[4.14,12/16] panic: Consolidate open-coded panic_on_warn checks

Commit Message

Eric Biggers Feb. 2, 2023, 5:44 a.m. UTC

From: Kees Cook <[e-mail]>

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 <[e-mail]>
Cc: Dmitry Vyukov <[e-mail]>
Cc: Ingo Molnar <[e-mail]>
Cc: Peter Zijlstra <[e-mail]>
Cc: Juri Lelli <[e-mail]>
Cc: Vincent Guittot <[e-mail]>
Cc: Dietmar Eggemann <[e-mail]>
Cc: Steven Rostedt <[e-mail]>
Cc: Ben Segall <[e-mail]>
Cc: Mel Gorman <[e-mail]>
Cc: Daniel Bristot de Oliveira <[e-mail]>
Cc: Valentin Schneider <[e-mail]>
Cc: Andrey Ryabinin <[e-mail]>
Cc: Alexander Potapenko <[e-mail]>
Cc: Andrey Konovalov <[e-mail]>
Cc: Vincenzo Frascino <[e-mail]>
Cc: Andrew Morton <[e-mail]>
Cc: David Gow <[e-mail]>
Cc: tangmeng <[e-mail]>
Cc: Jann Horn <[e-mail]>
Cc: Shuah Khan <[e-mail]>
Cc: Petr Mladek <[e-mail]>
Cc: "Paul E. McKenney" <[e-mail]>
Cc: Sebastian Andrzej Siewior <[e-mail]>
Cc: "Guilherme G. Piccoli" <[e-mail]>
Cc: Tiezhu Yang <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Reviewed-by: Luis Chamberlain <[e-mail]>
Signed-off-by: Kees Cook <[e-mail]>
Reviewed-by: Marco Elver <[e-mail]>
Reviewed-by: Andrey Konovalov <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Eric Biggers <[e-mail]>
---
 include/linux/kernel.h | 1 +
 kernel/panic.c         | 9 +++++++--
 kernel/sched/core.c    | 3 +--
 mm/kasan/report.c      | 4 ++--
 4 files changed, 11 insertions(+), 6 deletions(-)

Patch

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 5b421f8433488..4dc577d7e7494 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -172,8 +172,8 @@  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 && !test_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags))
-		panic("panic_on_warn set ...\n");
+	if (!test_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags))
+		check_panic_on_warn("KASAN");
 	kasan_enable_current();
 }