Extracting prog: 3m50.923256949s
Minimizing prog: 4m24.628734444s
Simplifying prog options: 0s
Extracting C: 1m18.704369104s
Simplifying C: 18m56.71631898s


extracting reproducer from 1 programs
testing a last program of every proc
single: executing 1 programs separately with timeout 30s
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
detailed listing:
executing program 0:
syz_usb_connect(0x0, 0x2d, &(0x7f00000009c0)=ANY=[@ANYBLOB="9f01000083667d1040206502d14e0102030109021b0001f6000000090400000190f19c000905f3ed8295091f8fee2efe39472f1ea3227d052d7556c97a470fa22bee95e09780953cc585369ad5511fb3243191c3"], 0x0)

program did not crash
single: failed to extract reproducer
single: executing 1 programs separately with timeout 1m40s
testing program (duration=1m40s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
detailed listing:
executing program 0:
syz_usb_connect(0x0, 0x2d, &(0x7f00000009c0)=ANY=[@ANYBLOB="9f01000083667d1040206502d14e0102030109021b0001f6000000090400000190f19c000905f3ed8295091f8fee2efe39472f1ea3227d052d7556c97a470fa22bee95e09780953cc585369ad5511fb3243191c3"], 0x0)

program crashed: KASAN: use-after-free Read in em28xx_close_extension
single: successfully extracted reproducer
found reproducer with 1 syscalls
minimizing guilty program
testing program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
detailed listing:
executing program 0:
syz_usb_connect(0x0, 0x2d, 0x0, 0x0)

program did not crash
testing program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
detailed listing:
executing program 0:
syz_usb_connect(0x0, 0x2d, &(0x7f00000009c0)=ANY=[@ANYBLOB], 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: use-after-free Read in em28xx_close_extension
simplifying C reproducer
testing compiled C program (duration=2m4.980373884s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: slab-out-of-bounds Read in em28xx_close_extension
a never seen crash title: KASAN: slab-out-of-bounds Read in em28xx_close_extension, ignore
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: BUG: corrupted list in em28xx_init_extension
a never seen crash title: BUG: corrupted list in em28xx_init_extension, ignore
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: BUG: corrupted list in em28xx_close_extension
a never seen crash title: BUG: corrupted list in em28xx_close_extension, ignore
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: slab-out-of-bounds Read in em28xx_close_extension
a never seen crash title: KASAN: slab-out-of-bounds Read in em28xx_close_extension, ignore
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: use-after-free Read in em28xx_close_extension
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: use-after-free Read in em28xx_close_extension
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: BUG: corrupted list in em28xx_close_extension
a never seen crash title: BUG: corrupted list in em28xx_close_extension, ignore
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: BUG: corrupted list in em28xx_close_extension
a never seen crash title: BUG: corrupted list in em28xx_close_extension, ignore
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: BUG: corrupted list in em28xx_init_extension
a never seen crash title: BUG: corrupted list in em28xx_init_extension, ignore
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: slab-out-of-bounds Read in em28xx_close_extension
a never seen crash title: KASAN: slab-out-of-bounds Read in em28xx_close_extension, ignore
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: use-after-free Read in em28xx_close_extension
testing compiled C program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: BUG: corrupted list in em28xx_close_extension
a never seen crash title: BUG: corrupted list in em28xx_close_extension, ignore
testing program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
detailed listing:
executing program 0:
syz_usb_connect(0x0, 0x2d, &(0x7f00000009c0)=ANY=[@ANYBLOB="9f01000083667d1040206502d14e0102030109021b0001f6000000090400000190f19c000905f3ed8295091f8fee2efe39472f1ea3227d052d7556c97a470fa22bee95e09780953cc585369ad5511fb3243191c3"], 0x0)

program crashed: KASAN: use-after-free Read in em28xx_close_extension
validation run: crashed=true
testing program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
detailed listing:
executing program 0:
syz_usb_connect(0x0, 0x2d, &(0x7f00000009c0)=ANY=[@ANYBLOB="9f01000083667d1040206502d14e0102030109021b0001f6000000090400000190f19c000905f3ed8295091f8fee2efe39472f1ea3227d052d7556c97a470fa22bee95e09780953cc585369ad5511fb3243191c3"], 0x0)

program crashed: BUG: corrupted list in em28xx_close_extension
validation run: crashed=true
testing program (duration=2m4.980373884s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
detailed listing:
executing program 0:
syz_usb_connect(0x0, 0x2d, &(0x7f00000009c0)=ANY=[@ANYBLOB="9f01000083667d1040206502d14e0102030109021b0001f6000000090400000190f19c000905f3ed8295091f8fee2efe39472f1ea3227d052d7556c97a470fa22bee95e09780953cc585369ad5511fb3243191c3"], 0x0)

program crashed: KASAN: slab-use-after-free Read in em28xx_close_extension
validation run: crashed=true
reproducing took 34m16.810005018s
repro crashed as (corrupted=false):
usb 8-1: USB disconnect, device number 2
em28xx 8-1:246.0: Disconnecting em28xx #7
em28xx 8-1:246.0: Disconnecting em28xx
==================================================================
BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x1b1/0x1d0 lib/list_debug.c:62
Read of size 8 at addr ffff88811fe0c250 by task kworker/1:3/2812

CPU: 1 UID: 0 PID: 2812 Comm: kworker/1:3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x156/0x4c9 mm/kasan/report.c:482
 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595
 __list_del_entry_valid_or_report+0x1b1/0x1d0 lib/list_debug.c:62
 __list_del_entry_valid include/linux/list.h:132 [inline]
 __list_del_entry include/linux/list.h:223 [inline]
 list_del include/linux/list.h:237 [inline]
 em28xx_close_extension+0x10b/0x2b0 drivers/media/usb/em28xx/em28xx-core.c:1137
 em28xx_usb_disconnect.cold+0x13d/0x253 drivers/media/usb/em28xx/em28xx-cards.c:4197
 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:573 [inline]
 device_remove+0x12a/0x180 drivers/base/dd.c:565
 __device_release_driver drivers/base/dd.c:1284 [inline]
 device_release_driver_internal+0x42e/0x600 drivers/base/dd.c:1307
 bus_remove_device+0x22f/0x440 drivers/base/bus.c:616
 device_del+0x376/0x9b0 drivers/base/core.c:3878
 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
 usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2345
 hub_port_connect drivers/usb/core/hub.c:5407 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 port_event drivers/usb/core/hub.c:5871 [inline]
 hub_event+0x1d0c/0x4af0 drivers/usb/core/hub.c:5953
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 5776:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6e/0x70 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4538 [inline]
 slab_alloc_node mm/slub.c:4866 [inline]
 kmem_cache_alloc_node_noprof+0x26b/0x6b0 mm/slub.c:4918
 kmalloc_reserve+0x148/0x350 net/core/skbuff.c:613
 __alloc_skb+0x185/0x710 net/core/skbuff.c:713
 alloc_skb include/linux/skbuff.h:1383 [inline]
 netlink_alloc_large_skb+0x69/0x150 net/netlink/af_netlink.c:1184
 netlink_sendmsg+0x680/0xda0 net/netlink/af_netlink.c:1869
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0x9e1/0xb70 net/socket.c:2592
 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
 __sys_sendmsg+0x170/0x220 net/socket.c:2678
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0x7b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5776:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x43/0x70 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2685 [inline]
 slab_free mm/slub.c:6165 [inline]
 kmem_cache_free+0x105/0x640 mm/slub.c:6295
 skb_kfree_head net/core/skbuff.c:1087 [inline]
 skb_kfree_head net/core/skbuff.c:1084 [inline]
 skb_free_head+0x1c6/0x220 net/core/skbuff.c:1101
 skb_release_data+0x79b/0x9d0 net/core/skbuff.c:1128
 skb_release_all net/core/skbuff.c:1203 [inline]
 __kfree_skb net/core/skbuff.c:1217 [inline]
 consume_skb net/core/skbuff.c:1450 [inline]
 consume_skb+0xc4/0x110 net/core/skbuff.c:1444
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x5b2/0x870 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0x9e1/0xb70 net/socket.c:2592
 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
 __sys_sendmsg+0x170/0x220 net/socket.c:2678
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0x7b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88811fe0c000
 which belongs to the cache skbuff_small_head of size 704
The buggy address is located 592 bytes inside of
 freed 704-byte region [ffff88811fe0c000, ffff88811fe0c2c0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11fe0c
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff888102affb40 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800130013 00000000f5000000 0000000000000000
head: 0200000000000040 ffff888102affb40 dead000000000100 dead000000000122
head: 0000000000000000 0000000800130013 00000000f5000000 0000000000000000
head: 0200000000000002 ffffea00047f8301 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 22, tgid 22 (ksoftirqd/1), ts 129087357629, free_ts 128964937459
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0xf10/0x39f0 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x273/0x2860 mm/page_alloc.c:5250
 alloc_slab_page mm/slub.c:3292 [inline]
 allocate_slab mm/slub.c:3481 [inline]
 new_slab+0xa6/0x6c0 mm/slub.c:3539
 refill_objects+0x26b/0x400 mm/slub.c:7175
 refill_sheaf mm/slub.c:2812 [inline]
 __pcs_replace_empty_main+0x1ab/0x660 mm/slub.c:4615
 alloc_from_pcs mm/slub.c:4717 [inline]
 slab_alloc_node mm/slub.c:4851 [inline]
 kmem_cache_alloc_node_noprof+0x4e9/0x6b0 mm/slub.c:4918
 kmalloc_reserve+0x148/0x350 net/core/skbuff.c:613
 __alloc_skb+0x185/0x710 net/core/skbuff.c:713
 alloc_skb include/linux/skbuff.h:1383 [inline]
 __tcp_send_ack.part.0+0x66/0x730 net/ipv4/tcp_output.c:4476
 __tcp_send_ack net/ipv4/tcp_output.c:4509 [inline]
 tcp_send_ack+0x84/0xa0 net/ipv4/tcp_output.c:4509
 __tcp_ack_snd_check+0x1fe/0x9f0 net/ipv4/tcp_input.c:6163
 tcp_ack_snd_check net/ipv4/tcp_input.c:6217 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:6211 [inline]
 tcp_rcv_established+0xcf2/0x3970 net/ipv4/tcp_input.c:6711
 tcp_v4_do_rcv+0x5e4/0xad0 net/ipv4/tcp_ipv4.c:1884
 tcp_v4_rcv+0x2d34/0x3fd0 net/ipv4/tcp_ipv4.c:2319
 ip_protocol_deliver_rcu+0xba/0x4d0 net/ipv4/ip_input.c:207
page last free pid 28 tgid 28 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1433 [inline]
 __free_frozen_pages+0x7b1/0xfb0 mm/page_alloc.c:2978
 kref_put.constprop.0.isra.0+0x4d/0x6d include/linux/kref.h:65
 em28xx_usb_disconnect.cold+0x1b4/0x253 drivers/media/usb/em28xx/em28xx-cards.c:4204
 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:573 [inline]
 device_remove+0x12a/0x180 drivers/base/dd.c:565
 __device_release_driver drivers/base/dd.c:1284 [inline]
 device_release_driver_internal+0x42e/0x600 drivers/base/dd.c:1307
 bus_remove_device+0x22f/0x440 drivers/base/bus.c:616
 device_del+0x376/0x9b0 drivers/base/core.c:3878
 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
 usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2345
 hub_port_connect drivers/usb/core/hub.c:5407 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 port_event drivers/usb/core/hub.c:5871 [inline]
 hub_event+0x1d0c/0x4af0 drivers/usb/core/hub.c:5953
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88811fe0c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811fe0c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88811fe0c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88811fe0c280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88811fe0c300: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
==================================================================

final repro crashed as (corrupted=false):
usb 8-1: USB disconnect, device number 2
em28xx 8-1:246.0: Disconnecting em28xx #7
em28xx 8-1:246.0: Disconnecting em28xx
==================================================================
BUG: KASAN: slab-use-after-free in __list_del_entry_valid_or_report+0x1b1/0x1d0 lib/list_debug.c:62
Read of size 8 at addr ffff88811fe0c250 by task kworker/1:3/2812

CPU: 1 UID: 0 PID: 2812 Comm: kworker/1:3 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x156/0x4c9 mm/kasan/report.c:482
 kasan_report+0xdf/0x1e0 mm/kasan/report.c:595
 __list_del_entry_valid_or_report+0x1b1/0x1d0 lib/list_debug.c:62
 __list_del_entry_valid include/linux/list.h:132 [inline]
 __list_del_entry include/linux/list.h:223 [inline]
 list_del include/linux/list.h:237 [inline]
 em28xx_close_extension+0x10b/0x2b0 drivers/media/usb/em28xx/em28xx-core.c:1137
 em28xx_usb_disconnect.cold+0x13d/0x253 drivers/media/usb/em28xx/em28xx-cards.c:4197
 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:573 [inline]
 device_remove+0x12a/0x180 drivers/base/dd.c:565
 __device_release_driver drivers/base/dd.c:1284 [inline]
 device_release_driver_internal+0x42e/0x600 drivers/base/dd.c:1307
 bus_remove_device+0x22f/0x440 drivers/base/bus.c:616
 device_del+0x376/0x9b0 drivers/base/core.c:3878
 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
 usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2345
 hub_port_connect drivers/usb/core/hub.c:5407 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 port_event drivers/usb/core/hub.c:5871 [inline]
 hub_event+0x1d0c/0x4af0 drivers/usb/core/hub.c:5953
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 5776:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 unpoison_slab_object mm/kasan/common.c:340 [inline]
 __kasan_slab_alloc+0x6e/0x70 mm/kasan/common.c:366
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4538 [inline]
 slab_alloc_node mm/slub.c:4866 [inline]
 kmem_cache_alloc_node_noprof+0x26b/0x6b0 mm/slub.c:4918
 kmalloc_reserve+0x148/0x350 net/core/skbuff.c:613
 __alloc_skb+0x185/0x710 net/core/skbuff.c:713
 alloc_skb include/linux/skbuff.h:1383 [inline]
 netlink_alloc_large_skb+0x69/0x150 net/netlink/af_netlink.c:1184
 netlink_sendmsg+0x680/0xda0 net/netlink/af_netlink.c:1869
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0x9e1/0xb70 net/socket.c:2592
 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
 __sys_sendmsg+0x170/0x220 net/socket.c:2678
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0x7b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5776:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x43/0x70 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2685 [inline]
 slab_free mm/slub.c:6165 [inline]
 kmem_cache_free+0x105/0x640 mm/slub.c:6295
 skb_kfree_head net/core/skbuff.c:1087 [inline]
 skb_kfree_head net/core/skbuff.c:1084 [inline]
 skb_free_head+0x1c6/0x220 net/core/skbuff.c:1101
 skb_release_data+0x79b/0x9d0 net/core/skbuff.c:1128
 skb_release_all net/core/skbuff.c:1203 [inline]
 __kfree_skb net/core/skbuff.c:1217 [inline]
 consume_skb net/core/skbuff.c:1450 [inline]
 consume_skb+0xc4/0x110 net/core/skbuff.c:1444
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x5b2/0x870 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8b0/0xda0 net/netlink/af_netlink.c:1894
 sock_sendmsg_nosec net/socket.c:727 [inline]
 __sock_sendmsg net/socket.c:742 [inline]
 ____sys_sendmsg+0x9e1/0xb70 net/socket.c:2592
 ___sys_sendmsg+0x190/0x1e0 net/socket.c:2646
 __sys_sendmsg+0x170/0x220 net/socket.c:2678
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x106/0x7b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff88811fe0c000
 which belongs to the cache skbuff_small_head of size 704
The buggy address is located 592 bytes inside of
 freed 704-byte region [ffff88811fe0c000, ffff88811fe0c2c0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11fe0c
head: order:2 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff888102affb40 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800130013 00000000f5000000 0000000000000000
head: 0200000000000040 ffff888102affb40 dead000000000100 dead000000000122
head: 0000000000000000 0000000800130013 00000000f5000000 0000000000000000
head: 0200000000000002 ffffea00047f8301 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000004
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 22, tgid 22 (ksoftirqd/1), ts 129087357629, free_ts 128964937459
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x153/0x170 mm/page_alloc.c:1889
 prep_new_page mm/page_alloc.c:1897 [inline]
 get_page_from_freelist+0xf10/0x39f0 mm/page_alloc.c:3962
 __alloc_frozen_pages_noprof+0x273/0x2860 mm/page_alloc.c:5250
 alloc_slab_page mm/slub.c:3292 [inline]
 allocate_slab mm/slub.c:3481 [inline]
 new_slab+0xa6/0x6c0 mm/slub.c:3539
 refill_objects+0x26b/0x400 mm/slub.c:7175
 refill_sheaf mm/slub.c:2812 [inline]
 __pcs_replace_empty_main+0x1ab/0x660 mm/slub.c:4615
 alloc_from_pcs mm/slub.c:4717 [inline]
 slab_alloc_node mm/slub.c:4851 [inline]
 kmem_cache_alloc_node_noprof+0x4e9/0x6b0 mm/slub.c:4918
 kmalloc_reserve+0x148/0x350 net/core/skbuff.c:613
 __alloc_skb+0x185/0x710 net/core/skbuff.c:713
 alloc_skb include/linux/skbuff.h:1383 [inline]
 __tcp_send_ack.part.0+0x66/0x730 net/ipv4/tcp_output.c:4476
 __tcp_send_ack net/ipv4/tcp_output.c:4509 [inline]
 tcp_send_ack+0x84/0xa0 net/ipv4/tcp_output.c:4509
 __tcp_ack_snd_check+0x1fe/0x9f0 net/ipv4/tcp_input.c:6163
 tcp_ack_snd_check net/ipv4/tcp_input.c:6217 [inline]
 tcp_ack_snd_check net/ipv4/tcp_input.c:6211 [inline]
 tcp_rcv_established+0xcf2/0x3970 net/ipv4/tcp_input.c:6711
 tcp_v4_do_rcv+0x5e4/0xad0 net/ipv4/tcp_ipv4.c:1884
 tcp_v4_rcv+0x2d34/0x3fd0 net/ipv4/tcp_ipv4.c:2319
 ip_protocol_deliver_rcu+0xba/0x4d0 net/ipv4/ip_input.c:207
page last free pid 28 tgid 28 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1433 [inline]
 __free_frozen_pages+0x7b1/0xfb0 mm/page_alloc.c:2978
 kref_put.constprop.0.isra.0+0x4d/0x6d include/linux/kref.h:65
 em28xx_usb_disconnect.cold+0x1b4/0x253 drivers/media/usb/em28xx/em28xx-cards.c:4204
 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:573 [inline]
 device_remove+0x12a/0x180 drivers/base/dd.c:565
 __device_release_driver drivers/base/dd.c:1284 [inline]
 device_release_driver_internal+0x42e/0x600 drivers/base/dd.c:1307
 bus_remove_device+0x22f/0x440 drivers/base/bus.c:616
 device_del+0x376/0x9b0 drivers/base/core.c:3878
 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
 usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2345
 hub_port_connect drivers/usb/core/hub.c:5407 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5707 [inline]
 port_event drivers/usb/core/hub.c:5871 [inline]
 hub_event+0x1d0c/0x4af0 drivers/usb/core/hub.c:5953
 process_one_work+0xa23/0x19a0 kernel/workqueue.c:3276
 process_scheduled_works kernel/workqueue.c:3359 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3440
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff88811fe0c100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811fe0c180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88811fe0c200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                 ^
 ffff88811fe0c280: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff88811fe0c300: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
==================================================================