Extracting prog: 5m10.148735862s
Minimizing prog: 24m49.299257477s
Simplifying prog options: 0s
Extracting C: 24.427452127s
Simplifying C: 30m39.181954162s


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:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io-syz_usb_connect-ioctl$EVIOCGMASK
detailed listing:
executing program 0:
syz_usb_connect(0x3, 0x2d, &(0x7f0000000000)={{0x12, 0x1, 0x0, 0xcf, 0xc5, 0x30, 0x10, 0xeb1a, 0xe303, 0x2ab3, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x0, 0x0, [{{0x9, 0x4, 0xed, 0x2, 0x1, 0x14, 0x30, 0x90, 0x0, [], [{{0x9, 0x5, 0x82, 0x3, 0x40}}]}}]}}]}}, 0x0)
syz_usb_control_io(0xffffffffffffffff, 0x0, 0x0)
syz_usb_connect(0x0, 0x24, 0x0, 0x0)
ioctl$EVIOCGMASK(0xffffffffffffffff, 0x80104592, 0x0)

program did not crash
single: failed to extract reproducer
single: executing 1 programs separately with timeout 6m0s
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io-syz_usb_connect-ioctl$EVIOCGMASK
detailed listing:
executing program 0:
syz_usb_connect(0x3, 0x2d, &(0x7f0000000000)={{0x12, 0x1, 0x0, 0xcf, 0xc5, 0x30, 0x10, 0xeb1a, 0xe303, 0x2ab3, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x0, 0x0, [{{0x9, 0x4, 0xed, 0x2, 0x1, 0x14, 0x30, 0x90, 0x0, [], [{{0x9, 0x5, 0x82, 0x3, 0x40}}]}}]}}]}}, 0x0)
syz_usb_control_io(0xffffffffffffffff, 0x0, 0x0)
syz_usb_connect(0x0, 0x24, 0x0, 0x0)
ioctl$EVIOCGMASK(0xffffffffffffffff, 0x80104592, 0x0)

program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
single: successfully extracted reproducer
found reproducer with 4 syscalls
minimizing guilty program
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io-syz_usb_connect
detailed listing:
executing program 0:
syz_usb_connect(0x3, 0x2d, &(0x7f0000000000)={{0x12, 0x1, 0x0, 0xcf, 0xc5, 0x30, 0x10, 0xeb1a, 0xe303, 0x2ab3, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x0, 0x0, [{{0x9, 0x4, 0xed, 0x2, 0x1, 0x14, 0x30, 0x90, 0x0, [], [{{0x9, 0x5, 0x82, 0x3, 0x40}}]}}]}}]}}, 0x0)
syz_usb_control_io(0xffffffffffffffff, 0x0, 0x0)
syz_usb_connect(0x0, 0x24, 0x0, 0x0)

program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
detailed listing:
executing program 0:
syz_usb_connect(0x3, 0x2d, &(0x7f0000000000)={{0x12, 0x1, 0x0, 0xcf, 0xc5, 0x30, 0x10, 0xeb1a, 0xe303, 0x2ab3, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x0, 0x0, [{{0x9, 0x4, 0xed, 0x2, 0x1, 0x14, 0x30, 0x90, 0x0, [], [{{0x9, 0x5, 0x82, 0x3, 0x40}}]}}]}}]}}, 0x0)
syz_usb_control_io(0xffffffffffffffff, 0x0, 0x0)

program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true 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(0x3, 0x2d, &(0x7f0000000000)={{0x12, 0x1, 0x0, 0xcf, 0xc5, 0x30, 0x10, 0xeb1a, 0xe303, 0x2ab3, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x0, 0x0, [{{0x9, 0x4, 0xed, 0x2, 0x1, 0x14, 0x30, 0x90, 0x0, [], [{{0x9, 0x5, 0x82, 0x3, 0x40}}]}}]}}]}}, 0x0)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_control_io
detailed listing:
executing program 0:
syz_usb_control_io(0xffffffffffffffff, 0x0, 0x0)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
detailed listing:
executing program 0:
syz_usb_connect(0x3, 0x0, 0x0, 0x0)
syz_usb_control_io(0xffffffffffffffff, 0x0, 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
simplifying C reproducer
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:4 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:true Wifi:true IEEE802154:true Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:true Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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-syz_usb_control_io
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:true Sysctl:true Swap:false UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:true Sysctl:true Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
program crashed: no output from test machine
a never seen crash title: no output from test machine, ignore
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:true Sysctl:false Swap:false UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:true Sysctl:false Swap:false UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
detailed listing:
executing program 0:
syz_usb_connect(0x3, 0x2d, &(0x7f0000000000)={{0x12, 0x1, 0x0, 0xcf, 0xc5, 0x30, 0x10, 0xeb1a, 0xe303, 0x2ab3, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x0, 0x0, [{{0x9, 0x4, 0xed, 0x2, 0x1, 0x14, 0x30, 0x90, 0x0, [], [{{0x9, 0x5, 0x82, 0x3, 0x40}}]}}]}}]}}, 0x0)
syz_usb_control_io(0xffffffffffffffff, 0x0, 0x0)

program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
validation run: crashed=true
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:true Sysctl:false Swap:false UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
detailed listing:
executing program 0:
syz_usb_connect(0x3, 0x2d, &(0x7f0000000000)={{0x12, 0x1, 0x0, 0xcf, 0xc5, 0x30, 0x10, 0xeb1a, 0xe303, 0x2ab3, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x0, 0x0, [{{0x9, 0x4, 0xed, 0x2, 0x1, 0x14, 0x30, 0x90, 0x0, [], [{{0x9, 0x5, 0x82, 0x3, 0x40}}]}}]}}]}}, 0x0)
syz_usb_control_io(0xffffffffffffffff, 0x0, 0x0)

program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
validation run: crashed=true
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:4 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:true Sysctl:false Swap:false UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect-syz_usb_control_io
detailed listing:
executing program 0:
syz_usb_connect(0x3, 0x2d, &(0x7f0000000000)={{0x12, 0x1, 0x0, 0xcf, 0xc5, 0x30, 0x10, 0xeb1a, 0xe303, 0x2ab3, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x0, 0x0, [{{0x9, 0x4, 0xed, 0x2, 0x1, 0x14, 0x30, 0x90, 0x0, [], [{{0x9, 0x5, 0x82, 0x3, 0x40}}]}}]}}]}}, 0x0)
syz_usb_control_io(0xffffffffffffffff, 0x0, 0x0)

program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
validation run: crashed=true
reproducing took 1h6m1.803002653s
repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: slab-use-after-free in v4l2_fh_init+0x27d/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25
Read of size 8 at addr ffff888025788740 by task v4l_id/6765

CPU: 1 UID: 0 PID: 6765 Comm: v4l_id Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 v4l2_fh_init+0x27d/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25
 v4l2_fh_open+0x64/0xa0 drivers/media/v4l2-core/v4l2-fh.c:64
 em28xx_v4l2_open+0x24e/0x7e0 drivers/media/usb/em28xx/em28xx-video.c:2153
 v4l2_open+0x1d2/0x5e0 drivers/media/v4l2-core/v4l2-dev.c:433
 chrdev_open+0x234/0x6a0 fs/char_dev.c:414
 do_dentry_open+0x748/0x1590 fs/open.c:962
 vfs_open+0x82/0x3f0 fs/open.c:1094
 do_open fs/namei.c:4628 [inline]
 path_openat+0x2078/0x3140 fs/namei.c:4787
 do_filp_open+0x20b/0x470 fs/namei.c:4814
 do_sys_openat2+0x11f/0x280 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fde7bca7407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fff6d95bac0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fde7c4ad880 RCX: 00007fde7bca7407
RDX: 0000000000000000 RSI: 00007fff6d95bf1b RDI: ffffffffffffff9c
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fff6d95bd10 R14: 00007fde7c614000 R15: 0000557aac7714d8
 </TASK>

Allocated by task 9:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 em28xx_v4l2_init+0x114/0x4080 drivers/media/usb/em28xx/em28xx-video.c:2532
 em28xx_init_extension+0x13a/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117
 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3263
 process_scheduled_works kernel/workqueue.c:3346 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Freed by task 9:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587
 kasan_save_free_info mm/kasan/kasan.h:406 [inline]
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2543 [inline]
 slab_free mm/slub.c:6642 [inline]
 kfree+0x29e/0x710 mm/slub.c:6849
 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2118 [inline]
 kref_put include/linux/kref.h:65 [inline]
 em28xx_v4l2_init+0x22b5/0x4080 drivers/media/usb/em28xx/em28xx-video.c:2901
 em28xx_init_extension+0x13a/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117
 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3263
 process_scheduled_works kernel/workqueue.c:3346 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

The buggy address belongs to the object at ffff888025788000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 1856 bytes inside of
 freed 8192-byte region [ffff888025788000, ffff88802578a000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25788
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b443180 0000000000000000 dead000000000001
raw: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b443180 0000000000000000 dead000000000001
head: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea000095e201 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6019, tgid 6019 (syz-executor), ts 135767389421, free_ts 134921024956
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1845
 prep_new_page mm/page_alloc.c:1853 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3879
 __alloc_frozen_pages_noprof+0x25f/0x2440 mm/page_alloc.c:5178
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:3059 [inline]
 allocate_slab mm/slub.c:3232 [inline]
 new_slab+0x24a/0x360 mm/slub.c:3286
 ___slab_alloc+0xee7/0x1cd0 mm/slub.c:4655
 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4778
 __slab_alloc_node mm/slub.c:4854 [inline]
 slab_alloc_node mm/slub.c:5276 [inline]
 __do_kmalloc_node mm/slub.c:5649 [inline]
 __kmalloc_noprof+0x501/0x870 mm/slub.c:5662
 kmalloc_noprof include/linux/slab.h:961 [inline]
 kmalloc_array_noprof include/linux/slab.h:1003 [inline]
 cache_create_net+0x9d/0x220 net/sunrpc/cache.c:1747
 rsc_cache_create_net net/sunrpc/auth_gss/svcauth_gss.c:2053 [inline]
 gss_svc_init_net+0x69/0x660 net/sunrpc/auth_gss/svcauth_gss.c:2081
 ops_init+0x1e2/0x5f0 net/core/net_namespace.c:137
 setup_net+0x11d/0x3a0 net/core/net_namespace.c:445
 copy_net_ns+0x351/0x5d0 net/core/net_namespace.c:580
 create_new_namespaces+0x3ea/0xab0 kernel/nsproxy.c:130
 unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x45b/0xa40 kernel/fork.c:3129
page last free pid 6002 tgid 6002 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2901
 __folio_put+0x329/0x450 mm/swap.c:112
 folio_put include/linux/mm.h:1425 [inline]
 put_page+0x209/0x270 include/linux/mm.h:1494
 put_netmem net/core/skbuff.c:7376 [inline]
 skb_page_unref include/linux/skbuff_ref.h:43 [inline]
 __skb_frag_unref include/linux/skbuff_ref.h:56 [inline]
 skb_release_data+0x459/0x7a0 net/core/skbuff.c:1081
 skb_release_all net/core/skbuff.c:1152 [inline]
 __kfree_skb net/core/skbuff.c:1166 [inline]
 napi_consume_skb+0x1b7/0x220 net/core/skbuff.c:1476
 skb_defer_free_flush+0x1e2/0x280 net/core/dev.c:6735
 net_rx_action+0x3b3/0xfe0 net/core/dev.c:7765
 handle_softirqs+0x219/0x8b0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x57/0xc0 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697

Memory state around the buggy address:
 ffff888025788600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888025788680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888025788700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff888025788780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888025788800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

final repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: slab-use-after-free in v4l2_fh_init+0x27d/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25
Read of size 8 at addr ffff888025788740 by task v4l_id/6765

CPU: 1 UID: 0 PID: 6765 Comm: v4l_id Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 v4l2_fh_init+0x27d/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25
 v4l2_fh_open+0x64/0xa0 drivers/media/v4l2-core/v4l2-fh.c:64
 em28xx_v4l2_open+0x24e/0x7e0 drivers/media/usb/em28xx/em28xx-video.c:2153
 v4l2_open+0x1d2/0x5e0 drivers/media/v4l2-core/v4l2-dev.c:433
 chrdev_open+0x234/0x6a0 fs/char_dev.c:414
 do_dentry_open+0x748/0x1590 fs/open.c:962
 vfs_open+0x82/0x3f0 fs/open.c:1094
 do_open fs/namei.c:4628 [inline]
 path_openat+0x2078/0x3140 fs/namei.c:4787
 do_filp_open+0x20b/0x470 fs/namei.c:4814
 do_sys_openat2+0x11f/0x280 fs/open.c:1430
 do_sys_open fs/open.c:1436 [inline]
 __do_sys_openat fs/open.c:1452 [inline]
 __se_sys_openat fs/open.c:1447 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1447
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0xf80 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fde7bca7407
Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
RSP: 002b:00007fff6d95bac0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fde7c4ad880 RCX: 00007fde7bca7407
RDX: 0000000000000000 RSI: 00007fff6d95bf1b RDI: ffffffffffffff9c
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fff6d95bd10 R14: 00007fde7c614000 R15: 0000557aac7714d8
 </TASK>

Allocated by task 9:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:417
 kmalloc_noprof include/linux/slab.h:957 [inline]
 kzalloc_noprof include/linux/slab.h:1094 [inline]
 em28xx_v4l2_init+0x114/0x4080 drivers/media/usb/em28xx/em28xx-video.c:2532
 em28xx_init_extension+0x13a/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117
 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3263
 process_scheduled_works kernel/workqueue.c:3346 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

Freed by task 9:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:56
 kasan_save_track+0x14/0x30 mm/kasan/common.c:77
 __kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:587
 kasan_save_free_info mm/kasan/kasan.h:406 [inline]
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2543 [inline]
 slab_free mm/slub.c:6642 [inline]
 kfree+0x29e/0x710 mm/slub.c:6849
 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2118 [inline]
 kref_put include/linux/kref.h:65 [inline]
 em28xx_v4l2_init+0x22b5/0x4080 drivers/media/usb/em28xx/em28xx-video.c:2901
 em28xx_init_extension+0x13a/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117
 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457
 process_one_work+0x9ba/0x1b20 kernel/workqueue.c:3263
 process_scheduled_works kernel/workqueue.c:3346 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3427
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x983/0xb10 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

The buggy address belongs to the object at ffff888025788000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 1856 bytes inside of
 freed 8192-byte region [ffff888025788000, ffff88802578a000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x25788
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b443180 0000000000000000 dead000000000001
raw: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b443180 0000000000000000 dead000000000001
head: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea000095e201 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6019, tgid 6019 (syz-executor), ts 135767389421, free_ts 134921024956
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1af/0x220 mm/page_alloc.c:1845
 prep_new_page mm/page_alloc.c:1853 [inline]
 get_page_from_freelist+0xd0b/0x31a0 mm/page_alloc.c:3879
 __alloc_frozen_pages_noprof+0x25f/0x2440 mm/page_alloc.c:5178
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:3059 [inline]
 allocate_slab mm/slub.c:3232 [inline]
 new_slab+0x24a/0x360 mm/slub.c:3286
 ___slab_alloc+0xee7/0x1cd0 mm/slub.c:4655
 __slab_alloc.constprop.0+0x63/0x110 mm/slub.c:4778
 __slab_alloc_node mm/slub.c:4854 [inline]
 slab_alloc_node mm/slub.c:5276 [inline]
 __do_kmalloc_node mm/slub.c:5649 [inline]
 __kmalloc_noprof+0x501/0x870 mm/slub.c:5662
 kmalloc_noprof include/linux/slab.h:961 [inline]
 kmalloc_array_noprof include/linux/slab.h:1003 [inline]
 cache_create_net+0x9d/0x220 net/sunrpc/cache.c:1747
 rsc_cache_create_net net/sunrpc/auth_gss/svcauth_gss.c:2053 [inline]
 gss_svc_init_net+0x69/0x660 net/sunrpc/auth_gss/svcauth_gss.c:2081
 ops_init+0x1e2/0x5f0 net/core/net_namespace.c:137
 setup_net+0x11d/0x3a0 net/core/net_namespace.c:445
 copy_net_ns+0x351/0x5d0 net/core/net_namespace.c:580
 create_new_namespaces+0x3ea/0xab0 kernel/nsproxy.c:130
 unshare_nsproxy_namespaces+0xc0/0x1f0 kernel/nsproxy.c:226
 ksys_unshare+0x45b/0xa40 kernel/fork.c:3129
page last free pid 6002 tgid 6002 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0x7df/0x1160 mm/page_alloc.c:2901
 __folio_put+0x329/0x450 mm/swap.c:112
 folio_put include/linux/mm.h:1425 [inline]
 put_page+0x209/0x270 include/linux/mm.h:1494
 put_netmem net/core/skbuff.c:7376 [inline]
 skb_page_unref include/linux/skbuff_ref.h:43 [inline]
 __skb_frag_unref include/linux/skbuff_ref.h:56 [inline]
 skb_release_data+0x459/0x7a0 net/core/skbuff.c:1081
 skb_release_all net/core/skbuff.c:1152 [inline]
 __kfree_skb net/core/skbuff.c:1166 [inline]
 napi_consume_skb+0x1b7/0x220 net/core/skbuff.c:1476
 skb_defer_free_flush+0x1e2/0x280 net/core/dev.c:6735
 net_rx_action+0x3b3/0xfe0 net/core/dev.c:7765
 handle_softirqs+0x219/0x8b0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x109/0x170 kernel/softirq.c:723
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:739
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1056 [inline]
 sysvec_apic_timer_interrupt+0x57/0xc0 arch/x86/kernel/apic/apic.c:1056
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:697

Memory state around the buggy address:
 ffff888025788600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888025788680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888025788700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                           ^
 ffff888025788780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888025788800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================