From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 188A9C433E0 for ; Tue, 22 Dec 2020 20:00:59 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id B521621D1B for ; Tue, 22 Dec 2020 20:00:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B521621D1B Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 47F8F6B00B7; Tue, 22 Dec 2020 15:00:53 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 33D096B00B8; Tue, 22 Dec 2020 15:00:53 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 1DBF16B00B9; Tue, 22 Dec 2020 15:00:53 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0105.hostedemail.com [216.40.44.105]) by kanga.kvack.org (Postfix) with ESMTP id EF5776B00B7 for ; Tue, 22 Dec 2020 15:00:52 -0500 (EST) Received: from smtpin05.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id B943B1EF1 for ; Tue, 22 Dec 2020 20:00:52 +0000 (UTC) X-FDA: 77621986344.05.maid66_1006f8727462 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin05.hostedemail.com (Postfix) with ESMTP id 98C8318027FBA for ; Tue, 22 Dec 2020 20:00:52 +0000 (UTC) X-HE-Tag: maid66_1006f8727462 X-Filterd-Recvd-Size: 13237 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf09.hostedemail.com (Postfix) with ESMTP for ; Tue, 22 Dec 2020 20:00:51 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 5519923139; Tue, 22 Dec 2020 20:00:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1608667251; bh=756GrEw9riVx6R5mXVZ+zUzRgjk0NVBevAxEpXN7LqI=; h=Date:From:To:Subject:In-Reply-To:From; b=KXpKMuh6Egev5mUViKglX1v2H1ffDw91eWTiBk0elzYHpgByDXUZCexw7/EX6x934 rV5OdPMDrO8EUO+HtSgrVsacbOVb2eerUiiDpJyMSteB6ZPSo5gBIb6e5RFINDudlo IUKzPAbACzOkM+QBUgOUQwJidv7HScBDbD7CieAc= Date: Tue, 22 Dec 2020 12:00:49 -0800 From: Andrew Morton To: akpm@linux-foundation.org, andreyknvl@google.com, aryabinin@virtuozzo.com, Branislav.Rankov@arm.com, catalin.marinas@arm.com, dvyukov@google.com, elver@google.com, eugenis@google.com, glider@google.com, gor@linux.ibm.com, kevin.brodsky@arm.com, linux-mm@kvack.org, mm-commits@vger.kernel.org, torvalds@linux-foundation.org, vincenzo.frascino@arm.com, will.deacon@arm.com Subject: [patch 13/60] kasan: decode stack frame only with KASAN_STACK_ENABLE Message-ID: <20201222200049.DgifxXrKv%akpm@linux-foundation.org> In-Reply-To: <20201222115844.d30aaef7df6f5b120d3e0c3d@linux-foundation.org> User-Agent: s-nail v14.8.16 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: From: Andrey Konovalov Subject: kasan: decode stack frame only with KASAN_STACK_ENABLE Decoding routines aren't needed when CONFIG_KASAN_STACK_ENABLE is not enabled. Currently only generic KASAN mode implements stack error reporting. No functional changes for software modes. Link: https://lkml.kernel.org/r/05a24db36f5ec876af876a299bbea98c29468ebd.1606161801.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Signed-off-by: Vincenzo Frascino Reviewed-by: Marco Elver Reviewed-by: Alexander Potapenko Tested-by: Vincenzo Frascino Cc: Andrey Ryabinin Cc: Branislav Rankov Cc: Catalin Marinas Cc: Dmitry Vyukov Cc: Evgenii Stepanov Cc: Kevin Brodsky Cc: Vasily Gorbik Cc: Will Deacon Signed-off-by: Andrew Morton --- mm/kasan/kasan.h | 6 + mm/kasan/report.c | 162 ------------------------------------ mm/kasan/report_generic.c | 162 ++++++++++++++++++++++++++++++++++++ 3 files changed, 168 insertions(+), 162 deletions(-) --- a/mm/kasan/kasan.h~kasan-decode-stack-frame-only-with-kasan_stack_enable +++ a/mm/kasan/kasan.h @@ -171,6 +171,12 @@ bool check_invalid_free(void *addr); void *find_first_bad_addr(void *addr, size_t size); const char *get_bug_type(struct kasan_access_info *info); +#if defined(CONFIG_KASAN_GENERIC) && CONFIG_KASAN_STACK +void print_address_stack_frame(const void *addr); +#else +static inline void print_address_stack_frame(const void *addr) { } +#endif + bool kasan_report(unsigned long addr, size_t size, bool is_write, unsigned long ip); void kasan_report_invalid_free(void *object, unsigned long ip); --- a/mm/kasan/report.c~kasan-decode-stack-frame-only-with-kasan_stack_enable +++ a/mm/kasan/report.c @@ -211,168 +211,6 @@ static inline bool init_task_stack_addr( sizeof(init_thread_union.stack)); } -static bool __must_check tokenize_frame_descr(const char **frame_descr, - char *token, size_t max_tok_len, - unsigned long *value) -{ - const char *sep = strchr(*frame_descr, ' '); - - if (sep == NULL) - sep = *frame_descr + strlen(*frame_descr); - - if (token != NULL) { - const size_t tok_len = sep - *frame_descr; - - if (tok_len + 1 > max_tok_len) { - pr_err("KASAN internal error: frame description too long: %s\n", - *frame_descr); - return false; - } - - /* Copy token (+ 1 byte for '\0'). */ - strlcpy(token, *frame_descr, tok_len + 1); - } - - /* Advance frame_descr past separator. */ - *frame_descr = sep + 1; - - if (value != NULL && kstrtoul(token, 10, value)) { - pr_err("KASAN internal error: not a valid number: %s\n", token); - return false; - } - - return true; -} - -static void print_decoded_frame_descr(const char *frame_descr) -{ - /* - * We need to parse the following string: - * "n alloc_1 alloc_2 ... alloc_n" - * where alloc_i looks like - * "offset size len name" - * or "offset size len name:line". - */ - - char token[64]; - unsigned long num_objects; - - if (!tokenize_frame_descr(&frame_descr, token, sizeof(token), - &num_objects)) - return; - - pr_err("\n"); - pr_err("this frame has %lu %s:\n", num_objects, - num_objects == 1 ? "object" : "objects"); - - while (num_objects--) { - unsigned long offset; - unsigned long size; - - /* access offset */ - if (!tokenize_frame_descr(&frame_descr, token, sizeof(token), - &offset)) - return; - /* access size */ - if (!tokenize_frame_descr(&frame_descr, token, sizeof(token), - &size)) - return; - /* name length (unused) */ - if (!tokenize_frame_descr(&frame_descr, NULL, 0, NULL)) - return; - /* object name */ - if (!tokenize_frame_descr(&frame_descr, token, sizeof(token), - NULL)) - return; - - /* Strip line number; without filename it's not very helpful. */ - strreplace(token, ':', '\0'); - - /* Finally, print object information. */ - pr_err(" [%lu, %lu) '%s'", offset, offset + size, token); - } -} - -static bool __must_check get_address_stack_frame_info(const void *addr, - unsigned long *offset, - const char **frame_descr, - const void **frame_pc) -{ - unsigned long aligned_addr; - unsigned long mem_ptr; - const u8 *shadow_bottom; - const u8 *shadow_ptr; - const unsigned long *frame; - - BUILD_BUG_ON(IS_ENABLED(CONFIG_STACK_GROWSUP)); - - /* - * NOTE: We currently only support printing frame information for - * accesses to the task's own stack. - */ - if (!object_is_on_stack(addr)) - return false; - - aligned_addr = round_down((unsigned long)addr, sizeof(long)); - mem_ptr = round_down(aligned_addr, KASAN_GRANULE_SIZE); - shadow_ptr = kasan_mem_to_shadow((void *)aligned_addr); - shadow_bottom = kasan_mem_to_shadow(end_of_stack(current)); - - while (shadow_ptr >= shadow_bottom && *shadow_ptr != KASAN_STACK_LEFT) { - shadow_ptr--; - mem_ptr -= KASAN_GRANULE_SIZE; - } - - while (shadow_ptr >= shadow_bottom && *shadow_ptr == KASAN_STACK_LEFT) { - shadow_ptr--; - mem_ptr -= KASAN_GRANULE_SIZE; - } - - if (shadow_ptr < shadow_bottom) - return false; - - frame = (const unsigned long *)(mem_ptr + KASAN_GRANULE_SIZE); - if (frame[0] != KASAN_CURRENT_STACK_FRAME_MAGIC) { - pr_err("KASAN internal error: frame info validation failed; invalid marker: %lu\n", - frame[0]); - return false; - } - - *offset = (unsigned long)addr - (unsigned long)frame; - *frame_descr = (const char *)frame[1]; - *frame_pc = (void *)frame[2]; - - return true; -} - -static void print_address_stack_frame(const void *addr) -{ - unsigned long offset; - const char *frame_descr; - const void *frame_pc; - - if (IS_ENABLED(CONFIG_KASAN_SW_TAGS)) - return; - - if (!get_address_stack_frame_info(addr, &offset, &frame_descr, - &frame_pc)) - return; - - /* - * get_address_stack_frame_info only returns true if the given addr is - * on the current task's stack. - */ - pr_err("\n"); - pr_err("addr %px is located in stack of task %s/%d at offset %lu in frame:\n", - addr, current->comm, task_pid_nr(current), offset); - pr_err(" %pS\n", frame_pc); - - if (!frame_descr) - return; - - print_decoded_frame_descr(frame_descr); -} - static void print_address_description(void *addr, u8 tag) { struct page *page = kasan_addr_to_page(addr); --- a/mm/kasan/report_generic.c~kasan-decode-stack-frame-only-with-kasan_stack_enable +++ a/mm/kasan/report_generic.c @@ -16,6 +16,7 @@ #include #include #include +#include #include #include #include @@ -122,6 +123,167 @@ const char *get_bug_type(struct kasan_ac return get_wild_bug_type(info); } +#if CONFIG_KASAN_STACK +static bool __must_check tokenize_frame_descr(const char **frame_descr, + char *token, size_t max_tok_len, + unsigned long *value) +{ + const char *sep = strchr(*frame_descr, ' '); + + if (sep == NULL) + sep = *frame_descr + strlen(*frame_descr); + + if (token != NULL) { + const size_t tok_len = sep - *frame_descr; + + if (tok_len + 1 > max_tok_len) { + pr_err("KASAN internal error: frame description too long: %s\n", + *frame_descr); + return false; + } + + /* Copy token (+ 1 byte for '\0'). */ + strlcpy(token, *frame_descr, tok_len + 1); + } + + /* Advance frame_descr past separator. */ + *frame_descr = sep + 1; + + if (value != NULL && kstrtoul(token, 10, value)) { + pr_err("KASAN internal error: not a valid number: %s\n", token); + return false; + } + + return true; +} + +static void print_decoded_frame_descr(const char *frame_descr) +{ + /* + * We need to parse the following string: + * "n alloc_1 alloc_2 ... alloc_n" + * where alloc_i looks like + * "offset size len name" + * or "offset size len name:line". + */ + + char token[64]; + unsigned long num_objects; + + if (!tokenize_frame_descr(&frame_descr, token, sizeof(token), + &num_objects)) + return; + + pr_err("\n"); + pr_err("this frame has %lu %s:\n", num_objects, + num_objects == 1 ? "object" : "objects"); + + while (num_objects--) { + unsigned long offset; + unsigned long size; + + /* access offset */ + if (!tokenize_frame_descr(&frame_descr, token, sizeof(token), + &offset)) + return; + /* access size */ + if (!tokenize_frame_descr(&frame_descr, token, sizeof(token), + &size)) + return; + /* name length (unused) */ + if (!tokenize_frame_descr(&frame_descr, NULL, 0, NULL)) + return; + /* object name */ + if (!tokenize_frame_descr(&frame_descr, token, sizeof(token), + NULL)) + return; + + /* Strip line number; without filename it's not very helpful. */ + strreplace(token, ':', '\0'); + + /* Finally, print object information. */ + pr_err(" [%lu, %lu) '%s'", offset, offset + size, token); + } +} + +static bool __must_check get_address_stack_frame_info(const void *addr, + unsigned long *offset, + const char **frame_descr, + const void **frame_pc) +{ + unsigned long aligned_addr; + unsigned long mem_ptr; + const u8 *shadow_bottom; + const u8 *shadow_ptr; + const unsigned long *frame; + + BUILD_BUG_ON(IS_ENABLED(CONFIG_STACK_GROWSUP)); + + /* + * NOTE: We currently only support printing frame information for + * accesses to the task's own stack. + */ + if (!object_is_on_stack(addr)) + return false; + + aligned_addr = round_down((unsigned long)addr, sizeof(long)); + mem_ptr = round_down(aligned_addr, KASAN_GRANULE_SIZE); + shadow_ptr = kasan_mem_to_shadow((void *)aligned_addr); + shadow_bottom = kasan_mem_to_shadow(end_of_stack(current)); + + while (shadow_ptr >= shadow_bottom && *shadow_ptr != KASAN_STACK_LEFT) { + shadow_ptr--; + mem_ptr -= KASAN_GRANULE_SIZE; + } + + while (shadow_ptr >= shadow_bottom && *shadow_ptr == KASAN_STACK_LEFT) { + shadow_ptr--; + mem_ptr -= KASAN_GRANULE_SIZE; + } + + if (shadow_ptr < shadow_bottom) + return false; + + frame = (const unsigned long *)(mem_ptr + KASAN_GRANULE_SIZE); + if (frame[0] != KASAN_CURRENT_STACK_FRAME_MAGIC) { + pr_err("KASAN internal error: frame info validation failed; invalid marker: %lu\n", + frame[0]); + return false; + } + + *offset = (unsigned long)addr - (unsigned long)frame; + *frame_descr = (const char *)frame[1]; + *frame_pc = (void *)frame[2]; + + return true; +} + +void print_address_stack_frame(const void *addr) +{ + unsigned long offset; + const char *frame_descr; + const void *frame_pc; + + if (!get_address_stack_frame_info(addr, &offset, &frame_descr, + &frame_pc)) + return; + + /* + * get_address_stack_frame_info only returns true if the given addr is + * on the current task's stack. + */ + pr_err("\n"); + pr_err("addr %px is located in stack of task %s/%d at offset %lu in frame:\n", + addr, current->comm, task_pid_nr(current), offset); + pr_err(" %pS\n", frame_pc); + + if (!frame_descr) + return; + + print_decoded_frame_descr(frame_descr); +} +#endif /* CONFIG_KASAN_STACK */ + #define DEFINE_ASAN_REPORT_LOAD(size) \ void __asan_report_load##size##_noabort(unsigned long addr) \ { \ _