From patchwork Wed Jun 30 13:53:12 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Potapenko X-Patchwork-Id: 469491 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=-26.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, 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,USER_AGENT_GIT,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 C36B6C11F65 for ; Wed, 30 Jun 2021 14:02:11 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AA04D61437 for ; Wed, 30 Jun 2021 14:02:11 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235978AbhF3OEi (ORCPT ); Wed, 30 Jun 2021 10:04:38 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48116 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236441AbhF3OEc (ORCPT ); Wed, 30 Jun 2021 10:04:32 -0400 Received: from mail-wr1-x449.google.com (mail-wr1-x449.google.com [IPv6:2a00:1450:4864:20::449]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A7338C09B095 for ; Wed, 30 Jun 2021 06:53:22 -0700 (PDT) Received: by mail-wr1-x449.google.com with SMTP id u16-20020a5d51500000b029011a6a17cf62so982751wrt.13 for ; Wed, 30 Jun 2021 06:53:22 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:message-id:mime-version:subject:from:to:cc; bh=dtH0IQ32mjHBoYzYQxUVAIZ8CYFo4XITSUGYSoSmvuA=; b=n8OrDYvB4lu0VQjvPLvwRPRKVdXxpGavb6OmQT8FlcNgMfasGdem5Xe1GYKcQwQLjF eqsZ/j6Bbhjo4RwvKBjlIA3938u9XJL5kaLuPE+AemK9oldlEH9n/O7jYcK/nQm3nGC/ Nodeu3rbuP4Y585s02N0WHsbJ2x4Ya5xzJ+LCr23nVTYRDU3lUUHASCch1pHLLVWRqzx qK2MpDY+sFqPLYhBmtHXEGpiDV69xYuYF+iyRSt6NjSv0Iz7u/pnaDM80+VLCjkUWrmC MpK9GM8HVUwec7+08q8yLbjtgq8yh5ljCYRIegMIXTR9+YZw73NAB/ZVV8kyVtmNYwC6 MRIQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:message-id:mime-version:subject:from:to:cc; bh=dtH0IQ32mjHBoYzYQxUVAIZ8CYFo4XITSUGYSoSmvuA=; b=A35VcCIc+AfCL4b+0JrPKqEKgT3vTyKRgwCJVn+u0Sd/p67i93Ei/2DpMyb62saMeg CPbJe7ubCFr9A5TcsOm4mJtBj58cSi+qf++TsxRm5wqpg+iZoyFIp+ATMBov2uL/GmpP mzcXDZ8iJqffXIjL4XddieW4qBpQIRb9vxuXBtoU4kkFIPjXtKZEFndaWnBts3Nc4aXX G1wpdWCezE/OgaDdVu7p0/Sd24F3z9+GS5WTj+9/7p578gRarpHmWAPKqZSPz8w5SibN QUrSPWiH54SvV1H42tQN1Lb+F3xO3AI9Cf9RKhYJh3ulQvxiDvhp7gf/w6siLFNdD05C Wyyg== X-Gm-Message-State: AOAM530wuwKKzvNXYdcEkwZMai41BGYMb39kLWHC/FIVk0fNZ6sgVuOR O+3DTypEBNWzWV/58gJs7eV7w18W92o= X-Google-Smtp-Source: ABdhPJxEOOWrV1qY5ZQLKAMR0q+wxV55Lm0/JLt5nQqznaRHf1ul1AN8gIWXEvsyC132NIT7onyLV9XuHP4= X-Received: from glider.muc.corp.google.com ([2a00:79e0:15:13:a3fc:e8:8089:1013]) (user=glider job=sendgmr) by 2002:a1c:638a:: with SMTP id x132mr4681717wmb.90.1625061200569; Wed, 30 Jun 2021 06:53:20 -0700 (PDT) Date: Wed, 30 Jun 2021 15:53:12 +0200 Message-Id: <20210630135313.1072577-1-glider@google.com> Mime-Version: 1.0 X-Mailer: git-send-email 2.32.0.93.g670b81a890-goog Subject: [PATCH v3 1/2] kfence: move the size check to the beginning of __kfence_alloc() From: Alexander Potapenko To: akpm@linux-foundation.org Cc: dvyukov@google.com, elver@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, stable@vger.kernel.org, gregkh@linuxfoundation.org, jrdr.linux@gmail.com, Alexander Potapenko Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Check the allocation size before toggling kfence_allocation_gate. This way allocations that can't be served by KFENCE will not result in waiting for another CONFIG_KFENCE_SAMPLE_INTERVAL without allocating anything. Suggested-by: Marco Elver Cc: Andrew Morton Cc: Dmitry Vyukov Cc: Marco Elver Cc: Greg Kroah-Hartman Cc: stable@vger.kernel.org # 5.12+ Signed-off-by: Alexander Potapenko --- mm/kfence/core.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/mm/kfence/core.c b/mm/kfence/core.c index 4d21ac44d5d35..33bb20d91bf6a 100644 --- a/mm/kfence/core.c +++ b/mm/kfence/core.c @@ -733,6 +733,13 @@ void kfence_shutdown_cache(struct kmem_cache *s) void *__kfence_alloc(struct kmem_cache *s, size_t size, gfp_t flags) { + /* + * Perform size check before switching kfence_allocation_gate, so that + * we don't disable KFENCE without making an allocation. + */ + if (size > PAGE_SIZE) + return NULL; + /* * allocation_gate only needs to become non-zero, so it doesn't make * sense to continue writing to it and pay the associated contention @@ -757,9 +764,6 @@ void *__kfence_alloc(struct kmem_cache *s, size_t size, gfp_t flags) if (!READ_ONCE(kfence_enabled)) return NULL; - if (size > PAGE_SIZE) - return NULL; - return kfence_guarded_alloc(s, size, flags); } From patchwork Wed Jun 30 13:53:13 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Alexander Potapenko X-Patchwork-Id: 469077 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=-26.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, 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, USER_AGENT_GIT, USER_IN_DEF_DKIM_WL autolearn=unavailable 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 F0C5FC11F68 for ; Wed, 30 Jun 2021 14:02:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CBB9161433 for ; Wed, 30 Jun 2021 14:02:10 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235594AbhF3OEh (ORCPT ); Wed, 30 Jun 2021 10:04:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48172 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236419AbhF3OEb (ORCPT ); Wed, 30 Jun 2021 10:04:31 -0400 Received: from mail-wm1-x349.google.com (mail-wm1-x349.google.com [IPv6:2a00:1450:4864:20::349]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 719C2C09B098 for ; Wed, 30 Jun 2021 06:53:24 -0700 (PDT) Received: by mail-wm1-x349.google.com with SMTP id z4-20020a1ce2040000b02901ee8d8e151eso2887180wmg.1 for ; Wed, 30 Jun 2021 06:53:24 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=date:in-reply-to:message-id:mime-version:references:subject:from:to :cc; bh=+15b98OXWiOrEiKCGfnfeWun+23tJxDlHH/wqzYj+20=; b=WXi9U1Vip4zaz3uBNoqN8a2omyzEGIgwOHLP1ooDckRXK/3CMYy03EQAgTTOXhOVsW jmdHZZ/yF5Ox7Fm9TusoCFGZ0KQvVrQD8c0rnGTiyFQ5kYC/sOYOD8RhHBbipYvQbkua hbATd9xyZ/oofzWhQ8fJ7n2GYJpKXKgTNuIMJvXeJKLcEiWZqt4oH73eDwErt19gObFj ePK7x/B/Ih4lHpv4jC71OibbjGzGJnOtWFBhjgCiOsYOdkloQyCxlTiyVmI87HqAC84k 5hnGD95dAdkRHC2aMiJXl0S33hgVvZJ0D7hXugZAczLXqj4T1Pd3i6XgmT6Mspy8gKv5 hxBg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=+15b98OXWiOrEiKCGfnfeWun+23tJxDlHH/wqzYj+20=; b=O7hQJR1qs2a6yHiCiOh4/uy5uqfk6USy1DZpDCvlDWZAwBHO8ChUIAywi8bH8wCTol r48G3B5O49/KDMrHiL2NdADpxOlbYUAAgroMt/XyDFEAHpR4p0wzY+440LxsvMDoTCZ5 KinR+4djv1PF7XrJsLZO93Ep3h+GooVX1f7YvRyXWSDRcRaGGuYj3FEmTTqrlsD5dhDa 9Wv0FZGn/UQ38iFO0WeAx+YnXxxpVfeJJDCOsdHYS7sC4AZEAckNrYNukNzdUZckc+kZ Ak9HNLoiiSpcR0PkUDDTqtv/Vfev5AB/32X4uuJnSwtPzDV7URxTHLzsVo6wWg9kYtkg iPjg== X-Gm-Message-State: AOAM530e7Py9kuxCyohQI0U6FUaw/FI0cpwMHAJrzHFvCe/nSInoDtKw HxZLYh6NrizmQgtIcM91ArvAa6CtqiY= X-Google-Smtp-Source: ABdhPJwZS4PQ4Qo0dgN0XnUOHZBFG5LDZXGSPSb4r9wuy4xppmcnGhAYbCV0/Tahu7HBzZ78p13B8Ltwwjo= X-Received: from glider.muc.corp.google.com ([2a00:79e0:15:13:a3fc:e8:8089:1013]) (user=glider job=sendgmr) by 2002:a05:600c:3504:: with SMTP id h4mr4860507wmq.118.1625061203035; Wed, 30 Jun 2021 06:53:23 -0700 (PDT) Date: Wed, 30 Jun 2021 15:53:13 +0200 In-Reply-To: <20210630135313.1072577-1-glider@google.com> Message-Id: <20210630135313.1072577-2-glider@google.com> Mime-Version: 1.0 References: <20210630135313.1072577-1-glider@google.com> X-Mailer: git-send-email 2.32.0.93.g670b81a890-goog Subject: [PATCH v3 2/2] kfence: skip all GFP_ZONEMASK allocations From: Alexander Potapenko To: akpm@linux-foundation.org Cc: dvyukov@google.com, elver@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org, stable@vger.kernel.org, gregkh@linuxfoundation.org, jrdr.linux@gmail.com, Alexander Potapenko Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org Allocation requests outside ZONE_NORMAL (MOVABLE, HIGHMEM or DNA) cannot be fulfilled by KFENCE, because KFENCE memory pool is located in a zone different from the requested one. Because callers of kmem_cache_alloc() may actually rely on the allocation to reside in the requested zone (e.g. memory allocations done with __GFP_DMA must be DMAable), skip all allocations done with GFP_ZONEMASK and/or respective SLAB flags (SLAB_CACHE_DMA and SLAB_CACHE_DMA32). Fixes: 0ce20dd84089 ("mm: add Kernel Electric-Fence infrastructure") Cc: Andrew Morton Cc: Dmitry Vyukov Cc: Marco Elver Cc: Greg Kroah-Hartman Cc: Souptick Joarder Cc: stable@vger.kernel.org # 5.12+ Signed-off-by: Alexander Potapenko --- v2: - added parentheses around the GFP clause, as requested by Marco v3: - ignore GFP_ZONEMASK, which also covers __GFP_HIGHMEM and __GFP_MOVABLE - move the flag check at the beginning of the function, as requested by Souptick Joarder --- mm/kfence/core.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/mm/kfence/core.c b/mm/kfence/core.c index 33bb20d91bf6a..d51f77329fd3c 100644 --- a/mm/kfence/core.c +++ b/mm/kfence/core.c @@ -740,6 +740,14 @@ void *__kfence_alloc(struct kmem_cache *s, size_t size, gfp_t flags) if (size > PAGE_SIZE) return NULL; + /* + * Skip allocations from non-default zones, including DMA. We cannot guarantee that pages + * in the KFENCE pool will have the requested properties (e.g. reside in DMAable memory). + */ + if ((flags & GFP_ZONEMASK) || + (s->flags & (SLAB_CACHE_DMA | SLAB_CACHE_DMA32))) + return NULL; + /* * allocation_gate only needs to become non-zero, so it doesn't make * sense to continue writing to it and pay the associated contention