From patchwork Mon Dec 13 21:54:22 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: 12674683 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 5985EC433EF for ; Mon, 13 Dec 2021 22:06:34 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E46336B009C; Mon, 13 Dec 2021 16:54:59 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id DF4AE6B009D; Mon, 13 Dec 2021 16:54:59 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id CBDB66B009E; Mon, 13 Dec 2021 16:54:59 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0184.hostedemail.com [216.40.44.184]) by kanga.kvack.org (Postfix) with ESMTP id BDFBA6B009C for ; Mon, 13 Dec 2021 16:54:59 -0500 (EST) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 8409982499B9 for ; Mon, 13 Dec 2021 21:54:49 +0000 (UTC) X-FDA: 78914126298.10.37EBEE2 Received: from out0.migadu.com (out0.migadu.com [94.23.1.103]) by imf15.hostedemail.com (Postfix) with ESMTP id 6BFB9A0006 for ; Mon, 13 Dec 2021 21:54:45 +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=1639432487; 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=6sq+eBKmPs7noJHajriN1+v4kOdtPX3nQQgZ/NueHSg=; b=xYHLkvnv9JFRRnzHB3lJddCqg4ES9wbd7eg73CVA4GkMBh0PeI5bfxhpubYdr8RoCOYQtp ZZecmK3Gsc0PD2vMEvUQFeEAm31A7Rg7jW8vgiFMEN1OKAzDmKkDYw/P61hXrzLmCE9XcX JbDPvvsg/65jGzb9/MP8N0dqoyMhusk= From: andrey.konovalov@linux.dev To: Marco Elver , Alexander Potapenko , Andrew Morton Cc: Andrey Konovalov , Dmitry Vyukov , Andrey Ryabinin , kasan-dev@googlegroups.com, linux-mm@kvack.org, Vincenzo Frascino , Catalin Marinas , Will Deacon , Mark Rutland , linux-arm-kernel@lists.infradead.org, Peter Collingbourne , Evgenii Stepanov , linux-kernel@vger.kernel.org, Andrey Konovalov Subject: [PATCH mm v3 26/38] kasan, vmalloc: don't unpoison VM_ALLOC pages before mapping Date: Mon, 13 Dec 2021 22:54:22 +0100 Message-Id: <1a2b5e3047faf05e5c11a9080c3f97a9b9b4c383.1639432170.git.andreyknvl@google.com> In-Reply-To: References: MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-Migadu-Auth-User: andrey.konovalov@linux.dev X-Stat-Signature: 3o9eiuchpispzf3sdc9w1b9k1ox68of4 Authentication-Results: imf15.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=xYHLkvnv; dmarc=pass (policy=none) header.from=linux.dev; spf=pass (imf15.hostedemail.com: domain of andrey.konovalov@linux.dev designates 94.23.1.103 as permitted sender) smtp.mailfrom=andrey.konovalov@linux.dev X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 6BFB9A0006 X-HE-Tag: 1639432485-983464 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 Make 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 --- Changes v2->v3: - Update patch description. --- mm/vmalloc.c | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 58bd2f7f86d7..9a6862e274df 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; } @@ -3104,6 +3112,12 @@ 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. @@ -3799,7 +3813,11 @@ 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);