From patchwork Tue May 11 09:00:03 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zheyu Ma X-Patchwork-Id: 12250267 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=-15.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 47D14C433ED for ; Tue, 11 May 2021 09:00:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 10386613AF for ; Tue, 11 May 2021 09:00:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231251AbhEKJBh (ORCPT ); Tue, 11 May 2021 05:01:37 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:58860 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231223AbhEKJB2 (ORCPT ); Tue, 11 May 2021 05:01:28 -0400 Received: from mail-pl1-x62f.google.com (mail-pl1-x62f.google.com [IPv6:2607:f8b0:4864:20::62f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 09D31C061574; Tue, 11 May 2021 02:00:21 -0700 (PDT) Received: by mail-pl1-x62f.google.com with SMTP id h7so10522590plt.1; Tue, 11 May 2021 02:00:21 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id; bh=BYzneVRTchqVV1zpNyvC8n1HUVYTmsXKKmbtKhzdA60=; b=ZKcdUsvMYNfUEZfqAihci5VgiaIDTNNtyAiH3mj/BTtwa0uFi721uB4ttG5THTjDYM 4XkMPphSCqUicnU5bmWLL5oX3xxHhAPz+ruB1zo34xx9XM35rrdQdmfi//ToLXAVWnTi JujF5zpSGjjVvoSlVwW4wo/fY8SXk0rtwBuPoS807IliQrLNAEf0lUFZeFjI8lyug502 S0lhS28IbVeX/EWy0mAYgzBaI2d2BfaKkQ6T+GAAhApGSPNjcRdLA4v+G80L634b6wJL oL3uyMTJvhxeiJYmQtvtSFzmfgCf5S18Tw2gRpv7yBsy0Tp7E88D5PThe2gSiyUeSuec 1Zww== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=BYzneVRTchqVV1zpNyvC8n1HUVYTmsXKKmbtKhzdA60=; b=G2Ou2dFT/Faxep2fTV34uMKBpaAnKvooe1umTkVKqocBGOJMSSHT/aKRp1856LndPd cXgMfpDzE2oViMKrbcLmxFyRigvQbVbH3BXkHD0v1J8lbJN7gV+fPnkq7Zc/LUuBQvy9 f6gakD2PonD4l2ZfSMY2RVbtTalJKlLtCZzlwOaSJlZzb5d2+V6GQpho7o2QqT2yEUvO r0ErCXLJpRXrhcUznB+TMx+DpI9Wtoo75lrf7liQ674dZmLEldEm9lYoisrNhZt9oPD8 YuIjKBHnCv1r6zsZgFrXT7ckdzlck42dvI1t3jsNn4GlpkxQVEr7Uj2XS2lAihVqeDdj IMWg== X-Gm-Message-State: AOAM532sAHIKp27QCQ/aqTNjZdPvoNsc7NecbnXlIvKppYP22KMQdI/i go3dmyj3fT4ctcXaCLguzA== X-Google-Smtp-Source: ABdhPJwS6kmQCvxZrrVYV97R5SCvRCoEKR6yTQFMawz4zCxP75IhvVKILA2I4Vm4TttSJdWrqAbEnQ== X-Received: by 2002:a17:902:988d:b029:ef:68aa:d775 with SMTP id s13-20020a170902988db02900ef68aad775mr918914plp.57.1620723620444; Tue, 11 May 2021 02:00:20 -0700 (PDT) Received: from vultr.guest ([107.191.53.97]) by smtp.gmail.com with ESMTPSA id n18sm13225778pgj.71.2021.05.11.02.00.18 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Tue, 11 May 2021 02:00:19 -0700 (PDT) From: Zheyu Ma To: mchehab@kernel.org Cc: sean@mess.org, zheyuma97@gmail.com, arnd@arndb.de, linux-media@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH] media: b2c2: Add missing check in flexcop_pci_isr: Date: Tue, 11 May 2021 09:00:03 +0000 Message-Id: <1620723603-30912-1-git-send-email-zheyuma97@gmail.com> X-Mailer: git-send-email 2.7.4 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org A out-of-bounds bug can be triggered by an interrupt, the reason for this bug is the lack of checking of register values. In flexcop_pci_isr, the driver reads value from a register and uses it as a dma address. Finally, this address will be passed to the count parameter of find_next_packet. If this value is larger than the size of dma, the index of buffer will be out-of-bounds. Fix this by adding a check after reading the value of the register. The following KASAN report reveals it: BUG: KASAN: slab-out-of-bounds in find_next_packet drivers/media/dvb-core/dvb_demux.c:528 [inline] BUG: KASAN: slab-out-of-bounds in _dvb_dmx_swfilter drivers/media/dvb-core/dvb_demux.c:572 [inline] BUG: KASAN: slab-out-of-bounds in dvb_dmx_swfilter+0x3fa/0x420 drivers/media/dvb-core/dvb_demux.c:603 Read of size 1 at addr ffff8880608c00a0 by task swapper/2/0 CPU: 2 PID: 0 Comm: swapper/2 Not tainted 4.19.177-gdba4159c14ef #25 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0xec/0x156 lib/dump_stack.c:118 print_address_description+0x78/0x290 mm/kasan/report.c:256 kasan_report_error mm/kasan/report.c:354 [inline] kasan_report+0x25b/0x380 mm/kasan/report.c:412 __asan_report_load1_noabort+0x19/0x20 mm/kasan/report.c:430 find_next_packet drivers/media/dvb-core/dvb_demux.c:528 [inline] _dvb_dmx_swfilter drivers/media/dvb-core/dvb_demux.c:572 [inline] dvb_dmx_swfilter+0x3fa/0x420 drivers/media/dvb-core/dvb_demux.c:603 flexcop_pass_dmx_data+0x2e/0x40 drivers/media/common/b2c2/flexcop.c:167 flexcop_pci_isr+0x3d1/0x5d0 drivers/media/pci/b2c2/flexcop-pci.c:212 __handle_irq_event_percpu+0xfb/0x770 kernel/irq/handle.c:149 handle_irq_event_percpu+0x79/0x150 kernel/irq/handle.c:189 handle_irq_event+0xac/0x140 kernel/irq/handle.c:206 handle_fasteoi_irq+0x232/0x5c0 kernel/irq/chip.c:725 generic_handle_irq_desc include/linux/irqdesc.h:155 [inline] handle_irq+0x230/0x3a0 arch/x86/kernel/irq_64.c:87 do_IRQ+0xa7/0x1e0 arch/x86/kernel/irq.c:247 common_interrupt+0xf/0xf arch/x86/entry/entry_64.S:670 RIP: 0010:native_safe_halt+0x28/0x30 arch/x86/include/asm/irqflags.h:61 Code: 00 00 55 be 04 00 00 00 48 c7 c7 00 62 2f 8c 48 89 e5 e8 fb 31 e8 f8 8b 05 75 4f 8e 03 85 c0 7e 07 0f 00 2d 8a 61 66 00 fb f4 <5d> c3 90 90 90 90 90 90 0f 1f 44 00 00 55 48 89 e5 41 57 41 56 41 RSP: 0018:ffff88806b71fcc8 EFLAGS: 00000246 ORIG_RAX: ffffffffffffffde RAX: 0000000000000000 RBX: ffffffff8bde44c8 RCX: ffffffff88a11285 RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffffffff8c2f6200 RBP: ffff88806b71fcc8 R08: fffffbfff185ec40 R09: fffffbfff185ec40 R10: 0000000000000001 R11: fffffbfff185ec40 R12: 0000000000000002 R13: ffffffff8be9d6e0 R14: 0000000000000000 R15: 0000000000000000 arch_safe_halt arch/x86/include/asm/paravirt.h:94 [inline] default_idle+0x6f/0x360 arch/x86/kernel/process.c:557 arch_cpu_idle+0xf/0x20 arch/x86/kernel/process.c:548 default_idle_call+0x3b/0x60 kernel/sched/idle.c:93 cpuidle_idle_call kernel/sched/idle.c:153 [inline] do_idle+0x2ab/0x3c0 kernel/sched/idle.c:263 cpu_startup_entry+0xcb/0xe0 kernel/sched/idle.c:369 start_secondary+0x3b8/0x4e0 arch/x86/kernel/smpboot.c:271 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:243 Allocated by task 1: save_stack+0x43/0xd0 mm/kasan/kasan.c:448 set_track mm/kasan/kasan.c:460 [inline] kasan_kmalloc+0xad/0xe0 mm/kasan/kasan.c:553 kasan_slab_alloc+0x11/0x20 mm/kasan/kasan.c:490 slab_post_alloc_hook mm/slab.h:445 [inline] slab_alloc_node mm/slub.c:2741 [inline] slab_alloc mm/slub.c:2749 [inline] kmem_cache_alloc+0xeb/0x280 mm/slub.c:2754 kmem_cache_zalloc include/linux/slab.h:699 [inline] __kernfs_new_node+0xe2/0x6f0 fs/kernfs/dir.c:633 kernfs_new_node+0x9a/0x120 fs/kernfs/dir.c:693 __kernfs_create_file+0x5f/0x340 fs/kernfs/file.c:992 sysfs_add_file_mode_ns+0x22a/0x4e0 fs/sysfs/file.c:306 create_files fs/sysfs/group.c:63 [inline] internal_create_group+0x34e/0xc30 fs/sysfs/group.c:147 sysfs_create_group fs/sysfs/group.c:173 [inline] sysfs_create_groups+0x9c/0x140 fs/sysfs/group.c:200 driver_add_groups+0x3e/0x50 drivers/base/driver.c:129 bus_add_driver+0x3a5/0x790 drivers/base/bus.c:684 driver_register+0x1cd/0x410 drivers/base/driver.c:170 __pci_register_driver+0x197/0x200 drivers/pci/pci-driver.c:1411 cx88_audio_pci_driver_init+0x23/0x25 drivers/media/pci/cx88/cx88-alsa.c: 1017 do_one_initcall+0xe0/0x610 init/main.c:884 do_initcall_level init/main.c:952 [inline] do_initcalls init/main.c:960 [inline] do_basic_setup init/main.c:978 [inline] kernel_init_freeable+0x4d0/0x592 init/main.c:1145 kernel_init+0x18/0x190 init/main.c:1062 ret_from_fork+0x24/0x30 arch/x86/entry/entry_64.S:415 Freed by task 0: (stack is not available) The buggy address belongs to the object at ffff8880608c0000 which belongs to the cache kernfs_node_cache of size 160 The buggy address is located 0 bytes to the right of 160-byte region [ffff8880608c0000, ffff8880608c00a0) The buggy address belongs to the page: page:ffffea0001823000 count:1 mapcount:0 mapping:ffff88806bed1e00 index:0x0 compound_mapcount: 0 flags: 0x100000000008100(slab|head) raw: 0100000000008100 dead000000000100 dead000000000200 ffff88806bed1e00 raw: 0000000000000000 0000000000240024 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff8880608bff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880608c0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8880608c0080: 00 00 00 00 fc fc fc fc fc fc fc fc 00 00 00 00 ^ ffff8880608c0100: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8880608c0180: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ================================================================== Reported-by: Zheyu Ma Signed-off-by: Zheyu Ma --- drivers/media/pci/b2c2/flexcop-pci.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/media/pci/b2c2/flexcop-pci.c b/drivers/media/pci/b2c2/flexcop-pci.c index 6a4c7cb0ad0f..b03704c11a41 100644 --- a/drivers/media/pci/b2c2/flexcop-pci.c +++ b/drivers/media/pci/b2c2/flexcop-pci.c @@ -185,6 +185,8 @@ static irqreturn_t flexcop_pci_isr(int irq, void *dev_id) dma_addr_t cur_addr = fc->read_ibi_reg(fc,dma1_008).dma_0x8.dma_cur_addr << 2; u32 cur_pos = cur_addr - fc_pci->dma[0].dma_addr0; + if (cur_pos > fc_pci->dma[0].size*2) + goto error; deb_irq("%u irq: %08x cur_addr: %llx: cur_pos: %08x, last_cur_pos: %08x ", jiffies_to_usecs(jiffies - fc_pci->last_irq), @@ -225,6 +227,7 @@ static irqreturn_t flexcop_pci_isr(int irq, void *dev_id) ret = IRQ_NONE; } +error: spin_unlock_irqrestore(&fc_pci->irq_lock, flags); return ret; }