From 79cc1ba7badf9e7a12af99695a557e9ce27ee967 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Thu, 17 Nov 2022 15:43:24 -0800 Subject: [PATCH] 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 Cc: Dmitry Vyukov Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Juri Lelli Cc: Vincent Guittot Cc: Dietmar Eggemann Cc: Steven Rostedt Cc: Ben Segall Cc: Mel Gorman Cc: Daniel Bristot de Oliveira Cc: Valentin Schneider Cc: Andrey Ryabinin Cc: Alexander Potapenko Cc: Andrey Konovalov Cc: Vincenzo Frascino Cc: Andrew Morton Cc: David Gow Cc: tangmeng Cc: Jann Horn Cc: Shuah Khan Cc: Petr Mladek Cc: "Paul E. McKenney" Cc: Sebastian Andrzej Siewior Cc: "Guilherme G. Piccoli" Cc: Tiezhu Yang Cc: kasan-dev@googlegroups.com Cc: linux-mm@kvack.org Reviewed-by: Luis Chamberlain Signed-off-by: Kees Cook Reviewed-by: Marco Elver Reviewed-by: Andrey Konovalov Link: https://lore.kernel.org/r/20221117234328.594699-4-keescook@chromium.org --- include/linux/panic.h | 1 + kernel/kcsan/report.c | 3 +-- kernel/panic.c | 9 +++++++-- kernel/sched/core.c | 3 +-- lib/ubsan.c | 3 +-- mm/kasan/report.c | 4 ++-- mm/kfence/report.c | 3 +-- 7 files changed, 14 insertions(+), 12 deletions(-) diff --git a/include/linux/panic.h b/include/linux/panic.h index c7759b3..979b776 100644 --- 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 6779440..e95ce7d 100644 --- a/kernel/kcsan/report.c +++ b/kernel/kcsan/report.c @@ -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) diff --git a/kernel/panic.c b/kernel/panic.c index d843d03..cfa3543 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -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(); diff --git a/kernel/sched/core.c b/kernel/sched/core.c index 5800b06..285ef88 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -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); diff --git a/lib/ubsan.c b/lib/ubsan.c index 36bd75e..60c7099 100644 --- 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 df36020..cc98dfd 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -164,8 +164,8 @@ static void end_report(unsigned long *flags, void *addr) (unsigned long)addr); pr_err("==================================================================\n"); 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"); add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); diff --git a/mm/kfence/report.c b/mm/kfence/report.c index 7e49685..110c27c 100644 --- a/mm/kfence/report.c +++ b/mm/kfence/report.c @@ -268,8 +268,7 @@ 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); -- 2.7.4