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From: syzbot <syzbot+ecbb1750082f7528b507@syzkaller.appspotmail.com>
To: hdanton@sina.com, linux-kernel@vger.kernel.org,
	 syzkaller-bugs@googlegroups.com
Subject: Re: [syzbot] KASAN: slab-use-after-free Read in vhci_send_cmd_submit
Date: Fri, 21 Aug 2026 17:54:02 -0700	[thread overview]
Message-ID: <6a88f32a.dbb3a75c.13dd47.0024.GAE@google.com> (raw)
In-Reply-To: <20260822003021.1378-1-hdanton@sina.com>

Hello,

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

 max_idle_ns: 440795210424 ns
[    5.995352][    T1] clocksource: Switched to clocksource tsc
[    6.007879][   T81] kworker/u33:1 (81) used greatest stack depth: 26904 bytes left
[    6.062555][    T1] Initialise system trusted keyrings
[    6.068264][    T1] workingset: timestamp_bits=40 (anon: 35) max_order=20 bucket_order=0 (anon: 0)
[    6.084373][    T1] DLM installed
[    6.093346][    T1] squashfs: version 4.0 (2009/01/31) Phillip Lougher
[    6.107861][    T1] NFS: Registering the id_resolver key type
[    6.111646][    T1] Key type id_resolver registered
[    6.114786][    T1] Key type id_legacy registered
[    6.119374][    T1] nfs4filelayout_init: NFSv4 File Layout Driver Registering...
[    6.125128][    T1] nfs4flexfilelayout_init: NFSv4 Flexfile Layout Driver Registering...
[    6.134956][    T1] smbdirect: subsystem loading...
[    6.142804][    T1] smbdirect: subsystem loaded
[    6.170761][    T1] Key type cifs.spnego registered
[    6.174632][    T1] Key type cifs.idmap registered
[    6.182165][    T1] ntfs3: Enabled Linux POSIX ACLs support
[    6.186222][    T1] ntfs3: Read-only LZX/Xpress compression included
[    6.190956][    T1] jffs2: version 2.2. (NAND) (SUMMARY)  © 2001-2006 Red Hat, Inc.
[    6.199740][    T1] romfs: ROMFS MTD (C) 2007 Red Hat, Inc.
[    6.204013][    T1] QNX4 filesystem 0.2.3 registered.
[    6.207716][    T1] qnx6: QNX6 filesystem 1.0.0 registered.
[    6.213095][    T1] fuse: init (API version 7.45)
[    6.219370][    T1] orangefs_debugfs_init: called with debug mask: :none: :0:
[    6.226020][    T1] orangefs_init: module version upstream loaded
[    6.230617][    T1] JFS: nTxBlock = 8192, nTxLock = 65536
[    6.246493][    T1] SGI XFS with ACLs, security attributes, realtime, scrub, repair, quota, no debug enabled
[    6.258932][    T1] 9p: Installing v9fs 9p2000 file system support
[    6.263234][    T1] NILFS version 2 loaded
[    6.265499][    T1] befs: version: 0.9.3
[    6.268610][    T1] ocfs2: Registered cluster interface o2cb
[    6.273749][    T1] ocfs2: Registered cluster interface user
[    6.278040][    T1] OCFS2 User DLM kernel interface loaded
[    6.293970][    T1] gfs2: GFS2 installed
[    6.308103][    T1] ceph: loaded (mds proto 32)
[    6.323721][    T1] NET: Registered PF_ALG protocol family
[    6.327858][    T1] async_tx: api initialized (async)
[    6.331276][    T1] Key type asymmetric registered
[    6.334605][    T1] Asymmetric key parser 'x509' registered
[    6.338691][    T1] Asymmetric key parser 'pkcs8' registered
[    6.342508][    T1] Key type pkcs7_test registered
[    6.346832][    T1] Block layer SCSI generic (bsg) driver version 0.4 loaded (major 239)
[    6.354523][    T1] io scheduler mq-deadline registered
[    6.358129][    T1] io scheduler kyber registered
[    6.361302][    T1] io scheduler bfq registered
[    6.402053][    T1] ACPI: \_SB_.GSIE: Enabled at IRQ 20
[    6.413790][    T1] pcieport 0000:00:04.0: PME: Signaling with IRQ 25
[    6.421868][    T1] pcieport 0000:00:04.0: AER: enabled with IRQ 26
[    6.437647][    T1] input: Power Button as /devices/platform/LNXPWRBN:00/input/input0
[    6.445066][    T1] ACPI: button: Power Button [PWRF]
[    6.840917][    T1] ioatdma: Intel(R) QuickData Technology Driver 5.00
[    6.842379][  T235] kworker/u33:7 (235) used greatest stack depth: 26728 bytes left
[    6.874382][    T1] ACPI: \_SB_.GSIF: Enabled at IRQ 21
[    6.924408][    T1] ACPI: \_SB_.GSIH: Enabled at IRQ 23
[    7.089820][  T387] kworker/u33:5 (387) used greatest stack depth: 26688 bytes left
[    7.223811][  T534] kworker/u33:5 (534) used greatest stack depth: 25576 bytes left
[    7.428304][    T1] N_HDLC line discipline registered with maxframe=4096
[    7.437551][    T1] Serial: 8250/16550 driver, 4 ports, IRQ sharing enabled
[    7.448472][    T1] 00:04: ttyS0 at I/O 0x3f8 (irq = 4, base_baud = 115200) is a 16550A
[    7.496195][    T1] Non-volatile memory driver v1.3
[    7.514250][    T1] usbcore: registered new interface driver xillyusb
[    7.527635][    T1] ACPI: bus type drm_connector registered
[    7.539604][    T1] [drm] Initialized vgem 1.0.0 for vgem on minor 0
[    7.544386][    T1] usbcore: registered new interface driver udl
[    7.549606][    T1] [drm] pci: virtio-vga detected at 0000:00:01.0
[    7.553602][    T1] virtio-pci 0000:00:01.0: vgaarb: deactivate vga console
[    7.582344][    T1] Console: switching to colour dummy device 80x25
[    7.591585][    T1] [drm] features: -virgl +edid -resource_blob -host_visible
[    7.591604][    T1] [drm] features: -context_init -blob_alignment
[    7.606984][    T1] [drm] number of scanouts: 1
[    7.609434][    T1] [drm] number of cap sets: 0
[    7.615497][    T1] ------------[ cut here ]------------
[    7.618695][    T1] [PLANE:36:plane-1] pixel format with alpha exposed but blend mode not setup
[    7.618711][    T1] WARNING: drivers/gpu/drm/drm_mode_config.c:872 at drm_mode_config_validate+0xfb4/0x1be0, CPU#3: swapper/0/1
[    7.631767][    T1] Modules linked in:
[    7.634235][    T1] CPU: 3 UID: 0 PID: 1 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
[    7.639231][    T1] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[    7.644605][    T1] RIP: 0010:drm_mode_config_validate+0xfbb/0x1be0
[    7.648817][    T1] Code: 00 49 8b 57 18 48 89 f8 48 c1 e8 03 0f b6 04 28 84 c0 74 08 3c 03 0f 8e 00 0b 00 00 48 8d 3d 3c 18 81 0b 41 8b b7 c8 00 00 00 <67> 48 0f b9 3a e9 fa fd ff ff 48 8b 5c 24 20 e8 41 aa 3c fc 48 8d
[    7.660004][    T1] RSP: 0000:ffffc90000047908 EFLAGS: 00010246
[    7.663325][    T1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[    7.667419][    T1] RDX: ffff8880283767c0 RSI: 0000000000000024 RDI: ffffffff914f8190
[    7.672329][    T1] RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000
[    7.677054][    T1] R10: 0000000000000001 R11: 0000000000000000 R12: ffffed1005094423
[    7.681820][    T1] R13: ffffed1005094424 R14: 0000000000000001 R15: ffff8880284a2028
[    7.686388][    T1] FS:  0000000000000000(0000) GS:ffff8880d5e88000(0000) knlGS:0000000000000000
[    7.691716][    T1] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    7.695512][    T1] CR2: 0000000000000000 CR3: 000000000eb94000 CR4: 0000000000352ef0
[    7.700076][    T1] Call Trace:
[    7.702162][    T1]  <TASK>
[    7.704132][    T1]  ? queue_work_on+0x137/0x1e0
[    7.707046][    T1]  drm_dev_register+0x56e/0x7b0
[    7.709670][    T1]  ? aperture_remove_conflicting_pci_devices+0x138/0x1e0
[    7.713695][    T1]  virtio_gpu_probe+0x271/0x360
[    7.716494][    T1]  virtio_dev_probe+0x6a2/0xbe0
[    7.719075][    T1]  ? __pfx_virtio_dev_probe+0x10/0x10
[    7.721871][    T1]  ? kernfs_create_link+0x1bd/0x240
[    7.724888][    T1]  ? kernfs_put+0x3f/0x60
[    7.727455][    T1]  ? sysfs_do_create_link_sd+0xbb/0x140
[    7.730461][    T1]  ? sysfs_create_link+0x68/0xc0
[    7.733024][    T1]  ? __pfx_virtio_dev_probe+0x10/0x10
[    7.736642][    T1]  really_probe+0x241/0xa60
[    7.739518][    T1]  __driver_probe_device+0x210/0x460
[    7.743005][    T1]  ? _raw_spin_unlock_irqrestore+0x52/0x80
[    7.746855][    T1]  driver_probe_device+0x4a/0x140
[    7.750272][    T1]  __driver_attach+0x21f/0x5b0
[    7.753271][    T1]  ? __pfx___driver_attach+0x10/0x10
[    7.756432][    T1]  bus_for_each_dev+0x13e/0x1d0
[    7.759384][    T1]  ? __pfx_bus_for_each_dev+0x10/0x10
[    7.763028][    T1]  ? bus_add_driver+0x2b5/0x5b0
[    7.765807][    T1]  bus_add_driver+0x305/0x5b0
[    7.768636][    T1]  driver_register+0x1e2/0x360
[    7.771737][    T1]  ? __pfx_virtio_gpu_driver_init+0x10/0x10
[    7.775777][    T1]  virtio_gpu_driver_init+0xc9/0x170
[    7.779251][    T1]  do_one_initcall+0x11c/0x6f0
[    7.781839][    T1]  ? __pfx_do_one_initcall+0x10/0x10
[    7.785228][    T1]  ? kasan_unpoison+0x22/0x60
[    7.788554][    T1]  ? kernel_init_freeable+0x4ca/0x7b0
[    7.792220][    T1]  kernel_init_freeable+0x6ea/0x7b0
[    7.795726][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.799065][    T1]  kernel_init+0x21/0x1e0
[    7.802141][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.805542][    T1]  ret_from_fork+0x730/0xd60
[    7.808865][    T1]  ? __pfx_ret_from_fork+0x10/0x10
[    7.812255][    T1]  ? __switch_to+0x800/0x10f0
[    7.815334][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.818677][    T1]  ret_from_fork_asm+0x1a/0x30
[    7.821765][    T1]  </TASK>
[    7.823834][    T1] Kernel panic - not syncing: kernel: panic_on_warn set ...
[    7.828642][    T1] CPU: 3 UID: 0 PID: 1 Comm: swapper/0 Not tainted syzkaller #0 PREEMPT(full) 
[    7.828642][    T1] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
[    7.828642][    T1] Call Trace:
[    7.828642][    T1]  <TASK>
[    7.828642][    T1]  dump_stack_lvl+0x100/0x190
[    7.828642][    T1]  vpanic+0x553/0x970
[    7.828642][    T1]  ? __pfx_vpanic+0x10/0x10
[    7.828642][    T1]  panic+0xd1/0xe0
[    7.828642][    T1]  ? __pfx_panic+0x10/0x10
[    7.828642][    T1]  check_panic_on_warn.cold+0x19/0x34
[    7.828642][    T1]  ? drm_mode_config_validate+0xfb4/0x1be0
[    7.828642][    T1]  __warn.cold+0x191/0x318
[    7.828642][    T1]  __report_bug+0x30f/0x440
[    7.828642][    T1]  ? drm_mode_config_validate+0xfb4/0x1be0
[    7.828642][    T1]  ? __pfx___report_bug+0x10/0x10
[    7.828642][    T1]  ? __pfx___might_resched+0x10/0x10
[    7.828642][    T1]  ? schedule_timeout+0x161/0x280
[    7.828642][    T1]  report_bug_entry+0xe2/0x290
[    7.828642][    T1]  ? drm_mode_config_validate+0xfbb/0x1be0
[    7.828642][    T1]  handle_bug+0x1cd/0x2a0
[    7.828642][    T1]  exc_invalid_op+0x17/0x50
[    7.828642][    T1]  asm_exc_invalid_op+0x1a/0x20
[    7.828642][    T1] RIP: 0010:drm_mode_config_validate+0xfbb/0x1be0
[    7.828642][    T1] Code: 00 49 8b 57 18 48 89 f8 48 c1 e8 03 0f b6 04 28 84 c0 74 08 3c 03 0f 8e 00 0b 00 00 48 8d 3d 3c 18 81 0b 41 8b b7 c8 00 00 00 <67> 48 0f b9 3a e9 fa fd ff ff 48 8b 5c 24 20 e8 41 aa 3c fc 48 8d
[    7.828642][    T1] RSP: 0000:ffffc90000047908 EFLAGS: 00010246
[    7.828642][    T1] RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
[    7.828642][    T1] RDX: ffff8880283767c0 RSI: 0000000000000024 RDI: ffffffff914f8190
[    7.828642][    T1] RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000
[    7.828642][    T1] R10: 0000000000000001 R11: 0000000000000000 R12: ffffed1005094423
[    7.828642][    T1] R13: ffffed1005094424 R14: 0000000000000001 R15: ffff8880284a2028
[    7.828642][    T1]  ? drm_mode_config_validate+0xf76/0x1be0
[    7.828642][    T1]  ? queue_work_on+0x137/0x1e0
[    7.828642][    T1]  drm_dev_register+0x56e/0x7b0
[    7.828642][    T1]  ? aperture_remove_conflicting_pci_devices+0x138/0x1e0
[    7.828642][    T1]  virtio_gpu_probe+0x271/0x360
[    7.828642][    T1]  virtio_dev_probe+0x6a2/0xbe0
[    7.828642][    T1]  ? __pfx_virtio_dev_probe+0x10/0x10
[    7.828642][    T1]  ? kernfs_create_link+0x1bd/0x240
[    7.828642][    T1]  ? kernfs_put+0x3f/0x60
[    7.828642][    T1]  ? sysfs_do_create_link_sd+0xbb/0x140
[    7.828642][    T1]  ? sysfs_create_link+0x68/0xc0
[    7.828642][    T1]  ? __pfx_virtio_dev_probe+0x10/0x10
[    7.828642][    T1]  really_probe+0x241/0xa60
[    7.828642][    T1]  __driver_probe_device+0x210/0x460
[    7.828642][    T1]  ? _raw_spin_unlock_irqrestore+0x52/0x80
[    7.828642][    T1]  driver_probe_device+0x4a/0x140
[    7.828642][    T1]  __driver_attach+0x21f/0x5b0
[    7.828642][    T1]  ? __pfx___driver_attach+0x10/0x10
[    7.828642][    T1]  bus_for_each_dev+0x13e/0x1d0
[    7.828642][    T1]  ? __pfx_bus_for_each_dev+0x10/0x10
[    7.828642][    T1]  ? bus_add_driver+0x2b5/0x5b0
[    7.828642][    T1]  bus_add_driver+0x305/0x5b0
[    7.828642][    T1]  driver_register+0x1e2/0x360
[    7.828642][    T1]  ? __pfx_virtio_gpu_driver_init+0x10/0x10
[    7.828642][    T1]  virtio_gpu_driver_init+0xc9/0x170
[    7.828642][    T1]  do_one_initcall+0x11c/0x6f0
[    7.828642][    T1]  ? __pfx_do_one_initcall+0x10/0x10
[    7.828642][    T1]  ? kasan_unpoison+0x22/0x60
[    7.828642][    T1]  ? kernel_init_freeable+0x4ca/0x7b0
[    7.828642][    T1]  kernel_init_freeable+0x6ea/0x7b0
[    7.828642][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.828642][    T1]  kernel_init+0x21/0x1e0
[    7.828642][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.828642][    T1]  ret_from_fork+0x730/0xd60
[    7.828642][    T1]  ? __pfx_ret_from_fork+0x10/0x10
[    7.828642][    T1]  ? __switch_to+0x800/0x10f0
[    7.828642][    T1]  ? __pfx_kernel_init+0x10/0x10
[    7.828642][    T1]  ret_from_fork_asm+0x1a/0x30
[    7.828642][    T1]  </TASK>
[    7.828642][    T1] Kernel Offset: disabled
[    7.828642][    T1] Rebooting in 86400 seconds..


syzkaller build log:
go env (err=<nil>)
AR='ar'
CC='gcc'
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_ENABLED='1'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
CXX='g++'
GCCGO='gccgo'
GO111MODULE='auto'
GOAMD64='v1'
GOARCH='amd64'
GOAUTH='netrc'
GOBIN=''
GOCACHE='/syzkaller/.cache/go-build'
GOCACHEPROG=''
GODEBUG=''
GOENV='/syzkaller/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFIPS140='off'
GOFLAGS=''
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build3835240120=/tmp/go-build -gno-record-gcc-switches'
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMOD='/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/go.mod'
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'
GOTELEMETRY='local'
GOTELEMETRYDIR='/syzkaller/.config/go/telemetry'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.26.0'
GOWORK=''
PKG_CONFIG='pkg-config'

git status (err=<nil>)
HEAD detached at a9ede23c6b9
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}}' -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=a9ede23c6b9721e9bd95dcb2343c1d6c68e4f0ac -X github.com/google/syzkaller/prog.gitRevisionDate=20260813-125026"  ./sys/syz-sysgen | grep -q false || go install -ldflags="-s -w -X github.com/google/syzkaller/prog.GitRevision=a9ede23c6b9721e9bd95dcb2343c1d6c68e4f0ac -X github.com/google/syzkaller/prog.gitRevisionDate=20260813-125026"  ./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=a9ede23c6b9721e9bd95dcb2343c1d6c68e4f0ac -X github.com/google/syzkaller/prog.gitRevisionDate=20260813-125026"  -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog
mkdir -p ./bin/linux_amd64
g++ -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 -std=c++17 -I. -Iexecutor/_include   -DGOOS_linux=1 -DGOARCH_amd64=1 \
	-DHOSTGOOS_linux=1 -DGIT_REVISION=\"a9ede23c6b9721e9bd95dcb2343c1d6c68e4f0ac\"
/usr/bin/ld: /tmp/ccGWcbwL.o: in function `Connection::Connect(char const*, char const*)':
executor.cc:(.text._ZN10Connection7ConnectEPKcS1_[_ZN10Connection7ConnectEPKcS1_]+0x386): warning: Using 'gethostbyname' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking
./tools/check-syzos.sh 2>/dev/null


Error text is too large and was truncated, full error text is at:
https://syzkaller.appspot.com/x/error.txt?x=1548be79580000


Tested on:

commit:         26260251 Merge tag 'livepatching-for-7.3' of git://git..
git tree:       upstream
kernel config:  https://syzkaller.appspot.com/x/.config?x=b0978f5ed2905b98
dashboard link: https://syzkaller.appspot.com/bug?extid=ecbb1750082f7528b507
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44
patch:          https://syzkaller.appspot.com/x/patch.diff?x=16bc0625580000


      reply	other threads:[~2026-08-22  0:54 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-20 14:58 [syzbot] KASAN: slab-use-after-free Read in vhci_send_cmd_submit syzbot
2026-08-21  3:13 ` Edward Adam Davis
2026-08-21  3:29   ` syzbot
2026-08-21  4:55 ` Hillf Danton
2026-08-21  5:11   ` syzbot
2026-08-21 13:08 ` [PATCH] usbip: prevent the use of unavailable urb and hcpriv in tx Edward Adam Davis
2026-08-22  0:30 ` [syzbot] KASAN: slab-use-after-free Read in vhci_send_cmd_submit Hillf Danton
2026-08-22  0:54   ` syzbot [this message]

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