Thanks for posting the resolution commits!
On Fri, Jun 17, 2022 at 7:37 AM Alexander Bulekov <
alxndr@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 <alxndr@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
> > > >
> >
>