Commit 79cc1ba7 authored by Kees Cook's avatar Kees Cook
Browse files

panic: Consolidate open-coded panic_on_warn checks 



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: default avatarLuis Chamberlain <mcgrof@kernel.org>
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Reviewed-by: default avatarMarco Elver <elver@google.com>
Reviewed-by: default avatarAndrey Konovalov <andreyknvl@gmail.com>
Link: https://lore.kernel.org/r/20221117234328.594699-4-keescook@chromium.org
parent de92f657

include/linux/panic.h

+1 −0
Original line number Diff line number Diff line
@@ -11,6 +11,7 @@ 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);

extern bool oops_may_print(void);

kernel/kcsan/report.c

+1 −2
Original line number Diff line number Diff line
@@ -492,8 +492,7 @@ static void print_report(enum kcsan_value_change value_change, 
	dump_stack_print_info(KERN_DEFAULT);

	pr_err("==================================================================\n");



	if (panic_on_warn)

		panic("panic_on_warn set ...\n");

	check_panic_on_warn("KCSAN");

}



static void release_report(unsigned long *flags, struct other_info *other_info)

kernel/panic.c

+7 −2
Original line number Diff line number Diff line
@@ -201,6 +201,12 @@ static void panic_print_sys_info(bool console_flush) 
		ftrace_dump(DUMP_ALL);

}



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
@@ -619,8 +625,7 @@ void __warn(const char *file, int line, void *caller, unsigned taint, 
	if (regs)

		show_regs(regs);



	if (panic_on_warn)

		panic("panic_on_warn set ...\n");

	check_panic_on_warn("kernel");



	if (!regs)

		dump_stack();

kernel/sched/core.c

+1 −2
Original line number Diff line number Diff line
@@ -5729,8 +5729,7 @@ static noinline void __schedule_bug(struct task_struct *prev) 
		pr_err("Preemption disabled at:");

		print_ip_sym(KERN_ERR, preempt_disable_ip);

	}

	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);

lib/ubsan.c

+1 −2
Original line number Diff line number Diff line
@@ -154,8 +154,7 @@ static void ubsan_epilogue(void) 


	current->in_ubsan--;



	if (panic_on_warn)

		panic("panic_on_warn set ...\n");

	check_panic_on_warn("UBSAN");

}



void __ubsan_handle_divrem_overflow(void *_data, void *lhs, void *rhs)