Commit 1d2252fa authored Apr 06, 2020 by Kees Cook Committed by Linus Torvalds Apr 07, 2020

kasan: unset panic_on_warn before calling panic()

As done in the full WARN() handler, panic_on_warn needs to be cleared
before calling panic() to avoid recursive panics.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Elena Petrova <lenaptr@google.com>
Cc: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
Link: http://lkml.kernel.org/r/20200227193516.32566-6-keescook@chromium.org

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

parent 1d28c8d6

mm/kasan/report.c

+9 −1

Original line number	Diff line number	Diff line
		@@ -92,8 +92,16 @@ static void 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)
		if (panic_on_warn) {
		/*
		* This thread may hit another WARN() in the panic path.
		* Resetting this prevents additional WARN() from panicking the
		* system on this thread. Other threads are blocked by the
		* panic_mutex in panic().
		*/
		panic_on_warn = 0;
		panic("panic_on_warn set ...\n");
		}
		kasan_enable_current();
		}

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