Re: [syzbot] [ext4?] KASAN: use-after-free Read in __ext4_check_dir_entry (2)

[syzbot]

Hello,

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

e=vmci, major=10, minor=118)
[    7.595612][    T1] Initialized host personality
[    7.597261][    T1] usbcore: registered new interface driver rtsx_usb
[    7.599908][    T1] usbcore: registered new interface driver viperboard
[    7.603226][    T1] usbcore: registered new interface driver dln2
[    7.605088][    T1] usbcore: registered new interface driver pn533_usb
[    7.611678][    T1] nfcsim 0.2 initialized
[    7.613262][    T1] usbcore: registered new interface driver port100
[    7.614710][    T1] usbcore: registered new interface driver nfcmrvl
[    7.622445][    T1] Loading iSCSI transport class v2.0-870.
[    7.640265][    T1] virtio_scsi virtio0: 1/0/0 default/read/poll queues
[    7.650480][    T1] ------------[ cut here ]------------
[    7.651656][    T1] refcount_t: decrement hit 0; leaking memory.
[    7.653009][    T1] WARNING: CPU: 0 PID: 1 at lib/refcount.c:31 refcount_warn_saturate+0xfa/0x1d0
[    7.654567][    T1] Modules linked in:
[    7.655274][    T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc4-syzkaller-00039-g26770a717cac #0
[    7.656739][    T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
[    7.658271][    T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
[    7.659267][    T1] Code: b2 00 00 00 e8 57 49 f0 fc 5b 5d c3 cc cc cc cc e8 4b 49 f0 fc c6 05 4c 96 ec 0a 01 90 48 c7 c7 40 5d 1e 8c e8 c7 c5 b2 fc 90 <0f> 0b 90 90 eb d9 e8 2b 49 f0 fc c6 05 29 96 ec 0a 01 90 48 c7 c7
[    7.662662][    T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
[    7.663683][    T1] RAX: 6a628a5cb0f41700 RBX: ffff8881401ae78c RCX: ffff888016ac0000
[    7.665039][    T1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[    7.666341][    T1] RBP: 0000000000000004 R08: ffffffff81587fc2 R09: fffffbfff1c39b48
[    7.667553][    T1] R10: dffffc0000000000 R11: fffffbfff1c39b48 R12: ffffea0000858dc0
[    7.669559][    T1] R13: ffffea0000858dc8 R14: 1ffffd400010b1b9 R15: 0000000000000000
[    7.671059][    T1] FS:  0000000000000000(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
[    7.672346][    T1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    7.673289][    T1] CR2: ffff88823ffff000 CR3: 000000000e134000 CR4: 00000000003506f0
[    7.674581][    T1] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[    7.675775][    T1] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[    7.676905][    T1] Call Trace:
[    7.677523][    T1]  <TASK>
[    7.678310][    T1]  ? __warn+0x163/0x4e0
[    7.679650][    T1]  ? refcount_warn_saturate+0xfa/0x1d0
[    7.680990][    T1]  ? report_bug+0x2b3/0x500
[    7.681762][    T1]  ? refcount_warn_saturate+0xfa/0x1d0
[    7.682951][    T1]  ? handle_bug+0x3e/0x70
[    7.683875][    T1]  ? exc_invalid_op+0x1a/0x50
[    7.684757][    T1]  ? asm_exc_invalid_op+0x1a/0x20
[    7.686125][    T1]  ? __warn_printk+0x292/0x360
[    7.687439][    T1]  ? refcount_warn_saturate+0xfa/0x1d0
[    7.688770][    T1]  ? refcount_warn_saturate+0xf9/0x1d0
[    7.689853][    T1]  __free_pages_ok+0xc54/0xd80
[    7.690752][    T1]  make_alloc_exact+0xa3/0xf0
[    7.691436][    T1]  vring_alloc_queue_split+0x20a/0x600
[    7.692294][    T1]  ? __pfx_vring_alloc_queue_split+0x10/0x10
[    7.693145][    T1]  ? vp_find_vqs+0x4c/0x4e0
[    7.693988][    T1]  ? virtscsi_probe+0x3ea/0xf60
[    7.694794][    T1]  ? virtio_dev_probe+0x991/0xaf0
[    7.695541][    T1]  ? really_probe+0x2b8/0xad0
[    7.696410][    T1]  ? driver_probe_device+0x50/0x430
[    7.698097][    T1]  vring_create_virtqueue_split+0xc6/0x310
[    7.699062][    T1]  ? ret_from_fork+0x4b/0x80
[    7.699790][    T1]  ? __pfx_vring_create_virtqueue_split+0x10/0x10
[    7.700886][    T1]  vring_create_virtqueue+0xca/0x110
[    7.701895][    T1]  ? __pfx_vp_notify+0x10/0x10
[    7.703155][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    7.704118][    T1]  setup_vq+0xe9/0x2d0
[    7.704736][    T1]  ? __pfx_vp_notify+0x10/0x10
[    7.705391][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    7.706755][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    7.708116][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    7.708982][    T1]  vp_setup_vq+0xbf/0x330
[    7.709609][    T1]  ? __pfx_vp_config_changed+0x10/0x10
[    7.710370][    T1]  ? ioread16+0x2f/0x90
[    7.711005][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    7.711861][    T1]  vp_find_vqs_msix+0x8b2/0xc80
[    7.712762][    T1]  vp_find_vqs+0x4c/0x4e0
[    7.713463][    T1]  virtscsi_init+0x8db/0xd00
[    7.714142][    T1]  ? __pfx_virtscsi_init+0x10/0x10
[    7.715032][    T1]  ? __pfx_default_calc_sets+0x10/0x10
[    7.715928][    T1]  ? scsi_host_alloc+0xa57/0xea0
[    7.716710][    T1]  ? vp_get+0xfd/0x140
[    7.717535][    T1]  virtscsi_probe+0x3ea/0xf60
[    7.718252][    T1]  ? __pfx_virtscsi_probe+0x10/0x10
[    7.719062][    T1]  ? vm_set+0xdd/0x3a0
[    7.720396][    T1]  ? __pfx_vp_set_status+0x10/0x10
[    7.721514][    T1]  ? vp_set_status+0x1a/0x40
[    7.722164][    T1]  ? virtio_no_restricted_mem_acc+0x9/0x10
[    7.723108][    T1]  ? virtio_features_ok+0x10c/0x270
[    7.723887][    T1]  virtio_dev_probe+0x991/0xaf0
[    7.724709][    T1]  ? __pfx_virtio_dev_probe+0x10/0x10
[    7.725729][    T1]  really_probe+0x2b8/0xad0
[    7.726650][    T1]  __driver_probe_device+0x1a2/0x390
[    7.727503][    T1]  driver_probe_device+0x50/0x430
[    7.728243][    T1]  __driver_attach+0x45f/0x710
[    7.729022][    T1]  ? __pfx___driver_attach+0x10/0x10
[    7.729890][    T1]  bus_for_each_dev+0x239/0x2b0
[    7.730601][    T1]  ? __pfx___driver_attach+0x10/0x10
[    7.731421][    T1]  ? __pfx_bus_for_each_dev+0x10/0x10
[    7.732219][    T1]  ? do_raw_spin_unlock+0x13c/0x8b0
[    7.733309][    T1]  bus_add_driver+0x347/0x620
[    7.733992][    T1]  driver_register+0x23a/0x320
[    7.734667][    T1]  virtio_scsi_init+0x69/0xe0
[    7.735752][    T1]  ? __pfx_virtio_scsi_init+0x10/0x10
[    7.736692][    T1]  do_one_initcall+0x248/0x880
[    7.737732][    T1]  ? __pfx_virtio_scsi_init+0x10/0x10
[    7.738937][    T1]  ? __pfx_do_one_initcall+0x10/0x10
[    7.739803][    T1]  ? lockdep_hardirqs_on_prepare+0x43d/0x780
[    7.740876][    T1]  ? __pfx_parse_args+0x10/0x10
[    7.741838][    T1]  ? do_initcalls+0x1c/0x80
[    7.742731][    T1]  ? rcu_is_watching+0x15/0xb0
[    7.743513][    T1]  do_initcall_level+0x157/0x210
[    7.744299][    T1]  do_initcalls+0x3f/0x80
[    7.745007][    T1]  kernel_init_freeable+0x435/0x5d0
[    7.746216][    T1]  ? __pfx_kernel_init_freeable+0x10/0x10
[    7.747097][    T1]  ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[    7.748009][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.748782][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.749752][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.750548][    T1]  kernel_init+0x1d/0x2b0
[    7.751404][    T1]  ret_from_fork+0x4b/0x80
[    7.752121][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.752911][    T1]  ret_from_fork_asm+0x1a/0x30
[    7.753697][    T1]  </TASK>
[    7.754133][    T1] Kernel panic - not syncing: kernel: panic_on_warn set ...
[    7.755272][    T1] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.9.0-rc4-syzkaller-00039-g26770a717cac #0
[    7.757227][    T1] Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
[    7.759031][    T1] Call Trace:
[    7.759506][    T1]  <TASK>
[    7.759733][    T1]  dump_stack_lvl+0x241/0x360
[    7.759733][    T1]  ? __pfx_dump_stack_lvl+0x10/0x10
[    7.759733][    T1]  ? __pfx__printk+0x10/0x10
[    7.759733][    T1]  ? _printk+0xd5/0x120
[    7.759733][    T1]  ? vscnprintf+0x5d/0x90
[    7.759733][    T1]  panic+0x349/0x860
[    7.759733][    T1]  ? __warn+0x172/0x4e0
[    7.759733][    T1]  ? __pfx_panic+0x10/0x10
[    7.759733][    T1]  ? show_trace_log_lvl+0x4e6/0x520
[    7.759733][    T1]  ? ret_from_fork_asm+0x1a/0x30
[    7.759733][    T1]  __warn+0x346/0x4e0
[    7.759733][    T1]  ? refcount_warn_saturate+0xfa/0x1d0
[    7.759733][    T1]  report_bug+0x2b3/0x500
[    7.769119][    T1]  ? refcount_warn_saturate+0xfa/0x1d0
[    7.769119][    T1]  handle_bug+0x3e/0x70
[    7.769119][    T1]  exc_invalid_op+0x1a/0x50
[    7.769119][    T1]  asm_exc_invalid_op+0x1a/0x20
[    7.769119][    T1] RIP: 0010:refcount_warn_saturate+0xfa/0x1d0
[    7.769119][    T1] Code: b2 00 00 00 e8 57 49 f0 fc 5b 5d c3 cc cc cc cc e8 4b 49 f0 fc c6 05 4c 96 ec 0a 01 90 48 c7 c7 40 5d 1e 8c e8 c7 c5 b2 fc 90 <0f> 0b 90 90 eb d9 e8 2b 49 f0 fc c6 05 29 96 ec 0a 01 90 48 c7 c7
[    7.769119][    T1] RSP: 0000:ffffc90000066e18 EFLAGS: 00010246
[    7.769119][    T1] RAX: 6a628a5cb0f41700 RBX: ffff8881401ae78c RCX: ffff888016ac0000
[    7.769119][    T1] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
[    7.778978][    T1] RBP: 0000000000000004 R08: ffffffff81587fc2 R09: fffffbfff1c39b48
[    7.778978][    T1] R10: dffffc0000000000 R11: fffffbfff1c39b48 R12: ffffea0000858dc0
[    7.778978][    T1] R13: ffffea0000858dc8 R14: 1ffffd400010b1b9 R15: 0000000000000000
[    7.778978][    T1]  ? __warn_printk+0x292/0x360
[    7.778978][    T1]  ? refcount_warn_saturate+0xf9/0x1d0
[    7.778978][    T1]  __free_pages_ok+0xc54/0xd80
[    7.778978][    T1]  make_alloc_exact+0xa3/0xf0
[    7.778978][    T1]  vring_alloc_queue_split+0x20a/0x600
[    7.789051][    T1]  ? __pfx_vring_alloc_queue_split+0x10/0x10
[    7.789051][    T1]  ? vp_find_vqs+0x4c/0x4e0
[    7.789051][    T1]  ? virtscsi_probe+0x3ea/0xf60
[    7.789051][    T1]  ? virtio_dev_probe+0x991/0xaf0
[    7.789051][    T1]  ? really_probe+0x2b8/0xad0
[    7.789051][    T1]  ? driver_probe_device+0x50/0x430
[    7.789051][    T1]  vring_create_virtqueue_split+0xc6/0x310
[    7.789051][    T1]  ? ret_from_fork+0x4b/0x80
[    7.789051][    T1]  ? __pfx_vring_create_virtqueue_split+0x10/0x10
[    7.789051][    T1]  vring_create_virtqueue+0xca/0x110
[    7.789051][    T1]  ? __pfx_vp_notify+0x10/0x10
[    7.789051][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    7.798967][    T1]  setup_vq+0xe9/0x2d0
[    7.798967][    T1]  ? __pfx_vp_notify+0x10/0x10
[    7.798967][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    7.798967][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    7.798967][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    7.798967][    T1]  vp_setup_vq+0xbf/0x330
[    7.798967][    T1]  ? __pfx_vp_config_changed+0x10/0x10
[    7.798967][    T1]  ? ioread16+0x2f/0x90
[    7.798967][    T1]  ? __pfx_virtscsi_ctrl_done+0x10/0x10
[    7.798967][    T1]  vp_find_vqs_msix+0x8b2/0xc80
[    7.798967][    T1]  vp_find_vqs+0x4c/0x4e0
[    7.798967][    T1]  virtscsi_init+0x8db/0xd00
[    7.798967][    T1]  ? __pfx_virtscsi_init+0x10/0x10
[    7.809054][    T1]  ? __pfx_default_calc_sets+0x10/0x10
[    7.809054][    T1]  ? scsi_host_alloc+0xa57/0xea0
[    7.809054][    T1]  ? vp_get+0xfd/0x140
[    7.809054][    T1]  virtscsi_probe+0x3ea/0xf60
[    7.809054][    T1]  ? __pfx_virtscsi_probe+0x10/0x10
[    7.809054][    T1]  ? vm_set+0xdd/0x3a0
[    7.809054][    T1]  ? __pfx_vp_set_status+0x10/0x10
[    7.809054][    T1]  ? vp_set_status+0x1a/0x40
[    7.809054][    T1]  ? virtio_no_restricted_mem_acc+0x9/0x10
[    7.809054][    T1]  ? virtio_features_ok+0x10c/0x270
[    7.809054][    T1]  virtio_dev_probe+0x991/0xaf0
[    7.809054][    T1]  ? __pfx_virtio_dev_probe+0x10/0x10
[    7.818989][    T1]  really_probe+0x2b8/0xad0
[    7.818989][    T1]  __driver_probe_device+0x1a2/0x390
[    7.818989][    T1]  driver_probe_device+0x50/0x430
[    7.818989][    T1]  __driver_attach+0x45f/0x710
[    7.818989][    T1]  ? __pfx___driver_attach+0x10/0x10
[    7.818989][    T1]  bus_for_each_dev+0x239/0x2b0
[    7.818989][    T1]  ? __pfx___driver_attach+0x10/0x10
[    7.818989][    T1]  ? __pfx_bus_for_each_dev+0x10/0x10
[    7.818989][    T1]  ? do_raw_spin_unlock+0x13c/0x8b0
[    7.818989][    T1]  bus_add_driver+0x347/0x620
[    7.818989][    T1]  driver_register+0x23a/0x320
[    7.818989][    T1]  virtio_scsi_init+0x69/0xe0
[    7.818989][    T1]  ? __pfx_virtio_scsi_init+0x10/0x10
[    7.828983][    T1]  do_one_initcall+0x248/0x880
[    7.829040][    T1]  ? __pfx_virtio_scsi_init+0x10/0x10
[    7.829040][    T1]  ? __pfx_do_one_initcall+0x10/0x10
[    7.829040][    T1]  ? lockdep_hardirqs_on_prepare+0x43d/0x780
[    7.829040][    T1]  ? __pfx_parse_args+0x10/0x10
[    7.829040][    T1]  ? do_initcalls+0x1c/0x80
[    7.829040][    T1]  ? rcu_is_watching+0x15/0xb0
[    7.829040][    T1]  do_initcall_level+0x157/0x210
[    7.829040][    T1]  do_initcalls+0x3f/0x80
[    7.829040][    T1]  kernel_init_freeable+0x435/0x5d0
[    7.829040][    T1]  ? __pfx_kernel_init_freeable+0x10/0x10
[    7.829040][    T1]  ? __pfx_lockdep_hardirqs_on_prepare+0x10/0x10
[    7.829040][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.838961][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.838961][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.838961][    T1]  kernel_init+0x1d/0x2b0
[    7.838961][    T1]  ret_from_fork+0x4b/0x80
[    7.838961][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.838961][    T1]  ret_from_fork_asm+0x1a/0x30
[    7.838961][    T1]  </TASK>
[    7.838961][    T1] Kernel Offset: disabled
[    7.838961][    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-2/linux/gopath/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/syzkaller/jobs-2/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-2/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-build2122882332=/tmp/go-build -gno-record-gcc-switches'

git status (err=<nil>)
HEAD detached at de979bc20
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=de979bc20b2b73242b7d6fbbdf614a8cb4c574f4 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240509-085021'" "-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=de979bc20b2b73242b7d6fbbdf614a8cb4c574f4 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20240509-085021'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog
mkdir -p ./bin/linux_amd64
gcc -o ./bin/linux_amd64/syz-executor executor/executor.cc \
	-m64 -std=c++11 -I. -Iexecutor/_include -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=\"de979bc20b2b73242b7d6fbbdf614a8cb4c574f4\"


Error text is too large and was truncated, full error text is at:
https://syzkaller.appspot.com/x/error.txt?x=168a0e20980000


Tested on:

commit:         26770a71 jbd2: add prefix 'jbd2' for 'shrink_type'
git tree:       git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4.git dev
kernel config:  https://syzkaller.appspot.com/x/.config?x=f47e5e015c177e57
dashboard link: https://syzkaller.appspot.com/bug?extid=11af34d3c0711f233fd4
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

Note: no patches were applied.