The upstream fixes in https://gitlab.freedesktop.org/slirp/libslirp/-/commit/6489ebbc691f5d97221ad154d570a231e30fb369 and https://gitlab.freedesktop.org/slirp/libslirp/-/commit/cc20d9ac578aec5502dcb26557765d3e9433cb26 resolved the failure we were seeing in our internal test-case. Thanks!
On Tue, Jun 21, 2022 at 12:47 PM Patrick Venture <vent...@google.com> wrote: > > > On Fri, Jun 17, 2022 at 7:37 AM Alexander Bulekov <alx...@bu.edu> wrote: > >> On 220617 1217, Thomas Huth wrote: >> > On 16/06/2022 21.03, Alexander Bulekov wrote: >> > > On 220616 0930, Patrick Venture wrote: >> > > > On Thu, Jun 16, 2022 at 6:31 AM Alexander Bulekov <alx...@bu.edu> >> wrote: >> > > > >> > > > > Is this an --enable-sanitizers build? The virtual-device fuzzer >> catches >> > > > > >> > > > >> > > > Yeah - it should be reproducible with a sanitizers build from HEAD >> -- I can >> > > > try to get a manual instance going again without automation to try >> and >> > > > reproduce it. We're testing on v7.0.0 which is when we started >> seeing >> > > > this, I don't think we saw it in 6.2.0. >> > > >> > > Here are a few reproducers (run with --enable-sanitizers): >> > > >> > > This one complains about misalignments in ip_header, ipasfrag, qlink, >> > > ip... >> > > >> > > cat << EOF | ./qemu-system-i386 -display none -machine accel=qtest, >> -m \ >> > > 512M,slots=4,maxmem=0xffff000000000000 -machine q35 -nodefaults >> -device \ >> > > vmxnet3,netdev=net0 -netdev user,id=net0 -object \ >> > > memory-backend-ram,id=mem1,size=10M -device \ >> > > pc-dimm,id=nv1,memdev=mem1,addr=0xba19ff00000000 -object \ >> > > memory-backend-ram,id=mem2,size=10M -device \ >> > > pc-dimm,id=nv2,memdev=mem2,addr=0xbe53e14abaa00000 -object \ >> > > memory-backend-ram,id=mem3,size=10M -device \ >> > > pc-dimm,id=nv3,memdev=mem3,addr=0xfe0000e9cae00000 -object \ >> > > memory-backend-ram,id=mem4,size=10M -device \ >> > > pc-dimm,id=nv4,memdev=mem4,addr=0xf0f0f0f00000000 -qtest stdio >> > > outl 0xcf8 0x80000810 >> > > outl 0xcfc 0xe0000000 >> > > outl 0xcf8 0x80000814 >> > > outl 0xcfc 0xe0001000 >> > > outl 0xcf8 0x80000804 >> > > outw 0xcfc 0x06 >> > > write 0x3e 0x1 0x02 >> > > write 0x39 0x1 0x20 >> > > write 0x29 0x1 0x10 >> > > write 0x2c 0x1 0x0f >> > > write 0x2d 0x1 0x0f >> > > write 0x2e 0x1 0x0f >> > > write 0x2f 0x1 0x0f >> > > write 0xf0f0f0f00001012 0x1 0xfe >> > > write 0xf0f0f0f00001013 0x1 0xca >> > > write 0xf0f0f0f00001014 0x1 0xe9 >> > > write 0xf0f0f0f00001017 0x1 0xfe >> > > write 0xf0f0f0f0000103a 0x1 0x01 >> > > write 0xfe0000e9cafe0009 0x1 0x40 >> > > write 0xfe0000e9cafe0019 0x1 0x40 >> > > write 0x0 0x1 0xe1 >> > > write 0x1 0x1 0xfe >> > > write 0x2 0x1 0xbe >> > > write 0x3 0x1 0xba >> > > writel 0xe0001020 0xcafe0000 >> > > write 0xfe0000e9cafe0029 0x1 0x40 >> > > write 0xfe0000e9cafe0039 0x1 0x40 >> > > write 0xfe0000e9cafe0049 0x1 0x40 >> > > write 0xfe0000e9cafe0059 0x1 0x40 >> > > write 0x1f65190b 0x1 0x08 >> > > write 0x1f65190d 0x1 0x46 >> > > write 0x1f65190e 0x1 0x03 >> > > write 0x1f651915 0x1 0x01 >> > > write 0xfe0000e9cafe0069 0x1 0x40 >> > > write 0xfe0000e9cafe0079 0x1 0x40 >> > > write 0xfe0000e9cafe0089 0x1 0x40 >> > > write 0xfe0000e9cafe0099 0x1 0x40 >> > > write 0xfe0000e9cafe009d 0x1 0x10 >> > > write 0xfe0000e9cafe00a0 0x1 0xff >> > > write 0xfe0000e9cafe00a1 0x1 0x18 >> > > write 0xfe0000e9cafe00a2 0x1 0x65 >> > > write 0xfe0000e9cafe00a3 0x1 0x1f >> > > write 0xfe0000e9cafe00a9 0x1 0x40 >> > > write 0xfe0000e9cafe00ad 0x1 0x1c >> > > write 0xe0000602 0x1 0x00 >> > > EOF >> > > >> > > This one complains about misalignments in ip6_header, ip6_hdrctl... >> > > >> > > cat << EOF | ./qemu-system-i386 -display none -machine accel=qtest, >> -m \ >> > > 512M,slots=1,maxmem=0xffff000000000000 -machine q35 -nodefaults >> -device \ >> > > vmxnet3,netdev=net0 -netdev user,id=net0 -object \ >> > > memory-backend-ram,id=mem1,size=4M -device \ >> > > pc-dimm,id=nv1,memdev=mem1,addr=0x1dd860000000000 -qtest stdio >> > > outl 0xcf8 0x80000810 >> > > outl 0xcfc 0xe0000000 >> > > outl 0xcf8 0x80000814 >> > > outl 0xcfc 0xe0001000 >> > > outl 0xcf8 0x80000804 >> > > outw 0xcfc 0x06 >> > > write 0x0 0x1 0xe1 >> > > write 0x1 0x1 0xfe >> > > write 0x2 0x1 0xbe >> > > write 0x3 0x1 0xba >> > > write 0x3e 0x1 0x01 >> > > write 0x39 0x1 0x01 >> > > write 0x28 0x1 0x01 >> > > write 0x29 0x1 0x01 >> > > write 0x2d 0x1 0x86 >> > > write 0x2e 0x1 0xdd >> > > write 0x2f 0x1 0x01 >> > > write 0x1dd860000000112 0x1 0x10 >> > > write 0x1dd86000000013c 0x1 0x02 >> > > writel 0xe0001020 0xcafe0000 >> > > write 0x1009 0x1 0x40 >> > > write 0x100c 0x1 0x86 >> > > write 0x100d 0x1 0xdd >> > > write 0x1011 0x1 0x10 >> > > write 0x1019 0x1 0x7e >> > > write 0x101d 0x1 0x10 >> > > write 0x4d56 0x1 0x02 >> > > write 0xe0000603 0x1 0x00 >> > > EOF >> > >> > Could you please open bugs on >> > https://gitlab.freedesktop.org/slirp/libslirp/-/issues so that this >> > information does not get lost? >> >> Done: >> https://gitlab.freedesktop.org/slirp/libslirp/-/issues/62 >> https://gitlab.freedesktop.org/slirp/libslirp/-/issues/63 > > > Thank you! > >> >> >> -Alex >> >> > >> > Thomas >> > >> > > > >> > > > > these periodically while fuzzing network-devices. However I don't >> think >> > > > > OSS-Fuzz creates reports for them for some reason. I can create >> qtest >> > > > > reproducers, if that is useful. >> > > > > -Alex >> > > > > >> > > > > On 220615 0942, Patrick Venture wrote: >> > > > > > Hey - I wanted to ask if someone else has seen this or has >> suggestions on >> > > > > > how to fix it in libslirp / qemu. >> > > > > > >> > > > > > libslirp version: 3ad1710a96678fe79066b1469cead4058713a1d9 >> > > > > > >> > > > > > The blow is line: >> > > > > > >> > > > > >> https://gitlab.freedesktop.org/slirp/libslirp/-/blob/master/src/tcp_input.c#L310 >> > > > > > >> > > > > > I0614 13:44:44.304087 2040 bytestream.cc:22] QEMU: >> > > > > > third_party/libslirp/src/tcp_input.c:310:56: runtime error: >> member access >> > > > > > within misaligned address 0xffff9a4000f4 for type 'struct >> qlink', which >> > > > > > requires 8 byte alignment >> > > > > > I0614 13:44:44.304156 2040 bytestream.cc:22] QEMU: >> 0xffff9a4000f4: >> > > > > note: >> > > > > > pointer points here >> > > > > > I0614 13:44:44.304184 2040 bytestream.cc:22] QEMU: 00 00 >> 00 00 00 00 >> > > > > > 00 02 20 02 0a 00 00 01 42 01 0a 00 02 02 42 01 0a 00 00 01 >> 86 dd 60 >> > > > > 02 >> > > > > > dd 79 >> > > > > > I0614 13:44:44.304204 2040 bytestream.cc:22] QEMU: >> ^ >> > > > > > I0614 13:44:44.641173 2040 bytestream.cc:22] QEMU: #0 >> > > > > 0xaaaacbe34bd8 >> > > > > > in tcp_input third_party/libslirp/src/tcp_input.c:310:56 >> > > > > > I0614 13:44:44.641239 2040 bytestream.cc:22] QEMU: #1 >> > > > > 0xaaaacbe22a94 >> > > > > > in ip6_input third_party/libslirp/src/ip6_input.c:74:9 >> > > > > > I0614 13:44:44.641262 2040 bytestream.cc:22] QEMU: #2 >> > > > > 0xaaaacbe0bbbc >> > > > > > in slirp_input third_party/libslirp/src/slirp.c:1169:13 >> > > > > > I0614 13:44:44.641280 2040 bytestream.cc:22] QEMU: #3 >> > > > > 0xaaaacbd55f6c >> > > > > > in net_slirp_receive third_party/qemu/net/slirp.c:136:5 >> > > > > > I0614 13:44:44.641296 2040 bytestream.cc:22] QEMU: #4 >> > > > > 0xaaaacbd4e77c >> > > > > > in nc_sendv_compat third_party/qemu/net/net.c >> > > > > > I0614 13:44:44.641323 2040 bytestream.cc:22] QEMU: #5 >> > > > > 0xaaaacbd4e77c >> > > > > > in qemu_deliver_packet_iov third_party/qemu/net/net.c:850:15 >> > > > > > I0614 13:44:44.641342 2040 bytestream.cc:22] QEMU: #6 >> > > > > 0xaaaacbd50bfc >> > > > > > in qemu_net_queue_deliver_iov >> third_party/qemu/net/queue.c:179:11 >> > > > > > I0614 13:44:44.641359 2040 bytestream.cc:22] QEMU: #7 >> > > > > 0xaaaacbd50bfc >> > > > > > in qemu_net_queue_send_iov third_party/qemu/net/queue.c:246:11 >> > > > > > I0614 13:44:44.641382 2040 bytestream.cc:22] QEMU: #8 >> > > > > 0xaaaacbd4a88c >> > > > > > in qemu_sendv_packet_async third_party/qemu/net/net.c:891:12 >> > > > > > I0614 13:44:44.641396 2040 bytestream.cc:22] QEMU: #9 >> > > > > 0xaaaacacb1de0 >> > > > > > in virtio_net_flush_tx >> third_party/qemu/hw/net/virtio-net.c:2586:15 >> > > > > > I0614 13:44:44.641416 2040 bytestream.cc:22] QEMU: #10 >> > > > > > 0xaaaacacb1580 in virtio_net_tx_bh >> > > > > > third_party/qemu/hw/net/virtio-net.c:2703:11 >> > > > > > I0614 13:44:44.641438 2040 bytestream.cc:22] QEMU: #11 >> > > > > > 0xaaaacc2bcf64 in aio_bh_call >> third_party/qemu/util/async.c:142:5 >> > > > > > I0614 13:44:44.641463 2040 bytestream.cc:22] QEMU: #12 >> > > > > > 0xaaaacc2bcf64 in aio_bh_poll >> third_party/qemu/util/async.c:170:13 >> > > > > > I0614 13:44:44.641477 2040 bytestream.cc:22] QEMU: #13 >> > > > > > 0xaaaacc2b8f70 in aio_dispatch >> third_party/qemu/util/aio-posix.c:420:5 >> > > > > > I0614 13:44:44.641495 2040 bytestream.cc:22] QEMU: #14 >> > > > > > 0xaaaacc2bf120 in aio_ctx_dispatch >> third_party/qemu/util/async.c:312:5 >> > > > > > I0614 13:44:44.641510 2040 bytestream.cc:22] QEMU: #15 >> > > > > > 0xaaaacc3a7690 in g_main_dispatch >> third_party/glib/glib/gmain.c:3417:27 >> > > > > > I0614 13:44:44.641525 2040 bytestream.cc:22] QEMU: #16 >> > > > > > 0xaaaacc3a7690 in g_main_context_dispatch >> > > > > > third_party/glib/glib/gmain.c:4135:7 >> > > > > > I0614 13:44:44.641546 2040 bytestream.cc:22] QEMU: #17 >> > > > > > 0xaaaacc2de3ec in glib_pollfds_poll >> > > > > third_party/qemu/util/main-loop.c:232:9 >> > > > > > I0614 13:44:44.641562 2040 bytestream.cc:22] QEMU: #18 >> > > > > > 0xaaaacc2de3ec in os_host_main_loop_wait >> > > > > > third_party/qemu/util/main-loop.c:255:5 >> > > > > > I0614 13:44:44.641580 2040 bytestream.cc:22] QEMU: #19 >> > > > > > 0xaaaacc2de3ec in main_loop_wait >> third_party/qemu/util/main-loop.c:531:11 >> > > > > > I0614 13:44:44.641598 2040 bytestream.cc:22] QEMU: #20 >> > > > > > 0xaaaacbd82798 in qemu_main_loop >> > > > > third_party/qemu/softmmu/runstate.c:727:9 >> > > > > > I0614 13:44:44.641612 2040 bytestream.cc:22] QEMU: #21 >> > > > > > 0xaaaacadacb5c in main >> > > > > > >> > > > > > Patrick >> > > > > >> > > >> > >> >
