,
	Ingo Molnar <mingo@redhat.com>,
	Peter Zijlstra <peterz@infradead.org>,
	Juri Lelli <juri.lelli@redhat.com>,
	Vincent Guittot <vincent.guittot@linaro.org>,
	Dietmar Eggemann <dietmar.eggemann@arm.com>,
	Steven Rostedt <rostedt@goodmis.org>,
	Ben Segall <bsegall@google.com>, Mel Gorman <mgorman@suse.de>,
	Daniel Bristot de Oliveira <bristot@redhat.com>,
	Valentin Schneider <vschneid@redhat.com>,
	Andrey Ryabinin <ryabinin.a.a@gmail.com>,
	Alexander Potapenko <glider@google.com>,
	Andrey Konovalov <andreyknvl@gmail.com>,
	Vincenzo Frascino <vincenzo.frascino@arm.com>,
	Andrew Morton <akpm@linux-foundation.org>,
	David Gow <davidgow@google.com>,
	tangmeng <tangmeng@uniontech.com>,
	Shuah Khan <skhan@linuxfoundation.org>,
	Petr Mladek <pmladek@suse.com>,
	"Paul E. McKenney" <paulmck@kernel.org>,
	Sebastian Andrzej Siewior <bigeasy@linutronix.de>,
	"Guilherme G. Piccoli" <gpiccoli@igalia.com>,
	Tiezhu Yang <yangtiezhu@loongson.cn>,
	kasan-dev@googlegroups.com, linux-mm@kvack.org,
	Luis Chamberlain <mcgrof@kernel.org>
Subject: [PATCH 4.14 v2 11/15] panic: Consolidate open-coded panic_on_warn checks
Date: Thu,  2 Feb 2023 16:33:50 -0800	[thread overview]
Message-ID: <20230203003354.85691-12-ebiggers@kernel.org> (raw)
In-Reply-To: <20230203003354.85691-1-ebiggers@kernel.org>

From: Kees Cook <keescook@chromium.org>

commit 79cc1ba7badf9e7a12af99695a557e9ce27ee967 upstream.

Several run-time checkers (KASAN, UBSAN, KFENCE, KCSAN, sched) roll
their own warnings, and each check "panic_on_warn". Consolidate this
into a single function so that future instrumentation can be added in
a single location.

Cc: Marco Elver <elver@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Daniel Bristot de Oliveira <bristot@redhat.com>
Cc: Valentin Schneider <vschneid@redhat.com>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@gmail.com>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: David Gow <davidgow@google.com>
Cc: tangmeng <tangmeng@uniontech.com>
Cc: Jann Horn <jannh@google.com>
Cc: Shuah Khan <skhan@linuxfoundation.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: "Guilherme G. Piccoli" <gpiccoli@igalia.com>
Cc: Tiezhu Yang <yangtiezhu@loongson.cn>
Cc: kasan-dev@googlegroups.com
Cc: linux-mm@kvack.org
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Marco Elver <elver@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20221117234328.594699-4-keescook@chromium.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
---
 include/linux/kernel.h | 1 +
 kernel/panic.c         | 9 +++++++--
 kernel/sched/core.c    | 3 +--
 mm/kasan/report.c      | 3 +--
 4 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/include/linux/kernel.h b/include/linux/kernel.h
index 22b9146655958..a4ac278d02d0a 100644
--- a/include/linux/kernel.h
+++ b/include/linux/kernel.h
@@ -293,6 +293,7 @@ extern long (*panic_blink)(int state);
 __printf(1, 2)
 void panic(const char *fmt, ...) __noreturn __cold;
 void nmi_panic(struct pt_regs *regs, const char *msg);
+void check_panic_on_warn(const char *origin);
 extern void oops_enter(void);
 extern void oops_exit(void);
 void print_oops_end_marker(void);
diff --git a/kernel/panic.c b/kernel/panic.c
index bd7c3ea3bf1e6..8e3460e985904 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -122,6 +122,12 @@ void nmi_panic(struct pt_regs *regs, const char *msg)
 }
 EXPORT_SYMBOL(nmi_panic);
 
+void check_panic_on_warn(const char *origin)
+{
+	if (panic_on_warn)
+		panic("%s: panic_on_warn set ...\n", origin);
+}
+
 /**
  *	panic - halt the system
  *	@fmt: The text string to print
@@ -546,8 +552,7 @@ void __warn(const char *file, int line, void *caller, unsigned taint,
 	if (args)
 		vprintk(args->fmt, args->args);
 
-	if (panic_on_warn)
-		panic("panic_on_warn set ...\n");
+	check_panic_on_warn("kernel");
 
 	print_modules();
 
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 544a1cb66d90d..5dc66377864a9 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -3185,8 +3185,7 @@ static noinline void __schedule_bug(struct task_struct *prev)
 		print_ip_sym(preempt_disable_ip);
 		pr_cont("\n");
 	}
-	if (panic_on_warn)
-		panic("scheduling while atomic\n");
+	check_panic_on_warn("scheduling while atomic");
 
 	dump_stack();
 	add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index 6bcfb01ba0386..1c96c83f97751 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -172,8 +172,7 @@ static void kasan_end_report(unsigned long *flags)
 	pr_err("==================================================================\n");
 	add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE);
 	spin_unlock_irqrestore(&report_lock, *flags);
-	if (panic_on_warn)
-		panic("panic_on_warn set ...\n");
+	check_panic_on_warn("KASAN");
 	kasan_enable_current();
 }
 
-- 
2.39.1

