Re: [syzbot] [io-uring?] kernel BUG in __io_remove_buffers

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

perboard
[    7.926982][    T1] usbcore: registered new interface driver dln2
[    7.928671][    T1] usbcore: registered new interface driver pn533_usb
[    7.935981][    T1] nfcsim 0.2 initialized
[    7.937582][    T1] usbcore: registered new interface driver port100
[    7.939440][    T1] usbcore: registered new interface driver nfcmrvl
[    7.947210][    T1] Loading iSCSI transport class v2.0-870.
[    7.968081][    T1] virtio_scsi virtio0: 1/0/0 default/read/poll queues
[    7.978141][    T1] ------------[ cut here ]------------
[    7.979719][    T1] refcount_t: decrement hit 0; leaking memory.
[    7.981758][    T1] WARNING: CPU: 0 PID: 1 at lib/refcount.c:31 refcount_warn_saturate+0xfa/0x1d0
[    7.984304][    T1] Modules linked in:
[    7.985206][    T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc2-syzkaller-00062-g25d658afbb9f #0
[    7.987566][    T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
[    7.989580][    T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
[    7.991289][    T1] Code: b2 00 00 00 e8 67 f3 e9 fc 5b 5d c3 cc cc cc cc e8 5b f3 e9 fc c6 05 73 24 e8 0a 01 90 48 c7 c7 40 34 1f 8c e8 67 8e ac fc 90 <0f> 0b 90 90 eb d9 e8 3b f3 e9 fc c6 05 50 24 e8 0a 01 90 48 c7 c7
[    7.995319][    T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
[    7.996425][    T1] RAX: 4d5c6abb0d962900 RBX: ffff8880215f782c RCX: ffff8880166d0000
[    7.998305][    T1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[    7.999479][    T1] RBP: 0000000000000004 R08: ffffffff8157ffc2 R09: fffffbfff1c39af8
[    8.001772][    T1] R10: dffffc0000000000 R11: fffffbfff1c39af8 R12: ffffea000502cdc0
[    8.004141][    T1] R13: ffffea000502cdc8 R14: 1ffffd4000a059b9 R15: 0000000000000000
[    8.006063][    T1] FS:  0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
[    8.007727][    T1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    8.009976][    T1] CR2: ffff88823ffff000 CR3: 000000000e134000 CR4: 00000000003506f0
[    8.011700][    T1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    8.013384][    T1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[    8.015782][    T1] Call Trace:
[    8.016883][    T1]  <TASK>
[    8.017827][    T1]  ? __warn+0x163/0x4e0
[    8.019345][    T1]  ? refcount_warn_saturate+0xfa/0x1d0
[    8.021058][    T1]  ? report_bug+0x2b3/0x500
[    8.022280][    T1]  ? refcount_warn_saturate+0xfa/0x1d0
[    8.024027][    T1]  ? handle_bug+0x3e/0x70
[    8.025284][    T1]  ? exc_invalid_op+0x1a/0x50
[    8.026551][    T1]  ? asm_exc_invalid_op+0x1a/0x20
[    8.027878][    T1]  ? __warn_printk+0x292/0x360
[    8.029272][    T1]  ? refcount_warn_saturate+0xfa/0x1d0
[    8.030730][    T1]  ? refcount_warn_saturate+0xf9/0x1d0
[    8.032217][    T1]  __free_pages_ok+0xc60/0xd90
[    8.033265][    T1]  make_alloc_exact+0xa3/0xf0
[    8.034312][    T1]  vring_alloc_queue_split+0x20a/0x600
[    8.035607][    T1]  ? __pfx_vring_alloc_queue_split+0x10/0x10
[    8.036997][    T1]  ? vp_find_vqs+0x4c/0x4e0
[    8.038142][    T1]  ? virtscsi_probe+0x3ea/0xf60
[    8.039207][    T1]  ? virtio_dev_probe+0x991/0xaf0
[    8.040304][    T1]  ? really_probe+0x2b8/0xad0
[    8.041140][    T1]  ? driver_probe_device+0x50/0x430
[    8.042068][    T1]  vring_create_virtqueue_split+0xc6/0x310
[    8.042973][    T1]  ? ret_from_fork+0x4b/0x80
[    8.044035][    T1]  ? __pfx_vring_create_virtqueue_split+0x10/0x10
[    8.045362][    T1]  vring_create_virtqueue+0xca/0x110
[    8.046384][    T1]  ? __pfx_vp_notify+0x10/0x10
[    8.047405][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    8.048436][    T1]  setup_vq+0xe9/0x2d0
[    8.049363][    T1]  ? __pfx_vp_notify+0x10/0x10
[    8.050238][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    8.051200][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    8.053099][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    8.054362][    T1]  vp_setup_vq+0xbf/0x330
[    8.055098][    T1]  ? __pfx_vp_config_changed+0x10/0x10
[    8.056155][    T1]  ? ioread16+0x2f/0x90
[    8.057127][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    8.057929][    T1]  vp_find_vqs_msix+0x8b2/0xc80
[    8.058857][    T1]  vp_find_vqs+0x4c/0x4e0
[    8.059767][    T1]  virtscsi_init+0x8db/0xd00
[    8.060631][    T1]  ? __pfx_virtscsi_init+0x10/0x10
[    8.061568][    T1]  ? __pfx_default_calc_sets+0x10/0x10
[    8.062509][    T1]  ? scsi_host_alloc+0xa57/0xea0
[    8.063697][    T1]  ? vp_get+0xfd/0x140
[    8.064484][    T1]  virtscsi_probe+0x3ea/0xf60
[    8.065484][    T1]  ? __pfx_virtscsi_probe+0x10/0x10
[    8.066504][    T1]  ? kernfs_add_one+0x156/0x8b0
[    8.067579][    T1]  ? virtio_no_restricted_mem_acc+0x9/0x10
[    8.069445][    T1]  ? virtio_features_ok+0x10c/0x270
[    8.070687][    T1]  virtio_dev_probe+0x991/0xaf0
[    8.071903][    T1]  ? __pfx_virtio_dev_probe+0x10/0x10
[    8.073120][    T1]  really_probe+0x2b8/0xad0
[    8.074086][    T1]  __driver_probe_device+0x1a2/0x390
[    8.075198][    T1]  driver_probe_device+0x50/0x430
[    8.076215][    T1]  __driver_attach+0x45f/0x710
[    8.077779][    T1]  ? __pfx___driver_attach+0x10/0x10
[    8.078838][    T1]  bus_for_each_dev+0x239/0x2b0
[    8.080219][    T1]  ? __pfx___driver_attach+0x10/0x10
[    8.081427][    T1]  ? __pfx_bus_for_each_dev+0x10/0x10
[    8.082648][    T1]  ? do_raw_spin_unlock+0x13c/0x8b0
[    8.084332][    T1]  bus_add_driver+0x347/0x620
[    8.085542][    T1]  driver_register+0x23a/0x320
[    8.086355][    T1]  ? __pfx_virtio_scsi_init+0x10/0x10
[    8.087517][    T1]  virtio_scsi_init+0x65/0xe0
[    8.088253][    T1]  ? __pfx_virtio_scsi_init+0x10/0x10
[    8.089537][    T1]  do_one_initcall+0x248/0x880
[    8.090403][    T1]  ? __pfx_virtio_scsi_init+0x10/0x10
[    8.091597][    T1]  ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[    8.093212][    T1]  ? __pfx_do_one_initcall+0x10/0x10
[    8.094289][    T1]  ? __pfx_parse_args+0x10/0x10
[    8.095147][    T1]  ? do_initcalls+0x1c/0x80
[    8.096320][    T1]  ? rcu_is_watching+0x15/0xb0
[    8.097696][    T1]  do_initcall_level+0x157/0x210
[    8.098851][    T1]  do_initcalls+0x3f/0x80
[    8.099669][    T1]  kernel_init_freeable+0x435/0x5d0
[    8.100419][    T1]  ? __pfx_kernel_init_freeable+0x10/0x10
[    8.101767][    T1]  ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[    8.103417][    T1]  ? __pfx_kernel_init+0x10/0x10
[    8.104551][    T1]  ? __pfx_kernel_init+0x10/0x10
[    8.105480][    T1]  ? __pfx_kernel_init+0x10/0x10
[    8.106672][    T1]  kernel_init+0x1d/0x2b0
[    8.107961][    T1]  ret_from_fork+0x4b/0x80
[    8.108943][    T1]  ? __pfx_kernel_init+0x10/0x10
[    8.109758][    T1]  ret_from_fork_asm+0x1a/0x30
[    8.111216][    T1]  </TASK>
[    8.111818][    T1] Kernel panic - not syncing: kernel: panic_on_warn set ...
[    8.113547][    T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc2-syzkaller-00062-g25d658afbb9f #0
[    8.114525][    T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
[    8.114525][    T1] Call Trace:
[    8.114525][    T1]  <TASK>
[    8.114525][    T1]  dump_stack_lvl+0x241/0x360
[    8.114525][    T1]  ? __pfx_dump_stack_lvl+0x10/0x10
[    8.114525][    T1]  ? __pfx__printk+0x10/0x10
[    8.114525][    T1]  ? _printk+0xd5/0x120
[    8.114525][    T1]  ? vscnprintf+0x5d/0x90
[    8.114525][    T1]  panic+0x349/0x860
[    8.124011][    T1]  ? __warn+0x172/0x4e0
[    8.124011][    T1]  ? __pfx_panic+0x10/0x10
[    8.124011][    T1]  ? show_trace_log_lvl+0x4e6/0x520
[    8.124011][    T1]  ? ret_from_fork_asm+0x1a/0x30
[    8.124011][    T1]  __warn+0x346/0x4e0
[    8.124011][    T1]  ? refcount_warn_saturate+0xfa/0x1d0
[    8.124011][    T1]  report_bug+0x2b3/0x500
[    8.124011][    T1]  ? refcount_warn_saturate+0xfa/0x1d0
[    8.124011][    T1]  handle_bug+0x3e/0x70
[    8.133902][    T1]  exc_invalid_op+0x1a/0x50
[    8.133902][    T1]  asm_exc_invalid_op+0x1a/0x20
[    8.133902][    T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
[    8.133902][    T1] Code: b2 00 00 00 e8 67 f3 e9 fc 5b 5d c3 cc cc cc cc e8 5b f3 e9 fc c6 05 73 24 e8 0a 01 90 48 c7 c7 40 34 1f 8c e8 67 8e ac fc 90 <0f> 0b 90 90 eb d9 e8 3b f3 e9 fc c6 05 50 24 e8 0a 01 90 48 c7 c7
[    8.133902][    T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
[    8.133902][    T1] RAX: 4d5c6abb0d962900 RBX: ffff8880215f782c RCX: ffff8880166d0000
[    8.143997][    T1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[    8.143997][    T1] RBP: 0000000000000004 R08: ffffffff8157ffc2 R09: fffffbfff1c39af8
[    8.143997][    T1] R10: dffffc0000000000 R11: fffffbfff1c39af8 R12: ffffea000502cdc0
[    8.143997][    T1] R13: ffffea000502cdc8 R14: 1ffffd4000a059b9 R15: 0000000000000000
[    8.143997][    T1]  ? __warn_printk+0x292/0x360
[    8.143997][    T1]  ? refcount_warn_saturate+0xf9/0x1d0
[    8.143997][    T1]  __free_pages_ok+0xc60/0xd90
[    8.143997][    T1]  make_alloc_exact+0xa3/0xf0
[    8.153906][    T1]  vring_alloc_queue_split+0x20a/0x600
[    8.153906][    T1]  ? __pfx_vring_alloc_queue_split+0x10/0x10
[    8.153906][    T1]  ? vp_find_vqs+0x4c/0x4e0
[    8.153906][    T1]  ? virtscsi_probe+0x3ea/0xf60
[    8.153906][    T1]  ? virtio_dev_probe+0x991/0xaf0
[    8.153906][    T1]  ? really_probe+0x2b8/0xad0
[    8.153906][    T1]  ? driver_probe_device+0x50/0x430
[    8.153906][    T1]  vring_create_virtqueue_split+0xc6/0x310
[    8.153906][    T1]  ? ret_from_fork+0x4b/0x80
[    8.153906][    T1]  ? __pfx_vring_create_virtqueue_split+0x10/0x10
[    8.163970][    T1]  vring_create_virtqueue+0xca/0x110
[    8.163970][    T1]  ? __pfx_vp_notify+0x10/0x10
[    8.163970][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    8.163970][    T1]  setup_vq+0xe9/0x2d0
[    8.163970][    T1]  ? __pfx_vp_notify+0x10/0x10
[    8.163970][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    8.163970][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    8.163970][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    8.173902][    T1]  vp_setup_vq+0xbf/0x330
[    8.173902][    T1]  ? __pfx_vp_config_changed+0x10/0x10
[    8.173902][    T1]  ? ioread16+0x2f/0x90
[    8.173902][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    8.173902][    T1]  vp_find_vqs_msix+0x8b2/0xc80
[    8.173902][    T1]  vp_find_vqs+0x4c/0x4e0
[    8.173902][    T1]  virtscsi_init+0x8db/0xd00
[    8.173902][    T1]  ? __pfx_virtscsi_init+0x10/0x10
[    8.173902][    T1]  ? __pfx_default_calc_sets+0x10/0x10
[    8.183960][    T1]  ? scsi_host_alloc+0xa57/0xea0
[    8.183960][    T1]  ? vp_get+0xfd/0x140
[    8.183960][    T1]  virtscsi_probe+0x3ea/0xf60
[    8.183960][    T1]  ? __pfx_virtscsi_probe+0x10/0x10
[    8.183960][    T1]  ? kernfs_add_one+0x156/0x8b0
[    8.183960][    T1]  ? virtio_no_restricted_mem_acc+0x9/0x10
[    8.183960][    T1]  ? virtio_features_ok+0x10c/0x270
[    8.193962][    T1]  virtio_dev_probe+0x991/0xaf0
[    8.193962][    T1]  ? __pfx_virtio_dev_probe+0x10/0x10
[    8.193962][    T1]  really_probe+0x2b8/0xad0
[    8.193962][    T1]  __driver_probe_device+0x1a2/0x390
[    8.193962][    T1]  driver_probe_device+0x50/0x430
[    8.193962][    T1]  __driver_attach+0x45f/0x710
[    8.193962][    T1]  ? __pfx___driver_attach+0x10/0x10
[    8.193962][    T1]  bus_for_each_dev+0x239/0x2b0
[    8.204004][    T1]  ? __pfx___driver_attach+0x10/0x10
[    8.204004][    T1]  ? __pfx_bus_for_each_dev+0x10/0x10
[    8.204004][    T1]  ? do_raw_spin_unlock+0x13c/0x8b0
[    8.204004][    T1]  bus_add_driver+0x347/0x620
[    8.204004][    T1]  driver_register+0x23a/0x320
[    8.204004][    T1]  ? __pfx_virtio_scsi_init+0x10/0x10
[    8.204004][    T1]  virtio_scsi_init+0x65/0xe0
[    8.204004][    T1]  ? __pfx_virtio_scsi_init+0x10/0x10
[    8.213923][    T1]  do_one_initcall+0x248/0x880
[    8.213923][    T1]  ? __pfx_virtio_scsi_init+0x10/0x10
[    8.213923][    T1]  ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[    8.213923][    T1]  ? __pfx_do_one_initcall+0x10/0x10
[    8.213923][    T1]  ? __pfx_parse_args+0x10/0x10
[    8.213923][    T1]  ? do_initcalls+0x1c/0x80
[    8.213923][    T1]  ? rcu_is_watching+0x15/0xb0
[    8.223993][    T1]  do_initcall_level+0x157/0x210
[    8.223993][    T1]  do_initcalls+0x3f/0x80
[    8.223993][    T1]  kernel_init_freeable+0x435/0x5d0
[    8.223993][    T1]  ? __pfx_kernel_init_freeable+0x10/0x10
[    8.223993][    T1]  ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[    8.223993][    T1]  ? __pfx_kernel_init+0x10/0x10
[    8.223993][    T1]  ? __pfx_kernel_init+0x10/0x10
[    8.233955][    T1]  ? __pfx_kernel_init+0x10/0x10
[    8.233955][    T1]  kernel_init+0x1d/0x2b0
[    8.233955][    T1]  ret_from_fork+0x4b/0x80
[    8.233955][    T1]  ? __pfx_kernel_init+0x10/0x10
[    8.233955][    T1]  ret_from_fork_asm+0x1a/0x30
[    8.233955][    T1]  </TASK>
[    8.233955][    T1] Kernel Offset: disabled
[    8.233955][    T1] Rebooting in 86400 seconds..


syzkaller build log:
go env (err=<nil>)
GO111MODULE='auto'
GOARCH='amd64'
GOBIN=''
GOCACHE='/syzkaller/.cache/go-build'
GOENV='/syzkaller/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMODCACHE='/syzkaller/jobs/linux/gopath/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/syzkaller/jobs/linux/gopath'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/local/go'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.21.4'
GCCGO='gccgo'
GOAMD64='v1'
AR='ar'
CC='gcc'
CXX='g++'
CGO_ENABLED='1'
GOMOD='/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/go.mod'
GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build1588439291=/tmp/go-build -gno-record-gcc-switches'

git status (err=<nil>)
HEAD detached at 6baf50694
nothing to commit, working tree clean


tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
go list -f '{{.Stale}}' ./sys/syz-sysgen | grep -q false || go install ./sys/syz-sysgen
make .descriptions
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
bin/syz-sysgen
touch .descriptions
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=6baf506947ba27ed9ce775cf9351cb0886166083 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240329-215124'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-fuzzer github.com/google/syzkaller/syz-fuzzer
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=6baf506947ba27ed9ce775cf9351cb0886166083 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240329-215124'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=6baf506947ba27ed9ce775cf9351cb0886166083 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240329-215124'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-stress github.com/google/syzkaller/tools/syz-stress
mkdir -p ./bin/linux_amd64
gcc -o ./bin/linux_amd64/syz-executor executor/executor.cc \
	-m64 -O2 -pthread -Wall -Werror -Wparentheses -Wunused-const-variable -Wframe-larger-than=16384 -Wno-stringop-overflow -Wno-array-bounds -Wno-format-overflow -Wno-unused-but-set-variable -Wno-unused-command-line-argument -static-pie -fpermissive -w -DGOOS_linux=1 -DGOARCH_amd64=1 \
	-DHOSTGOOS_linux=1 -DGIT_REVISION=\"6baf506947ba27ed9ce775cf9351cb0886166083\"


Error text is too large and was truncated, full error text is at:
https://syzkaller.appspot.com/x/error.txt?x=102c48de180000


Tested on:

commit:         25d658af io_uring/kbuf: remove dead define
git tree:       git://git.kernel.dk/linux.git for-6.10/io_uring
kernel config:  https://syzkaller.appspot.com/x/.config?x=51cdcd4a8f332569
dashboard link: https://syzkaller.appspot.com/bug?extid=beb5226eef6218124e9d
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.