From mboxrd@z Thu Jan 1 00:00:00 1970 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=-9.0 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 F3D77C433DF for ; Tue, 21 Jul 2020 13:52:54 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id C7CEB206E9 for ; Tue, 21 Jul 2020 13:52:54 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C7CEB206E9 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=bugs.launchpad.net Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:59778 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jxshS-0004A6-4B for qemu-devel@archiver.kernel.org; Tue, 21 Jul 2020 09:52:54 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:56206) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1jxsgE-0003Ed-Sp for qemu-devel@nongnu.org; Tue, 21 Jul 2020 09:51:38 -0400 Received: from indium.canonical.com ([91.189.90.7]:60904) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_128_GCM_SHA256:128) (Exim 4.90_1) (envelope-from ) id 1jxsgC-0007Hu-Cm for qemu-devel@nongnu.org; Tue, 21 Jul 2020 09:51:38 -0400 Received: from loganberry.canonical.com ([91.189.90.37]) by indium.canonical.com with esmtp (Exim 4.86_2 #2 (Debian)) id 1jxsg7-0008QD-FQ for ; Tue, 21 Jul 2020 13:51:31 +0000 Received: from loganberry.canonical.com (localhost [127.0.0.1]) by loganberry.canonical.com (Postfix) with ESMTP id 8E2792E8087 for ; Tue, 21 Jul 2020 13:51:30 +0000 (UTC) MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Date: Tue, 21 Jul 2020 13:44:37 -0000 From: Peter Maydell <1886362@bugs.launchpad.net> To: qemu-devel@nongnu.org X-Launchpad-Notification-Type: bug X-Launchpad-Bug: product=qemu; status=New; importance=Undecided; assignee=None; X-Launchpad-Bug-Information-Type: Public X-Launchpad-Bug-Private: no X-Launchpad-Bug-Security-Vulnerability: no X-Launchpad-Bug-Commenters: a1xndr jasowang philmd pjps pmaydell X-Launchpad-Bug-Reporter: Alexander Bulekov (a1xndr) X-Launchpad-Bug-Modifier: Peter Maydell (pmaydell) References: <159400349818.1851.7243060688419202620.malonedeb@wampee.canonical.com> <28d42c0f-99eb-a9c1-e3fc-98f11ee686ab@redhat.com> Message-ID: Subject: Re: [Bug 1886362] [NEW] Heap use-after-free in lduw_he_p through e1000e_write_to_rx_buffers X-Launchpad-Message-Rationale: Subscriber (QEMU) @qemu-devel-ml X-Launchpad-Message-For: qemu-devel-ml Precedence: bulk X-Generated-By: Launchpad (canonical.com); Revision="4809fcb62f445aaa3ae919f7f6c3cc7d156ea57a"; Instance="production-secrets-lazr.conf" X-Launchpad-Hash: 00a7fe2997473822b13188b7445623746b18c18d Received-SPF: none client-ip=91.189.90.7; envelope-from=bounces@canonical.com; helo=indium.canonical.com X-detected-operating-system: by eggs.gnu.org: First seen = 2020/07/21 08:20:43 X-ACL-Warn: Detected OS = Linux 3.11 and newer [fuzzy] X-Spam_score_int: -58 X-Spam_score: -5.9 X-Spam_bar: ----- X-Spam_report: (-5.9 / 5.0 requ) BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=1, RCVD_IN_DNSWL_HI=-5, RCVD_IN_MSPIKE_H3=-0.01, RCVD_IN_MSPIKE_WL=-0.01, SPF_HELO_NONE=0.001, SPF_NONE=0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Bug 1886362 <1886362@bugs.launchpad.net> Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Message-ID: <20200721134437.7rdxC0-WAR8Ap2c2g7ZdzmwpQV2CgTw8zwTc4hQjzwY@z> On Tue, 21 Jul 2020 at 14:21, Jason Wang wrote: > On 2020/7/21 =E4=B8=8B=E5=8D=888:31, Peter Maydell wrote: > > On Wed, 15 Jul 2020 at 09:36, Jason Wang wrote: > >> I think the point is to make DMA to MMIO work as real hardware. > > I wouldn't care to give a 100% guarantee that asking a real > > h/w device to DMA to itself didn't cause it to misbehave :-) > > It's more likely to happen-to-work because the DMA engine bit > > of a real h/w device is going to be decoupled somewhat from > > the respond-to-memory-transactions-for-registers logic, but > > it probably wasn't something the designers were actively > > thinking about either... > I think some device want such peer to peer transactions: > > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/D= ocumentation/driver-api/pci/p2pdma.rst That's a device DMAing to another device, not DMAing to *itself* (device-to-another-device DMA should work fine in QEMU). And only a very few devices will ever be sensible targets of the DMA -- basically things like nvme that have a looks-like-memory area, or special cases like doorbell registers. > > Yeah, this is the interesting part for QEMU. How should we > > structure devices that do DMA so that we can be sure that > > the device emulation at least doesn't crash? We could have > > a rule that all devices that do DMA must always postpone > > all of that DMA to a bottom-half, but that's a lot of > > refactoring of a lot of device code... > > > It looks to me the issue happens only for device with loopback I think in principle we have a problem for any device that (a) has memory mapped registers and (b) does DMA reads whose address is guest-controlled. Loopback isn't a requirement -- if the guest programs, say, an RX descriptor base address to point at the device's own registers, you get exactly the same kind of unexpected-reentrancy. thanks -- PMM -- = You received this bug notification because you are a member of qemu- devel-ml, which is subscribed to QEMU. https://bugs.launchpad.net/bugs/1886362 Title: Heap use-after-free in lduw_he_p through e1000e_write_to_rx_buffers Status in QEMU: New Bug description: Hello, This reproducer causes a heap-use-after free. QEMU Built with --enable-sa= nitizers: cat << EOF | ./i386-softmmu/qemu-system-i386 -M q35,accel=3Dqtest \ -qtest stdio -nographic -monitor none -serial none outl 0xcf8 0x80001010 outl 0xcfc 0xe1020000 outl 0xcf8 0x80001014 outl 0xcf8 0x80001004 outw 0xcfc 0x7 outl 0xcf8 0x800010a2 write 0xe102003b 0x1 0xff write 0xe1020103 0x1e 0xffffff055c5e5c30be4511d084fffffffffffffffffffffff= fffffffffff write 0xe1020420 0x4 0xffffffff write 0xe1020424 0x4 0xffffffff write 0xe102042b 0x1 0xff write 0xe1020430 0x4 0x055c5e5c write 0x5c041 0x1 0x04 write 0x5c042 0x1 0x02 write 0x5c043 0x1 0xe1 write 0x5c048 0x1 0x8a write 0x5c04a 0x1 0x31 write 0x5c04b 0x1 0xff write 0xe1020403 0x1 0xff EOF The Output: =3D=3D22689=3D=3DERROR: AddressSanitizer: heap-use-after-free on address = 0x62500026800e at pc 0x55b93bb18bfa bp 0x7fffdbe844f0 sp 0x7fffdbe83cb8 READ of size 2 at 0x62500026800e thread T0 #0 in __asan_memcpy (/build/i386-softmmu/qemu-system-i386+) #1 in lduw_he_p /include/qemu/bswap.h:332:5 #2 in ldn_he_p /include/qemu/bswap.h:550:1 #3 in flatview_write_continue /exec.c:3145:19 #4 in flatview_write /exec.c:3186:14 #5 in address_space_write /exec.c:3280:18 #6 in address_space_rw /exec.c:3290:16 #7 in dma_memory_rw_relaxed /include/sysemu/dma.h:87:18 #8 in dma_memory_rw /include/sysemu/dma.h:113:12 #9 in pci_dma_rw /include/hw/pci/pci.h:789:5 #10 in pci_dma_write /include/hw/pci/pci.h:802:12 #11 in e1000e_write_to_rx_buffers /hw/net/e1000e_core.c:1412:9 #12 in e1000e_write_packet_to_guest /hw/net/e1000e_core.c:1582:21 #13 in e1000e_receive_iov /hw/net/e1000e_core.c:1709:9 #14 in e1000e_nc_receive_iov /hw/net/e1000e.c:213:12 #15 in net_tx_pkt_sendv /hw/net/net_tx_pkt.c:544:9 #16 in net_tx_pkt_send /hw/net/net_tx_pkt.c:620:9 #17 in net_tx_pkt_send_loopback /hw/net/net_tx_pkt.c:633:11 #18 in e1000e_tx_pkt_send /hw/net/e1000e_core.c:664:16 #19 in e1000e_process_tx_desc /hw/net/e1000e_core.c:743:17 #20 in e1000e_start_xmit /hw/net/e1000e_core.c:934:9 #21 in e1000e_set_tctl /hw/net/e1000e_core.c:2431:9 #22 in e1000e_core_write /hw/net/e1000e_core.c:3265:9 #23 in e1000e_mmio_write /hw/net/e1000e.c:109:5 #24 in memory_region_write_accessor /memory.c:483:5 #25 in access_with_adjusted_size /memory.c:544:18 #26 in memory_region_dispatch_write /memory.c:1476:16 #27 in flatview_write_continue /exec.c:3146:23 #28 in flatview_write /exec.c:3186:14 #29 in address_space_write /exec.c:3280:18 #30 in qtest_process_command /qtest.c:567:9 #31 in qtest_process_inbuf /qtest.c:710:9 #32 in qtest_read /qtest.c:722:5 #33 in qemu_chr_be_write_impl /chardev/char.c:188:9 #34 in qemu_chr_be_write /chardev/char.c:200:9 #35 in fd_chr_read /chardev/char-fd.c:68:9 #36 in qio_channel_fd_source_dispatch /io/channel-watch.c:84:12 #37 in g_main_context_dispatch (/usr/lib/x86_64-linux-gnu/libglib-2.= 0.so.0+) #38 in glib_pollfds_poll /util/main-loop.c:219:9 #39 in os_host_main_loop_wait /util/main-loop.c:242:5 #40 in main_loop_wait /util/main-loop.c:518:11 #41 in qemu_main_loop /softmmu/vl.c:1664:9 #42 in main /softmmu/main.c:52:5 #43 in __libc_start_main (/lib/x86_64-linux-gnu/libc.so.6+) #44 in _start (/build/i386-softmmu/qemu-system-i386+) 0x62500026800e is located 14 bytes inside of 138-byte region [0x625000268= 000,0x62500026808a) freed by thread T0 here: #0 in free (/build/i386-softmmu/qemu-system-i386+) #1 in qemu_vfree /util/oslib-posix.c:238:5 #2 in address_space_unmap /exec.c:3616:5 #3 in dma_memory_unmap /include/sysemu/dma.h:148:5 #4 in pci_dma_unmap /include/hw/pci/pci.h:839:5 #5 in net_tx_pkt_reset /hw/net/net_tx_pkt.c:453:9 #6 in e1000e_process_tx_desc /hw/net/e1000e_core.c:749:9 #7 in e1000e_start_xmit /hw/net/e1000e_core.c:934:9 #8 in e1000e_set_tctl /hw/net/e1000e_core.c:2431:9 #9 in e1000e_core_write /hw/net/e1000e_core.c:3265:9 #10 in e1000e_mmio_write /hw/net/e1000e.c:109:5 #11 in memory_region_write_accessor /memory.c:483:5 #12 in access_with_adjusted_size /memory.c:544:18 #13 in memory_region_dispatch_write /memory.c:1476:16 #14 in flatview_write_continue /exec.c:3146:23 #15 in flatview_write /exec.c:3186:14 #16 in address_space_write /exec.c:3280:18 #17 in address_space_rw /exec.c:3290:16 #18 in dma_memory_rw_relaxed /include/sysemu/dma.h:87:18 #19 in dma_memory_rw /include/sysemu/dma.h:113:12 #20 in pci_dma_rw /include/hw/pci/pci.h:789:5 #21 in pci_dma_write /include/hw/pci/pci.h:802:12 #22 in e1000e_write_to_rx_buffers /hw/net/e1000e_core.c:1412:9 #23 in e1000e_write_packet_to_guest /hw/net/e1000e_core.c:1582:21 #24 in e1000e_receive_iov /hw/net/e1000e_core.c:1709:9 #25 in e1000e_nc_receive_iov /hw/net/e1000e.c:213:12 #26 in net_tx_pkt_sendv /hw/net/net_tx_pkt.c:544:9 #27 in net_tx_pkt_send /hw/net/net_tx_pkt.c:620:9 #28 in net_tx_pkt_send_loopback /hw/net/net_tx_pkt.c:633:11 #29 in e1000e_tx_pkt_send /hw/net/e1000e_core.c:664:16 previously allocated by thread T0 here: #0 in posix_memalign (/build/i386-softmmu/qemu-system-i386+) #1 in qemu_try_memalign /util/oslib-posix.c:198:11 #2 in qemu_memalign /util/oslib-posix.c:214:27 #3 in address_space_map /exec.c:3558:25 #4 in dma_memory_map /include/sysemu/dma.h:138:9 #5 in pci_dma_map /include/hw/pci/pci.h:832:11 #6 in net_tx_pkt_add_raw_fragment /hw/net/net_tx_pkt.c:391:24 #7 in e1000e_process_tx_desc /hw/net/e1000e_core.c:731:14 #8 in e1000e_start_xmit /hw/net/e1000e_core.c:934:9 #9 in e1000e_set_tctl /hw/net/e1000e_core.c:2431:9 #10 in e1000e_core_write /hw/net/e1000e_core.c:3265:9 #11 in e1000e_mmio_write /hw/net/e1000e.c:109:5 #12 in memory_region_write_accessor /memory.c:483:5 #13 in access_with_adjusted_size /memory.c:544:18 #14 in memory_region_dispatch_write /memory.c:1476:16 #15 in flatview_write_continue /exec.c:3146:23 #16 in flatview_write /exec.c:3186:14 #17 in address_space_write /exec.c:3280:18 #18 in qtest_process_command /qtest.c:567:9 #19 in qtest_process_inbuf /qtest.c:710:9 #20 in qtest_read /qtest.c:722:5 #21 in qemu_chr_be_write_impl /chardev/char.c:188:9 #22 in qemu_chr_be_write /chardev/char.c:200:9 #23 in fd_chr_read /chardev/char-fd.c:68:9 #24 in qio_channel_fd_source_dispatch /io/channel-watch.c:84:12 #25 in g_main_context_dispatch (/usr/lib/x86_64-linux-gnu/libglib-2.= 0.so.0+) -Alex To manage notifications about this bug go to: https://bugs.launchpad.net/qemu/+bug/1886362/+subscriptions