From: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Subject: kasan: split out print_report from __kasan_report Split out the part of __kasan_report() that prints things into print_report(). One of the subsequent patches makes another error handler use print_report() as well. Includes lower-level changes: - Allow addr_has_metadata() accepting a tagged address. - Drop the const qualifier from the fields of kasan_access_info to avoid excessive type casts. - Change the type of the address argument of __kasan_report() and end_report() to void * to reduce the number of type casts. Link: https://lkml.kernel.org/r/9be3ed99dd24b9c4e1c4a848b69a0c6ecefd845e.1646237226.git.andreyknvl@xxxxxxxxxx Signed-off-by: Andrey Konovalov <andreyknvl@xxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Andrey Ryabinin <ryabinin.a.a@xxxxxxxxx> Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx> Cc: Marco Elver <elver@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/kasan/kasan.h | 7 +++-- mm/kasan/report.c | 58 +++++++++++++++++++++++--------------------- 2 files changed, 35 insertions(+), 30 deletions(-) --- a/mm/kasan/kasan.h~kasan-split-out-print_report-from-__kasan_report +++ a/mm/kasan/kasan.h @@ -128,8 +128,8 @@ static inline bool kasan_sync_fault_poss #define META_ROWS_AROUND_ADDR 2 struct kasan_access_info { - const void *access_addr; - const void *first_bad_addr; + void *access_addr; + void *first_bad_addr; size_t access_size; bool is_write; unsigned long ip; @@ -239,7 +239,8 @@ static inline const void *kasan_shadow_t static inline bool addr_has_metadata(const void *addr) { - return (addr >= kasan_shadow_to_mem((void *)KASAN_SHADOW_START)); + return (kasan_reset_tag(addr) >= + kasan_shadow_to_mem((void *)KASAN_SHADOW_START)); } /** --- a/mm/kasan/report.c~kasan-split-out-print_report-from-__kasan_report +++ a/mm/kasan/report.c @@ -139,10 +139,11 @@ static void start_report(unsigned long * pr_err("==================================================================\n"); } -static void end_report(unsigned long *flags, unsigned long addr) +static void end_report(unsigned long *flags, void *addr) { if (addr) - trace_error_report_end(ERROR_DETECTOR_KASAN, addr); + trace_error_report_end(ERROR_DETECTOR_KASAN, + (unsigned long)addr); pr_err("==================================================================\n"); add_taint(TAINT_BAD_PAGE, LOCKDEP_NOW_UNRELIABLE); spin_unlock_irqrestore(&report_lock, *flags); @@ -398,7 +399,7 @@ void kasan_report_invalid_free(void *obj pr_err("\n"); print_address_description(object, tag); print_memory_metadata(object); - end_report(&flags, (unsigned long)object); + end_report(&flags, object); } #ifdef CONFIG_KASAN_HW_TAGS @@ -411,44 +412,47 @@ void kasan_report_async(void) pr_err("Asynchronous mode enabled: no access details available\n"); pr_err("\n"); dump_stack_lvl(KERN_ERR); - end_report(&flags, 0); + end_report(&flags, NULL); } #endif /* CONFIG_KASAN_HW_TAGS */ -static void __kasan_report(unsigned long addr, size_t size, bool is_write, +static void print_report(struct kasan_access_info *info) +{ + void *tagged_addr = info->access_addr; + void *untagged_addr = kasan_reset_tag(tagged_addr); + u8 tag = get_tag(tagged_addr); + + print_error_description(info); + if (addr_has_metadata(untagged_addr)) + kasan_print_tags(tag, info->first_bad_addr); + pr_err("\n"); + + if (addr_has_metadata(untagged_addr)) { + print_address_description(untagged_addr, tag); + print_memory_metadata(info->first_bad_addr); + } else { + dump_stack_lvl(KERN_ERR); + } +} + +static void __kasan_report(void *addr, size_t size, bool is_write, unsigned long ip) { struct kasan_access_info info; - void *tagged_addr; - void *untagged_addr; unsigned long flags; start_report(&flags, true); - tagged_addr = (void *)addr; - untagged_addr = kasan_reset_tag(tagged_addr); - - info.access_addr = tagged_addr; - if (addr_has_metadata(untagged_addr)) - info.first_bad_addr = - kasan_find_first_bad_addr(tagged_addr, size); + info.access_addr = addr; + if (addr_has_metadata(addr)) + info.first_bad_addr = kasan_find_first_bad_addr(addr, size); else - info.first_bad_addr = untagged_addr; + info.first_bad_addr = addr; info.access_size = size; info.is_write = is_write; info.ip = ip; - print_error_description(&info); - if (addr_has_metadata(untagged_addr)) - kasan_print_tags(get_tag(tagged_addr), info.first_bad_addr); - pr_err("\n"); - - if (addr_has_metadata(untagged_addr)) { - print_address_description(untagged_addr, get_tag(tagged_addr)); - print_memory_metadata(info.first_bad_addr); - } else { - dump_stack_lvl(KERN_ERR); - } + print_report(&info); end_report(&flags, addr); } @@ -460,7 +464,7 @@ bool kasan_report(unsigned long addr, si bool ret = false; if (likely(report_enabled())) { - __kasan_report(addr, size, is_write, ip); + __kasan_report((void *)addr, size, is_write, ip); ret = true; } _
