panic: Consolidate open-coded panic_on_warn checks

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>
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/include/linux/panic.h b/include/linux/panic.h
index e71161d..8eb5897 100644 (file)
--- a/include/linux/panic.h
+++ b/include/linux/panic.h
@@ -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);

diff --git a/kernel/kcsan/report.c b/kernel/kcsan/report.c
index 2113792..b88d5d5 100644 (file)
--- a/kernel/kcsan/report.c
+++ b/kernel/kcsan/report.c
@@ -432,8 +432,7 @@ 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)

diff --git a/kernel/panic.c b/kernel/panic.c
index 0b56031..bf03249 100644 (file)
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -193,6 +193,12 @@ static void panic_print_sys_info(void)
                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
@@ -628,8 +634,7 @@ 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();

diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 2bd5e23..c1458fa 100644 (file)
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -5560,8 +5560,7 @@ 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);

diff --git a/lib/ubsan.c b/lib/ubsan.c
index 36bd75e..60c7099 100644 (file)
--- a/lib/ubsan.c
+++ b/lib/ubsan.c
@@ -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)

diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index bf17704..887af87 100644 (file)
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -117,8 +117,8 @@ static void end_report(unsigned long *flags, unsigned long addr)
        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");
        if (kasan_arg_fault == KASAN_ARG_FAULT_PANIC)
                panic("kasan.fault=panic set ...\n");
        kasan_enable_current();

diff --git a/mm/kfence/report.c b/mm/kfence/report.c
index 37e140e..cbd9456 100644 (file)
--- a/mm/kfence/report.c
+++ b/mm/kfence/report.c
@@ -267,8 +267,7 @@ void kfence_report_error(unsigned long address, bool is_write, struct pt_regs *r
 
        lockdep_on();
 
-       if (panic_on_warn)
-               panic("panic_on_warn set ...\n");
+       check_panic_on_warn("KFENCE");
 
        /* We encountered a memory safety error, taint the kernel! */
        add_taint(TAINT_BAD_PAGE, LOCKDEP_STILL_OK);