diff options
Diffstat (limited to 'mm/kasan/report.c')
| -rw-r--r-- | mm/kasan/report.c | 61 |
1 files changed, 47 insertions, 14 deletions
diff --git a/mm/kasan/report.c b/mm/kasan/report.c index 7afa4feb03e1..8357e1a33699 100644 --- a/mm/kasan/report.c +++ b/mm/kasan/report.c @@ -10,6 +10,7 @@ */ #include <kunit/test.h> +#include <kunit/visibility.h> #include <linux/bitops.h> #include <linux/ftrace.h> #include <linux/init.h> @@ -132,20 +133,20 @@ static bool report_enabled(void) return !test_and_set_bit(KASAN_BIT_REPORTED, &kasan_flags); } -#if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) || IS_ENABLED(CONFIG_KASAN_MODULE_TEST) +#if IS_ENABLED(CONFIG_KASAN_KUNIT_TEST) -bool kasan_save_enable_multi_shot(void) +VISIBLE_IF_KUNIT bool kasan_save_enable_multi_shot(void) { return test_and_set_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags); } -EXPORT_SYMBOL_GPL(kasan_save_enable_multi_shot); +EXPORT_SYMBOL_IF_KUNIT(kasan_save_enable_multi_shot); -void kasan_restore_multi_shot(bool enabled) +VISIBLE_IF_KUNIT void kasan_restore_multi_shot(bool enabled) { if (!enabled) clear_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags); } -EXPORT_SYMBOL_GPL(kasan_restore_multi_shot); +EXPORT_SYMBOL_IF_KUNIT(kasan_restore_multi_shot); #endif @@ -157,17 +158,17 @@ EXPORT_SYMBOL_GPL(kasan_restore_multi_shot); */ static bool kasan_kunit_executing; -void kasan_kunit_test_suite_start(void) +VISIBLE_IF_KUNIT void kasan_kunit_test_suite_start(void) { WRITE_ONCE(kasan_kunit_executing, true); } -EXPORT_SYMBOL_GPL(kasan_kunit_test_suite_start); +EXPORT_SYMBOL_IF_KUNIT(kasan_kunit_test_suite_start); -void kasan_kunit_test_suite_end(void) +VISIBLE_IF_KUNIT void kasan_kunit_test_suite_end(void) { WRITE_ONCE(kasan_kunit_executing, false); } -EXPORT_SYMBOL_GPL(kasan_kunit_test_suite_end); +EXPORT_SYMBOL_IF_KUNIT(kasan_kunit_test_suite_end); static bool kasan_kunit_test_suite_executing(void) { @@ -200,7 +201,7 @@ static inline void fail_non_kasan_kunit_test(void) { } #endif /* CONFIG_KUNIT */ -static DEFINE_SPINLOCK(report_lock); +static DEFINE_RAW_SPINLOCK(report_lock); static void start_report(unsigned long *flags, bool sync) { @@ -211,7 +212,7 @@ static void start_report(unsigned long *flags, bool sync) lockdep_off(); /* Make sure we don't end up in loop. */ report_suppress_start(); - spin_lock_irqsave(&report_lock, *flags); + raw_spin_lock_irqsave(&report_lock, *flags); pr_err("==================================================================\n"); } @@ -221,7 +222,7 @@ static void end_report(unsigned long *flags, const void *addr, bool is_write) trace_error_report_end(ERROR_DETECTOR_KASAN, (unsigned long)addr); pr_err("==================================================================\n"); - spin_unlock_irqrestore(&report_lock, *flags); + raw_spin_unlock_irqrestore(&report_lock, *flags); if (!test_bit(KASAN_BIT_MULTI_SHOT, &kasan_flags)) check_panic_on_warn("KASAN"); switch (kasan_arg_fault) { @@ -267,7 +268,7 @@ static void print_track(struct kasan_track *track, const char *prefix) u64 ts_nsec = track->timestamp; unsigned long rem_usec; - ts_nsec <<= 3; + ts_nsec <<= 9; rem_usec = do_div(ts_nsec, NSEC_PER_SEC) / 1000; pr_err("%s by task %u on cpu %d at %lu.%06lus:\n", @@ -369,6 +370,36 @@ static inline bool init_task_stack_addr(const void *addr) sizeof(init_thread_union.stack)); } +/* + * This function is invoked with report_lock (a raw_spinlock) held. A + * PREEMPT_RT kernel cannot call find_vm_area() as it will acquire a sleeping + * rt_spinlock. + * + * For !RT kernel, the PROVE_RAW_LOCK_NESTING config option will print a + * lockdep warning for this raw_spinlock -> spinlock dependency. This config + * option is enabled by default to ensure better test coverage to expose this + * kind of RT kernel problem. This lockdep splat, however, can be suppressed + * by using DEFINE_WAIT_OVERRIDE_MAP() if it serves a useful purpose and the + * invalid PREEMPT_RT case has been taken care of. + */ +static inline struct vm_struct *kasan_find_vm_area(void *addr) +{ + static DEFINE_WAIT_OVERRIDE_MAP(vmalloc_map, LD_WAIT_SLEEP); + struct vm_struct *va; + + if (IS_ENABLED(CONFIG_PREEMPT_RT)) + return NULL; + + /* + * Suppress lockdep warning and fetch vmalloc area of the + * offending address. + */ + lock_map_acquire_try(&vmalloc_map); + va = find_vm_area(addr); + lock_map_release(&vmalloc_map); + return va; +} + static void print_address_description(void *addr, u8 tag, struct kasan_report_info *info) { @@ -398,7 +429,7 @@ static void print_address_description(void *addr, u8 tag, } if (is_vmalloc_addr(addr)) { - struct vm_struct *va = find_vm_area(addr); + struct vm_struct *va = kasan_find_vm_area(addr); if (va) { pr_err("The buggy address belongs to the virtual mapping at\n" @@ -408,6 +439,8 @@ static void print_address_description(void *addr, u8 tag, pr_err("\n"); page = vmalloc_to_page(addr); + } else { + pr_err("The buggy address %px belongs to a vmalloc virtual mapping\n", addr); } } |