From patchwork Wed May 10 08:55:24 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Ruihan Li X-Patchwork-Id: 681145 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 136ECC77B7C for ; Wed, 10 May 2023 09:04:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S236975AbjEJJET (ORCPT ); Wed, 10 May 2023 05:04:19 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:55938 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236947AbjEJJEM (ORCPT ); Wed, 10 May 2023 05:04:12 -0400 Received: from pku.edu.cn (mx18.pku.edu.cn [162.105.129.181]) by lindbergh.monkeyblade.net (Postfix) with ESMTP id 7A6A230C7; Wed, 10 May 2023 02:03:53 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=pku.edu.cn; s=dkim; h=Received:From:To:Cc:Subject:Date: Message-Id:In-Reply-To:References:MIME-Version: Content-Transfer-Encoding; bh=FCdoZypKOCF7Yar38FzSX/85JDvNvpncqZ ++kam1a4o=; b=jvCCbw1WH+LNsraRFmaFWBu79Plkic4etlcBNT2Q9/Pu+Ozgbj 5yIQu+HzX+Df+l7RnwSSM/X2QK4J727QlDceCkFh0FJZTq57YTKR1/5mVne2XE0l REqck6axoRwbXR0l1nvzX5Hin4BdXaYw97JAI5ZYCwuvCumiC2g04qrys= Received: from localhost.localdomain (unknown [10.7.101.92]) by front01 (Coremail) with SMTP id 5oFpogBnb2cIXFtkW9d5Ag--.63159S3; Wed, 10 May 2023 16:55:42 +0800 (CST) From: Ruihan Li To: linux-mm@kvack.org Cc: linux-usb@vger.kernel.org, linux-kernel@vger.kernel.org, Pasha Tatashin , David Hildenbrand , Matthew Wilcox , Andrew Morton , Christoph Hellwig , Greg Kroah-Hartman , Ruihan Li , syzbot+fcf1a817ceb50935ce99@syzkaller.appspotmail.comm, stable@vger.kernel.org Subject: [PATCH 1/4] usb: usbfs: Enforce page requirements for mmap Date: Wed, 10 May 2023 16:55:24 +0800 Message-Id: <20230510085527.57953-2-lrh2000@pku.edu.cn> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20230510085527.57953-1-lrh2000@pku.edu.cn> References: <20230510085527.57953-1-lrh2000@pku.edu.cn> MIME-Version: 1.0 X-CM-TRANSID: 5oFpogBnb2cIXFtkW9d5Ag--.63159S3 X-Coremail-Antispam: 1UD129KBjvJXoWxXry7Gr1fXw4xWw13tF13urg_yoWrKF4kpF sxWr15CrW5tryxXrnxKFs8Za4Yvws5uFyUKrWxu3s3uF13J3sI9Fn5AFy5ZF1rJr4vgr1f tFn0krWYk3WUG37anT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBF1xkIjI8I6I8E6xAIw20EY4v20xvaj40_Wr0E3s1l1IIY67AE w4v_Jr0_Jr4l8cAvFVAK0II2c7xJM28CjxkF64kEwVA0rcxSw2x7M28EF7xvwVC0I7IYx2 IY67AKxVWDJVCq3wA2z4x0Y4vE2Ix0cI8IcVCY1x0267AKxVW0oVCq3wA2z4x0Y4vEx4A2 jsIE14v26rxl6s0DM28EF7xvwVC2z280aVCY1x0267AKxVW0oVCq3wAac4AC62xK8xCEY4 vEwIxC4wAS0I0E0xvYzxvE52x082IY62kv0487Mc02F40EFcxC0VAKzVAqx4xG6I80ewAv 7VC0I7IYx2IY67AKxVWUJVWUGwAv7VC2z280aVAFwI0_Jr0_Gr1lOx8S6xCaFVCjc4AY6r 1j6r4UM4x0Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwACI402YVCY1x02 628vn2kIc2xKxwCY02Avz4vE-syl42xK82IYc2Ij64vIr41l42xK82IY6x8ErcxFaVAv8V WkJr1UJwCFx2IqxVCFs4IE7xkEbVWUJVW8JwC20s026c02F40E14v26r1j6r18MI8I3I0E 7480Y4vE14v26r106r1rMI8E67AF67kF1VAFwI0_Jw0_GFylIxkGc2Ij64vIr41lIxAIcV C0I7IYx2IY67AKxVWUJVWUCwCI42IY6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1lIxAIcVCF 04k26cxKx2IYs7xG6r1j6r1xMIIF0xvEx4A2jsIE14v26r1j6r4UMIIF0xvEx4A2jsIEc7 CjxVAFwI0_Gr0_Gr1UYxBIdaVFxhVjvjDU0xZFpf9x0JUQZ23UUUUU= X-CM-SenderInfo: yssqiiarrvmko6sn3hxhgxhubq/1tbiAgEEBVPy770DbwAWsL Precedence: bulk List-ID: X-Mailing-List: linux-usb@vger.kernel.org The current implementation of usbdev_mmap uses usb_alloc_coherent to allocate memory pages that will later be mapped into the user space. Meanwhile, usb_alloc_coherent employs three different methods to allocate memory, as outlined below: * If hcd->localmem_pool is non-null, it uses gen_pool_dma_alloc to allocate memory. * If DMA is not available, it uses kmalloc to allocate memory. * Otherwise, it uses dma_alloc_coherent. However, it should be noted that gen_pool_dma_alloc does not guarantee that the resulting memory will be page-aligned. Furthermore, trying to map slab pages (i.e., memory allocated by kmalloc) into the user space is not resonable and can lead to problems, such as a type confusion bug when PAGE_TABLE_CHECK=y [1]. To address these issues, this patch introduces hcd_alloc_coherent_pages, which addresses the above two problems. Specifically, hcd_alloc_coherent_pages uses gen_pool_dma_alloc_align instead of gen_pool_dma_alloc to ensure that the memory is page-aligned. To replace kmalloc, hcd_alloc_coherent_pages directly allocates pages by calling __get_free_pages. Reported-by: syzbot+fcf1a817ceb50935ce99@syzkaller.appspotmail.comm Closes: https://lore.kernel.org/lkml/000000000000258e5e05fae79fc1@google.com/ [1] Cc: stable@vger.kernel.org Signed-off-by: Ruihan Li --- drivers/usb/core/buffer.c | 41 +++++++++++++++++++++++++++++++++++++++ drivers/usb/core/devio.c | 9 +++++---- include/linux/usb/hcd.h | 5 +++++ 3 files changed, 51 insertions(+), 4 deletions(-) diff --git a/drivers/usb/core/buffer.c b/drivers/usb/core/buffer.c index fbb087b72..6010ef9f5 100644 --- a/drivers/usb/core/buffer.c +++ b/drivers/usb/core/buffer.c @@ -172,3 +172,44 @@ void hcd_buffer_free( } dma_free_coherent(hcd->self.sysdev, size, addr, dma); } + +void *hcd_buffer_alloc_pages(struct usb_hcd *hcd, size_t size, + gfp_t mem_flags, dma_addr_t *dma) +{ + if (size == 0) + return NULL; + + if (hcd->localmem_pool) + return gen_pool_dma_alloc_align(hcd->localmem_pool, + size, dma, PAGE_SIZE); + + /* some USB hosts just use PIO */ + if (!hcd_uses_dma(hcd)) { + *dma = DMA_MAPPING_ERROR; + return (void *)__get_free_pages(mem_flags, + get_order(size)); + } + + return dma_alloc_coherent(hcd->self.sysdev, + size, dma, mem_flags); +} + +void hcd_buffer_free_pages(struct usb_hcd *hcd, size_t size, + void *addr, dma_addr_t dma) +{ + if (!addr) + return; + + if (hcd->localmem_pool) { + gen_pool_free(hcd->localmem_pool, + (unsigned long)addr, size); + return; + } + + if (!hcd_uses_dma(hcd)) { + free_pages((unsigned long)addr, get_order(size)); + return; + } + + dma_free_coherent(hcd->self.sysdev, size, addr, dma); +} diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c index e501a03d6..b4cf9e860 100644 --- a/drivers/usb/core/devio.c +++ b/drivers/usb/core/devio.c @@ -186,6 +186,7 @@ static int connected(struct usb_dev_state *ps) static void dec_usb_memory_use_count(struct usb_memory *usbm, int *count) { struct usb_dev_state *ps = usbm->ps; + struct usb_hcd *hcd = bus_to_hcd(ps->dev->bus); unsigned long flags; spin_lock_irqsave(&ps->lock, flags); @@ -194,8 +195,8 @@ static void dec_usb_memory_use_count(struct usb_memory *usbm, int *count) list_del(&usbm->memlist); spin_unlock_irqrestore(&ps->lock, flags); - usb_free_coherent(ps->dev, usbm->size, usbm->mem, - usbm->dma_handle); + hcd_buffer_free_pages(hcd, usbm->size, usbm->mem, + usbm->dma_handle); usbfs_decrease_memory_usage( usbm->size + sizeof(struct usb_memory)); kfree(usbm); @@ -247,8 +248,8 @@ static int usbdev_mmap(struct file *file, struct vm_area_struct *vma) goto error_decrease_mem; } - mem = usb_alloc_coherent(ps->dev, size, GFP_USER | __GFP_NOWARN, - &dma_handle); + mem = hcd_buffer_alloc_pages(hcd, size, GFP_USER | __GFP_NOWARN, + &dma_handle); if (!mem) { ret = -ENOMEM; goto error_free_usbm; diff --git a/include/linux/usb/hcd.h b/include/linux/usb/hcd.h index 094c77eaf..79f89109e 100644 --- a/include/linux/usb/hcd.h +++ b/include/linux/usb/hcd.h @@ -501,6 +501,11 @@ void *hcd_buffer_alloc(struct usb_bus *bus, size_t size, void hcd_buffer_free(struct usb_bus *bus, size_t size, void *addr, dma_addr_t dma); +void *hcd_buffer_alloc_pages(struct usb_hcd *hcd, size_t size, + gfp_t mem_flags, dma_addr_t *dma); +void hcd_buffer_free_pages(struct usb_hcd *hcd, size_t size, + void *addr, dma_addr_t dma); + /* generic bus glue, needed for host controllers that don't use PCI */ extern irqreturn_t usb_hcd_irq(int irq, void *__hcd);