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: 12694243 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id E4847C433F5 for ; Tue, 30 Nov 2021 22:22:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=/6v1WX73ZqPcywhE0+3fjIIJPZ/CyJE/ibcLmOLYEms=; b=ytDK7pvtd8ALfs h5OjI9kNaM5i0AvH3HUi3h40PI23pcaLeX8w2vRjpqfIQehvd7kq16oS/KcQap+TsLwiCZADW2MYY 3fCCqcQsDgJzbzv4fRIRjGnT/9CPeXfmuUGYURAFHOrxGwSlZ1S6EHCm3ZsdF5NogN7lYLtfu+Rag wLiXcJlSwI9iApnUqc7F2CvViWYWYqDjdGJcMWbWPl0eVWQCfiQ0GpK9ODqc0Xe+UymSUQHEoQ/oN fbGiLY8pVulpJ/9lT9jPW2e5i+TUiTEDW3XJtjY+t06UU9wjygi9Bcrnde/tqvQPgLH4yQ623wR94 xruedHaxHbi++Mx5f2aQ==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1msBU1-006zK0-U6; Tue, 30 Nov 2021 22:20:19 +0000 Received: from out2.migadu.com ([188.165.223.204]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1msBIC-006ujv-Tn for linux-arm-kernel@lists.infradead.org; Tue, 30 Nov 2021 22:08:06 +0000 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-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20211130_140805_166793_CBFCDF35 X-CRM114-Status: GOOD ( 14.42 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org 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);