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=-17.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_IN_DEF_DKIM_WL 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 BD9F4C388F9 for ; Wed, 11 Nov 2020 14:25:44 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id F1F2C20795 for ; Wed, 11 Nov 2020 14:25:43 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="MhI88VRy" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F1F2C20795 Authentication-Results: mail.kernel.org; dmarc=fail (p=reject dis=none) header.from=google.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 2F6D46B0070; Wed, 11 Nov 2020 09:25:43 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 281206B0074; Wed, 11 Nov 2020 09:25:43 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 0D2A06B0075; Wed, 11 Nov 2020 09:25:43 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0144.hostedemail.com [216.40.44.144]) by kanga.kvack.org (Postfix) with ESMTP id C04306B0070 for ; Wed, 11 Nov 2020 09:25:42 -0500 (EST) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 6484A180AD802 for ; Wed, 11 Nov 2020 14:25:42 +0000 (UTC) X-FDA: 77472360924.02.sand90_3a06c59272fe Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin02.hostedemail.com (Postfix) with ESMTP id 384C810097AA1 for ; Wed, 11 Nov 2020 14:25:42 +0000 (UTC) X-HE-Tag: sand90_3a06c59272fe X-Filterd-Recvd-Size: 18778 Received: from mail-qv1-f66.google.com (mail-qv1-f66.google.com [209.85.219.66]) by imf49.hostedemail.com (Postfix) with ESMTP for ; Wed, 11 Nov 2020 14:25:41 +0000 (UTC) Received: by mail-qv1-f66.google.com with SMTP id q7so927188qvt.12 for ; Wed, 11 Nov 2020 06:25:40 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc:content-transfer-encoding; bh=ivzJGCKhLp1x2v+oY17etQZN4NoUxQRVrZrrn1pxmzQ=; b=MhI88VRyKnCSohVt/b/8moDNfsbfFZlYNQiqzxMiCoC0YdUE3yesZOW9r3lkab0qdi nLTsNDYTtZW7/Tx7SbsMMFaYfEwfshUShKuAY87B4CS5Pv9u+9X/LS2GlP8KwZfgCD4G lYq0JxA7S0Jo9A4VX9wDC3zvrK8+nuwTGlMXYf2znZPt3+b2N8VcU+DkKtBOXETf6Gge qFuGoVHNqeKDPhK3zoi5jB8MprtBffAZxECn7RRrQxhmyjg0o4EwwYgfsBSeCq9MmzX2 Yt/EjBmaMtq9i8xzhStc5QGXB83wuDF64VU6zHPRoKyQNk0yYjg58xjXYkFaOIa5FJT1 HzvQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc:content-transfer-encoding; bh=ivzJGCKhLp1x2v+oY17etQZN4NoUxQRVrZrrn1pxmzQ=; b=OCWU4BhGMEoqEx0HfUmN8pRP71sbJw2bg3m2BHFQTTHYWxS7AWH0upwxbc/8WYiVVD oR88Ie4ot5MhfKLBoeDXpiT/AGs39+RavbUuVMaGb3YPVE74WvOtYEQ+q2YlieDq3UG1 vGfKnhlNXqugFRIfxt1teYTYWv92juJf7Tvm5YU7YsyCrEuEgZUxJHtbGTFr1qMioIiM pKaqAdUIboElvGw6znjlbXGm+UA6/X8z9wX+AdndtQw7/DI6AjJPBCpfT3tSIzy/QcAX WsmOomU4uR2RpeBj5lsOQmC0unF0DcEAJlOJ49mDgUFOa/WG3al/8evRtijPPpxagGUr mlVw== X-Gm-Message-State: AOAM532RW/R5SQmWgxGik5Zx1nU0vzUbBa7TLKPcLvbvjvxf++ahF/r8 0/45BNjBjuOCDcEPsjA9b9J9F6sOXNeWNYY7dbNPvg== X-Google-Smtp-Source: ABdhPJycer9vbmyDtpWZBUED3QtzZpM+KIzRxpVTeFzrW+cu9wtIRqmDDFvTkmO16e0dR39bfgELlSelu5U7Z3G6ggk= X-Received: by 2002:a0c:9e53:: with SMTP id z19mr24687355qve.23.1605104740021; Wed, 11 Nov 2020 06:25:40 -0800 (PST) MIME-Version: 1.0 References: In-Reply-To: From: Alexander Potapenko Date: Wed, 11 Nov 2020 15:25:28 +0100 Message-ID: Subject: Re: [PATCH v9 14/44] kasan: decode stack frame only with KASAN_STACK_ENABLE To: Andrey Konovalov Cc: Catalin Marinas , Will Deacon , Vincenzo Frascino , Dmitry Vyukov , Andrey Ryabinin , Marco Elver , Evgenii Stepanov , Branislav Rankov , Kevin Brodsky , Andrew Morton , kasan-dev , Linux ARM , Linux Memory Management List , LKML Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable 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: On Tue, Nov 10, 2020 at 11:11 PM Andrey Konovalov w= rote: > > 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. > > Signed-off-by: Andrey Konovalov > Signed-off-by: Vincenzo Frascino > Reviewed-by: Marco Elver Reviewed-by: Alexander Potapenko > --- > Change-Id: I084e3214f2b40dc0bef7c5a9fafdc6f5c42b06a2 > --- > mm/kasan/kasan.h | 6 ++ > mm/kasan/report.c | 162 -------------------------------------- > mm/kasan/report_generic.c | 162 ++++++++++++++++++++++++++++++++++++++ > 3 files changed, 168 insertions(+), 162 deletions(-) > > diff --git a/mm/kasan/kasan.h b/mm/kasan/kasan.h > index 3eff57e71ff5..d0cf61d4d70d 100644 > --- a/mm/kasan/kasan.h > +++ b/mm/kasan/kasan.h > @@ -169,6 +169,12 @@ 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); > diff --git a/mm/kasan/report.c b/mm/kasan/report.c > index fff0c7befbfe..b18d193f7f58 100644 > --- a/mm/kasan/report.c > +++ b/mm/kasan/report.c > @@ -211,168 +211,6 @@ static inline bool init_task_stack_addr(const void = *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 =3D strchr(*frame_descr, ' '); > - > - if (sep =3D=3D NULL) > - sep =3D *frame_descr + strlen(*frame_descr); > - > - if (token !=3D NULL) { > - const size_t tok_len =3D sep - *frame_descr; > - > - if (tok_len + 1 > max_tok_len) { > - pr_err("KASAN internal error: frame description t= oo 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 =3D sep + 1; > - > - if (value !=3D 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 =3D=3D 1 ? "object" : "objects"); > - > - while (num_objects--) { > - unsigned long offset; > - unsigned long size; > - > - /* access offset */ > - if (!tokenize_frame_descr(&frame_descr, token, sizeof(tok= en), > - &offset)) > - return; > - /* access size */ > - if (!tokenize_frame_descr(&frame_descr, token, sizeof(tok= en), > - &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(tok= en), > - NULL)) > - return; > - > - /* Strip line number; without filename it's not very help= ful. */ > - 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 *offs= et, > - 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 =3D round_down((unsigned long)addr, sizeof(long)); > - mem_ptr =3D round_down(aligned_addr, KASAN_GRANULE_SIZE); > - shadow_ptr =3D kasan_mem_to_shadow((void *)aligned_addr); > - shadow_bottom =3D kasan_mem_to_shadow(end_of_stack(current)); > - > - while (shadow_ptr >=3D shadow_bottom && *shadow_ptr !=3D KASAN_ST= ACK_LEFT) { > - shadow_ptr--; > - mem_ptr -=3D KASAN_GRANULE_SIZE; > - } > - > - while (shadow_ptr >=3D shadow_bottom && *shadow_ptr =3D=3D KASAN_= STACK_LEFT) { > - shadow_ptr--; > - mem_ptr -=3D KASAN_GRANULE_SIZE; > - } > - > - if (shadow_ptr < shadow_bottom) > - return false; > - > - frame =3D (const unsigned long *)(mem_ptr + KASAN_GRANULE_SIZE); > - if (frame[0] !=3D KASAN_CURRENT_STACK_FRAME_MAGIC) { > - pr_err("KASAN internal error: frame info validation faile= d; invalid marker: %lu\n", > - frame[0]); > - return false; > - } > - > - *offset =3D (unsigned long)addr - (unsigned long)frame; > - *frame_descr =3D (const char *)frame[1]; > - *frame_pc =3D (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 ad= dr 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 =3D kasan_addr_to_page(addr); > diff --git a/mm/kasan/report_generic.c b/mm/kasan/report_generic.c > index 7d5b9e5c7cfe..b543a1ed6078 100644 > --- a/mm/kasan/report_generic.c > +++ b/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_access_info *= info) > 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 =3D strchr(*frame_descr, ' '); > + > + if (sep =3D=3D NULL) > + sep =3D *frame_descr + strlen(*frame_descr); > + > + if (token !=3D NULL) { > + const size_t tok_len =3D sep - *frame_descr; > + > + if (tok_len + 1 > max_tok_len) { > + pr_err("KASAN internal error: frame description t= oo 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 =3D sep + 1; > + > + if (value !=3D 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 =3D=3D 1 ? "object" : "objects"); > + > + while (num_objects--) { > + unsigned long offset; > + unsigned long size; > + > + /* access offset */ > + if (!tokenize_frame_descr(&frame_descr, token, sizeof(tok= en), > + &offset)) > + return; > + /* access size */ > + if (!tokenize_frame_descr(&frame_descr, token, sizeof(tok= en), > + &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(tok= en), > + NULL)) > + return; > + > + /* Strip line number; without filename it's not very help= ful. */ > + 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 *offs= et, > + 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 =3D round_down((unsigned long)addr, sizeof(long)); > + mem_ptr =3D round_down(aligned_addr, KASAN_GRANULE_SIZE); > + shadow_ptr =3D kasan_mem_to_shadow((void *)aligned_addr); > + shadow_bottom =3D kasan_mem_to_shadow(end_of_stack(current)); > + > + while (shadow_ptr >=3D shadow_bottom && *shadow_ptr !=3D KASAN_ST= ACK_LEFT) { > + shadow_ptr--; > + mem_ptr -=3D KASAN_GRANULE_SIZE; > + } > + > + while (shadow_ptr >=3D shadow_bottom && *shadow_ptr =3D=3D KASAN_= STACK_LEFT) { > + shadow_ptr--; > + mem_ptr -=3D KASAN_GRANULE_SIZE; > + } > + > + if (shadow_ptr < shadow_bottom) > + return false; > + > + frame =3D (const unsigned long *)(mem_ptr + KASAN_GRANULE_SIZE); > + if (frame[0] !=3D KASAN_CURRENT_STACK_FRAME_MAGIC) { > + pr_err("KASAN internal error: frame info validation faile= d; invalid marker: %lu\n", > + frame[0]); > + return false; > + } > + > + *offset =3D (unsigned long)addr - (unsigned long)frame; > + *frame_descr =3D (const char *)frame[1]; > + *frame_pc =3D (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 ad= dr 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) \ > { \ > -- > 2.29.2.222.g5d2a92d10f8-goog > --=20 Alexander Potapenko Software Engineer Google Germany GmbH Erika-Mann-Stra=C3=9Fe, 33 80636 M=C3=BCnchen Gesch=C3=A4ftsf=C3=BChrer: Paul Manicle, Halimah DeLaine Prado Registergericht und -nummer: Hamburg, HRB 86891 Sitz der Gesellschaft: Hamburg