From patchwork Tue Nov 30 22:08:01 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: andrey.konovalov@linux.dev X-Patchwork-Id: 12648285 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0799CC433EF for ; Tue, 30 Nov 2021 22:13:10 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 6A06D6B0087; Tue, 30 Nov 2021 17:08:15 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 677F36B0088; Tue, 30 Nov 2021 17:08:15 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 566BF6B0089; Tue, 30 Nov 2021 17:08:15 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0194.hostedemail.com [216.40.44.194]) by kanga.kvack.org (Postfix) with ESMTP id 46A746B0087 for ; Tue, 30 Nov 2021 17:08:15 -0500 (EST) Received: from smtpin03.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 092DF180AA9AE for ; Tue, 30 Nov 2021 22:08:05 +0000 (UTC) X-FDA: 78866985330.03.419D269 Received: from out2.migadu.com (out2.migadu.com [188.165.223.204]) by imf24.hostedemail.com (Postfix) with ESMTP id 466DDB00009F for ; Tue, 30 Nov 2021 22:07:59 +0000 (UTC) X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1638310083; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=CceoAuXc8ztt6c/41GK5sR1YQRKzgrFVIEpBFl753js=; b=xp8MsUnB5BFCaXQy2k5xnv/wQY4pHXZcBNpppZ/1PrYh0SQUDDYlmoRG/NNRkZXmK0UAWE SvLikYAEayl69lqn5gywYTPR07bS5gG61K2RRPu5/WdY2Ce9Jp5cCo9TM8TEEHoFL9kdpf s5K1oextKKqxI6p/G02TWr5VgVOiiiw= From: andrey.konovalov@linux.dev To: Marco Elver , Alexander Potapenko , Vincenzo Frascino , Catalin Marinas , Peter Collingbourne Cc: Andrey Konovalov , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, Andrew Morton , linux-mm@kvack.org, Will Deacon , linux-arm-kernel@lists.infradead.org, Evgenii Stepanov , linux-kernel@vger.kernel.org, Andrey Konovalov Subject: [PATCH 25/31] kasan, vmalloc: don't unpoison VM_ALLOC pages before mapping Date: Tue, 30 Nov 2021 23:08:01 +0100 Message-Id: <0b79da9e534bfa35d11154b940095df23ee68a16.1638308023.git.andreyknvl@google.com> In-Reply-To: References: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: linux.dev X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 466DDB00009F Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=xp8MsUnB; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf24.hostedemail.com: domain of andrey.konovalov@linux.dev designates 188.165.223.204 as permitted sender) smtp.mailfrom=andrey.konovalov@linux.dev X-Stat-Signature: a34p8h7nqrtj5fir8in7q9s1xj65ecsq X-HE-Tag: 1638310079-181223 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 This patch makes KASAN unpoison vmalloc mappings after that have been mapped in when it's possible: for vmalloc() (indentified via VM_ALLOC) and vm_map_ram(). The reasons for this are: - For vmalloc() and vm_map_ram(): pages don't get unpoisoned in case mapping them fails. - For vmalloc(): HW_TAGS KASAN needs pages to be mapped to set tags via kasan_unpoison_vmalloc(). Signed-off-by: Andrey Konovalov --- mm/vmalloc.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index f37d0ed99bf9..82ef1e27e2e4 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -2208,14 +2208,15 @@ void *vm_map_ram(struct page **pages, unsigned int count, int node) mem = (void *)addr; } - mem = kasan_unpoison_vmalloc(mem, size); - if (vmap_pages_range(addr, addr + size, PAGE_KERNEL, pages, PAGE_SHIFT) < 0) { vm_unmap_ram(mem, count); return NULL; } + /* Mark the pages as accessible after they were mapped in. */ + mem = kasan_unpoison_vmalloc(mem, size); + return mem; } EXPORT_SYMBOL(vm_map_ram); @@ -2443,7 +2444,14 @@ static struct vm_struct *__get_vm_area_node(unsigned long size, setup_vmalloc_vm(area, va, flags, caller); - area->addr = kasan_unpoison_vmalloc(area->addr, requested_size); + /* + * For VM_ALLOC mappings, __vmalloc_node_range() mark the pages as + * accessible after they are mapped in. + * Otherwise, as the pages can be mapped outside of vmalloc code, + * mark them now as a best-effort approach. + */ + if (!(flags & VM_ALLOC)) + area->addr = kasan_unpoison_vmalloc(area->addr, requested_size); return area; } @@ -3072,6 +3080,12 @@ void *__vmalloc_node_range(unsigned long size, unsigned long align, if (!addr) goto fail; + /* + * Mark the pages for VM_ALLOC mappings as accessible after they were + * mapped in. + */ + addr = kasan_unpoison_vmalloc(addr, real_size); + /* * In this function, newly allocated vm_struct has VM_UNINITIALIZED * flag. It means that vm_struct is not fully initialized. @@ -3766,7 +3780,11 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, } spin_unlock(&vmap_area_lock); - /* mark allocated areas as accessible */ + /* + * Mark allocated areas as accessible. + * As the pages are mapped outside of vmalloc code, + * mark them now as a best-effort approach. + */ for (area = 0; area < nr_vms; area++) vms[area]->addr = kasan_unpoison_vmalloc(vms[area]->addr, vms[area]->size);