Extracting prog: 29m4.15273345s
Minimizing prog: 25m13.71143264s
Simplifying prog options: 0s
Extracting C: 2m13.632399735s
Simplifying C: 15m30.263658658s


extracting reproducer from 37 programs
testing a last program of every proc
single: executing 7 programs separately with timeout 6m0s
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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}}): pipe-socket$inet_udp-close-socketpair$unix-socketpair$unix-recvmmsg-write$binfmt_misc-setsockopt$sock_int-splice
detailed listing:
executing program 0:
pipe(&(0x7f0000000140)={<r0=>0xffffffffffffffff})
r1 = socket$inet_udp(0x2, 0x2, 0x0)
close(r1)
socketpair$unix(0x1, 0x1, 0x0, &(0x7f0000000000)={0xffffffffffffffff, <r2=>0xffffffffffffffff})
socketpair$unix(0x1, 0x3, 0x0, 0x0)
recvmmsg(r2, &(0x7f0000001440)=[{{&(0x7f0000000280)=@un=@abs, 0x80, &(0x7f0000001400)=[{&(0x7f0000001480)=""/1, 0x1}, {&(0x7f0000000300)=""/102, 0x66}, {&(0x7f0000000380)=""/4096, 0x1000}, {0x0}], 0x4}}], 0x1, 0x40002002, 0x0)
write$binfmt_misc(r1, &(0x7f0000000040), 0xffc1)
setsockopt$sock_int(r2, 0x1, 0x10, &(0x7f0000000180)=0x55b7, 0x4)
splice(r0, 0x0, r1, 0x0, 0x4ffe0, 0x0)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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}}): ioctl$sock_ipv6_tunnel_SIOCGETTUNNEL-socket-socketpair$unix-connect$unix-sendmmsg$unix-recvmmsg-prctl$PR_SCHED_CORE-sched_setattr-mlock-ioctl$VIDIOC_CREATE_BUFS-openat$rtc-ioctl$RTC_ALM_SET-sendmsg$nl_route_sched-socket$inet6_mptcp-setsockopt$inet6_tcp_TCP_CONGESTION-bind$inet6-connect$inet6-sendmmsg$inet6-setsockopt$inet6_tcp_TCP_CONGESTION-syz_open_dev$vim2m-ioctl$vim2m_VIDIOC_REQBUFS-ioctl$vim2m_VIDIOC_PREPARE_BUF-socketpair$unix-fsopen-fsconfig$FSCONFIG_SET_STRING
detailed listing:
executing program 0:
ioctl$sock_ipv6_tunnel_SIOCGETTUNNEL(0xffffffffffffffff, 0x89f0, 0x0)
socket(0xa, 0x3, 0x3a)
socketpair$unix(0x1, 0x3, 0x0, &(0x7f0000000080)={<r0=>0xffffffffffffffff, <r1=>0xffffffffffffffff})
connect$unix(r0, &(0x7f000057eff8)=@abs, 0x6e)
sendmmsg$unix(r1, 0x0, 0x0, 0x0)
recvmmsg(r0, &(0x7f00000000c0), 0x10106, 0x2, 0x0)
prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0)
sched_setattr(0x0, &(0x7f0000000280)={0x38, 0x5, 0x8, 0x8001, 0x0, 0x9, 0x0, 0xfffffe0000000001, 0xfa11, 0xffffffff}, 0x0)
mlock(&(0x7f0000000000/0x800000)=nil, 0x800000)
ioctl$VIDIOC_CREATE_BUFS(0xffffffffffffffff, 0xc100565c, 0x0)
r2 = openat$rtc(0xffffffffffffff9c, &(0x7f0000000280), 0x40000, 0x0)
ioctl$RTC_ALM_SET(r2, 0x40247007, &(0x7f00000002c0)={0x26, 0x10, 0x3, 0xb, 0x4, 0x2, 0x3, 0x84})
sendmsg$nl_route_sched(0xffffffffffffffff, 0x0, 0x0)
r3 = socket$inet6_mptcp(0xa, 0x1, 0x106)
setsockopt$inet6_tcp_TCP_CONGESTION(r3, 0x6, 0xd, &(0x7f0000000080)='cdg\x00', 0x4)
bind$inet6(r3, &(0x7f0000000000)={0xa, 0x3, 0x0, @loopback}, 0x1c)
connect$inet6(r3, 0x0, 0x0)
sendmmsg$inet6(r3, &(0x7f0000000e40)=[{{0x0, 0x0, &(0x7f0000002c40)=[{&(0x7f00000002c0)=';', 0x1}], 0x1}}], 0x1, 0x10)
setsockopt$inet6_tcp_TCP_CONGESTION(r3, 0x6, 0xd, 0x0, 0x0)
r4 = syz_open_dev$vim2m(&(0x7f00000001c0), 0x1, 0x2)
ioctl$vim2m_VIDIOC_REQBUFS(r4, 0xc0145608, &(0x7f0000000140)={0x7, 0x1, 0x2})
ioctl$vim2m_VIDIOC_PREPARE_BUF(r4, 0xc058565d, &(0x7f0000002dc0)=@multiplanar_userptr={0x0, 0x1, 0x4, 0x0, 0x7, {0x77359400}, {0x0, 0x0, 0x0, 0x0, 0x20, 0x0, "488dc807"}, 0x1006, 0x2, {0x0}, 0x10000003})
socketpair$unix(0x1, 0x5, 0x0, 0x0)
r5 = fsopen(&(0x7f0000000040)='ceph\x00', 0x0)
fsconfig$FSCONFIG_SET_STRING(r5, 0x1, &(0x7f0000000140)='source\x00\xb5\x838\x8d\xbd\xdf\xfe\x9a\xf2RM\xb6\xe0\xf9\xac\xa2\x06\x1cD\xe7C\xa5<\xd1=\x93\xf7\xf7Sn\xcb\xd5\xa7\xc9@D\x81\xff\xaar\xc8\xa9\x13\b\x9a\x8bF\v\x8a\x93F\x00\x00\x00\x00\x00\x00\x00\x00\x00', &(0x7f00000001c0)='.\n#)|.\x02\xd8\b\xb2f\xcd\x04\xb9\xc7\x9d\xb2a\r\xd7\xef\xc5\x112s\x88\x06\x13o\xd6w\xbf\xfa\xd5?\xa3\'\xca%\xd0\x8fKAq\x89f\xbb\x9dC\xd6\xea\xa8\xc2z\xbfe\xadSb3L)Hy\xfao\b\xa4\xb6\xff\xff\xff\xff\xff\xff\xff\xf7\xc7\xa4\xdcY\x9aM\x90\xa4\x05\xa8\xec\xf3\xa4h\x11\x19\x87E$\n://\xf3\x96\xaf\x1c8\b\x84x\'+\xd5\xd4?[e\x19\xa3\\J\xe9\x8a\xb9\xe495/\x00d\xd2\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xf0\xb7\x1e\xf7Ys#m\xd40\xceP\xdc\x15FI>\x01\xfa\x15\x93\x9a&\xb4):\xc7?\x8d\x8e\x02\xc6\xf61\xbd\xbcBq\xba\xc6\x8e\x89\x15UTaf\xfc\x89\xab\x19\xd7\x82\x16\x94m\x0e\xb7$\x8c\xd76K\xdc\xd1;\\QPh@$\x06F\x81\xc9\xf8\xf8H\xb2\x85\xa8Cl\xa6\xcd\xb5\xf0\xd0\x1f\'\xc30]\xad7\x1eZA7\x89\xf5\x81b\r\xc1\x7f[\x84y\xac\x12\xaa\xa2-t\x16>V\xfc\xbf\xdb\xe4\x9a\x9eE^\x90oe\xc0\xd9\xc68\x0f\xd4\xcdKC\xadp\xba\xaa\xab\'\x1cRO\x89\x17i\x88\"\x8dQI\xed\x1d\xe1v\xe6&\xd3\x14\xe92\xca\x9dBe\\\x8f\xff\x9b\xc7Sd!\xf8(Z\xd42\xa2\xcdjjBP\xae3\xbd\xec\x8a\x8f:\xeb1\x1cK\xf2\x04s\b\xcb\xa9\x17\x8529\xd7`\v\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\xf1\xa4C\x81\xc8iy\xc4\xf7\x7f\x90\xf80\x18jT\xd45\xde\b\x88\xc9Xw\xe9\xf4\xa4\x94Q\x03s/\xac\xd4\xb7o\x99\xf5\xdb\xf9\x99,+\b\x17\xe4\xf4r}\xda\xf5\x12\x16\xb6g\x00\'(\x02[\xef\x03\x90W% \xe6b\xa2\\\x86\xac\xdax\x997AOJ=\x1f\x00\xe1/\n\xael\x15\xcfR\v\x0e\xbc!\xe8\x1cV-`\xf0$\xa6a \x93PV\x8dm@\x9c', 0x0)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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$uac1-syz_usb_control_io$printer-syz_usb_control_io$printer-syz_usb_control_io-syz_usb_control_io-syz_usb_control_io$hid
detailed listing:
executing program 0:
r0 = syz_usb_connect(0x0, 0x36, &(0x7f0000000040)=ANY=[@ANYBLOB="12010000f2303920422c02124085010203010902240009040c"], 0x0)
syz_usb_control_io$uac1(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io(r0, 0x0, 0x0)
syz_usb_control_io(r0, 0x0, 0x0)
syz_usb_control_io$hid(r0, 0x0, 0x0)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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}}): socket$inet6-prlimit64-sched_setscheduler-sched_setaffinity-prctl$PR_SCHED_CORE-syz_open_dev$MSR-read$msr-syz_open_dev$usbfs-socket$nl_netfilter-ioctl$USBDEVFS_CONTROL-setsockopt$SO_TIMESTAMPING-bpf$MAP_UPDATE_ELEM
detailed listing:
executing program 0:
r0 = socket$inet6(0xa, 0x800000000000002, 0x0)
prlimit64(0x0, 0xe, &(0x7f0000000140)={0x8, 0x8b}, 0x0)
sched_setscheduler(0x0, 0x2, &(0x7f0000000100)=0x5)
sched_setaffinity(0x0, 0xff43, &(0x7f00000002c0)=0x2)
prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x2, 0x0)
r1 = syz_open_dev$MSR(&(0x7f00000007c0), 0x0, 0x0)
read$msr(r1, &(0x7f0000019680)=""/102392, 0x18ff8)
r2 = syz_open_dev$usbfs(&(0x7f0000003f00), 0x1ff, 0xa401)
socket$nl_netfilter(0x10, 0x3, 0xc)
ioctl$USBDEVFS_CONTROL(r2, 0xc0185500, &(0x7f00000006c0)={0x5, 0xf, 0x4, 0x11, 0x0, 0x5, 0x0})
setsockopt$SO_TIMESTAMPING(r0, 0x1, 0x41, &(0x7f0000000200)=0x632a, 0x4)
bpf$MAP_UPDATE_ELEM(0x2, &(0x7f0000000340)={0xffffffffffffffff, &(0x7f00000001c0), &(0x7f0000000280)=@udp}, 0x20)

program did not crash
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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$printer-syz_usb_control_io$printer-syz_usb_control_io$lan78xx-syz_usb_control_io$cdc_ncm-syz_usb_control_io$hid-syz_usb_control_io$cdc_ncm-syz_usb_control_io$printer-syz_usb_control_io$hid-syz_usb_control_io$hid
detailed listing:
executing program 0:
r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$lan78xx(r0, 0x0, 0x0)
syz_usb_control_io$cdc_ncm(r0, 0x0, 0x0)
syz_usb_control_io$hid(r0, 0x0, &(0x7f0000000cc0)={0x2c, &(0x7f0000000d00)=ANY=[], 0x0, 0x0, 0x0, 0x0})
syz_usb_control_io$cdc_ncm(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, &(0x7f0000000580)={0x34, &(0x7f0000000180)={0x20, 0x14}, 0x0, 0x0, 0x0, 0x0, 0x0})
syz_usb_control_io$hid(r0, 0x0, &(0x7f0000000540)={0x2c, &(0x7f00000002c0)={0x0, 0x14}, 0x0, 0x0, 0x0, 0x0})
syz_usb_control_io$hid(r0, 0x0, 0x0)

program crashed: KASAN: use-after-free Read in v4l2_fh_open
single: successfully extracted reproducer
found reproducer with 10 syscalls
minimizing guilty program
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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$printer-syz_usb_control_io$printer-syz_usb_control_io$lan78xx-syz_usb_control_io$cdc_ncm-syz_usb_control_io$hid-syz_usb_control_io$cdc_ncm-syz_usb_control_io$printer-syz_usb_control_io$hid
detailed listing:
executing program 0:
r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$lan78xx(r0, 0x0, 0x0)
syz_usb_control_io$cdc_ncm(r0, 0x0, 0x0)
syz_usb_control_io$hid(r0, 0x0, &(0x7f0000000cc0)={0x2c, &(0x7f0000000d00)=ANY=[], 0x0, 0x0, 0x0, 0x0})
syz_usb_control_io$cdc_ncm(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, &(0x7f0000000580)={0x34, &(0x7f0000000180)={0x20, 0x14}, 0x0, 0x0, 0x0, 0x0, 0x0})
syz_usb_control_io$hid(r0, 0x0, &(0x7f0000000540)={0x2c, &(0x7f00000002c0)={0x0, 0x14}, 0x0, 0x0, 0x0, 0x0})

program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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$printer-syz_usb_control_io$printer-syz_usb_control_io$lan78xx-syz_usb_control_io$cdc_ncm-syz_usb_control_io$hid-syz_usb_control_io$cdc_ncm-syz_usb_control_io$printer
detailed listing:
executing program 0:
r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$lan78xx(r0, 0x0, 0x0)
syz_usb_control_io$cdc_ncm(r0, 0x0, 0x0)
syz_usb_control_io$hid(r0, 0x0, &(0x7f0000000cc0)={0x2c, &(0x7f0000000d00)=ANY=[], 0x0, 0x0, 0x0, 0x0})
syz_usb_control_io$cdc_ncm(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, &(0x7f0000000580)={0x34, &(0x7f0000000180)={0x20, 0x14}, 0x0, 0x0, 0x0, 0x0, 0x0})

program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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$printer-syz_usb_control_io$printer-syz_usb_control_io$lan78xx-syz_usb_control_io$cdc_ncm-syz_usb_control_io$hid-syz_usb_control_io$cdc_ncm
detailed listing:
executing program 0:
r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$lan78xx(r0, 0x0, 0x0)
syz_usb_control_io$cdc_ncm(r0, 0x0, 0x0)
syz_usb_control_io$hid(r0, 0x0, &(0x7f0000000cc0)={0x2c, &(0x7f0000000d00)=ANY=[], 0x0, 0x0, 0x0, 0x0})
syz_usb_control_io$cdc_ncm(r0, 0x0, 0x0)

program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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$printer-syz_usb_control_io$printer-syz_usb_control_io$lan78xx-syz_usb_control_io$cdc_ncm-syz_usb_control_io$hid
detailed listing:
executing program 0:
r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$lan78xx(r0, 0x0, 0x0)
syz_usb_control_io$cdc_ncm(r0, 0x0, 0x0)
syz_usb_control_io$hid(r0, 0x0, &(0x7f0000000cc0)={0x2c, &(0x7f0000000d00)=ANY=[], 0x0, 0x0, 0x0, 0x0})

program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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$printer-syz_usb_control_io$printer-syz_usb_control_io$lan78xx-syz_usb_control_io$cdc_ncm
detailed listing:
executing program 0:
r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$lan78xx(r0, 0x0, 0x0)
syz_usb_control_io$cdc_ncm(r0, 0x0, 0x0)

program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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$printer-syz_usb_control_io$printer-syz_usb_control_io$lan78xx
detailed listing:
executing program 0:
r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$lan78xx(r0, 0x0, 0x0)

program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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$printer-syz_usb_control_io$printer
detailed listing:
executing program 0:
r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)

program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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$printer
detailed listing:
executing program 0:
r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)
syz_usb_control_io$printer(r0, 0x0, 0x0)

program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)

program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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(0x0, 0x0, 0x0, 0x0)

program did not crash
extracting C reproducer
testing compiled C program (duration=6m0s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 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
program crashed: KASAN: use-after-free Read in v4l2_fh_open
simplifying C reproducer
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 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
program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing compiled C program (duration=6m0s, {Threaded:false 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
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:false 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: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
program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing compiled C program (duration=6m0s, {Threaded:false 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: KASAN: use-after-free Read in v4l2_fh_open
testing compiled C program (duration=6m0s, {Threaded:false 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:false 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 v4l2_fh_open
testing compiled C program (duration=6m0s, {Threaded:false 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:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing compiled C program (duration=6m0s, {Threaded:false 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:false Swap:false UseTmpDir:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: use-after-free Read in v4l2_fh_open
testing program (duration=6m0s, {Threaded:false 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:false Swap:false UseTmpDir:false HandleSegv:false 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, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)

program crashed: KASAN: use-after-free Read in v4l2_fh_open
validation run: crashed=true
testing program (duration=6m0s, {Threaded:false 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:false Swap:false UseTmpDir:false HandleSegv:false 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, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)

program crashed: KASAN: use-after-free Read in v4l2_fh_open
validation run: crashed=true
testing program (duration=6m0s, {Threaded:false 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:false Swap:false UseTmpDir:false HandleSegv:false 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, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0)

program crashed: KASAN: use-after-free Read in v4l2_fh_open
validation run: crashed=true
reproducing took 1h17m59.695685291s
repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: use-after-free in v4l2_fh_init drivers/media/v4l2-core/v4l2-fh.c:25 [inline]
BUG: KASAN: use-after-free in v4l2_fh_open+0xc6/0x430 drivers/media/v4l2-core/v4l2-fh.c:63
Read of size 8 at addr ffff88805cf80738 by task v4l_id/4591

CPU: 1 PID: 4591 Comm: v4l_id Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0xa8/0x210 mm/kasan/report.c:420
 kasan_report+0x10b/0x140 mm/kasan/report.c:524
 v4l2_fh_init drivers/media/v4l2-core/v4l2-fh.c:25 [inline]
 v4l2_fh_open+0xc6/0x430 drivers/media/v4l2-core/v4l2-fh.c:63
 em28xx_v4l2_open+0x152/0x990 drivers/media/usb/em28xx/em28xx-video.c:2153
 v4l2_open+0x20b/0x360 drivers/media/v4l2-core/v4l2-dev.c:427
 chrdev_open+0x597/0x670 fs/char_dev.c:414
 do_dentry_open+0x7e9/0x10d0 fs/open.c:882
 do_open fs/namei.c:3626 [inline]
 path_openat+0x25c6/0x2e70 fs/namei.c:3783
 do_filp_open+0x1c1/0x3c0 fs/namei.c:3810
 do_sys_openat2+0x142/0x490 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1345
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa0f68a7407
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:00007ffeed88e5f0 EFLAGS: 00000202
 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa0f6f65880 RCX: 00007fa0f68a7407
RDX: 0000000000000000 RSI: 00007ffeed88ef1c RDI: ffffffffffffff9c
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffeed88e840 R14: 00007fa0f70c4000 R15: 00005622f4beb4d8
 </TASK>

Allocated by task 14:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:563 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 em28xx_v4l2_init+0x107/0x2e70 drivers/media/usb/em28xx/em28xx-video.c:2532
 em28xx_init_extension+0x118/0x1b0 drivers/media/usb/em28xx/em28xx-core.c:1116
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 14:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700
 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2118 [inline]
 kref_put include/linux/kref.h:65 [inline]
 em28xx_v4l2_init+0x166c/0x2e70 drivers/media/usb/em28xx/em28xx-video.c:2901
 em28xx_init_extension+0x118/0x1b0 drivers/media/usb/em28xx/em28xx-core.c:1116
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff88805cf80000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 1848 bytes inside of
 8192-byte region [ffff88805cf80000, ffff88805cf82000)

The buggy address belongs to the physical page:
page:ffffea000173e000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5cf80
head:ffffea000173e000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001d26600 dead000000000006 ffff888017442280
raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4330, tgid 4330 (syz-executor), ts 85447362916, free_ts 85427637976
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328
 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614
 alloc_slab_page+0x5d/0x160 mm/slub.c:1799
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x87/0x2c0 mm/slub.c:1997
 ___slab_alloc+0xbc6/0x1230 mm/slub.c:3154
 __slab_alloc mm/slub.c:3240 [inline]
 slab_alloc_node mm/slub.c:3325 [inline]
 __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa0/0x240 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 ops_init+0x8b/0x5f0 net/core/net_namespace.c:128
 setup_net+0x4e1/0xbb0 net/core/net_namespace.c:336
 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:508
 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x116/0x160 kernel/nsproxy.c:226
 ksys_unshare+0x4bc/0x890 kernel/fork.c:3277
 __do_sys_unshare kernel/fork.c:3348 [inline]
 __se_sys_unshare kernel/fork.c:3346 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3346
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1459 [inline]
 free_pcp_prepare mm/page_alloc.c:1509 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479
 __vunmap+0x856/0xa00 mm/vmalloc.c:2726
 kcov_put kernel/kcov.c:437 [inline]
 kcov_close+0x27/0x50 kernel/kcov.c:533
 __fput+0x22c/0x920 fs/file_table.c:320
 task_work_run+0x1ca/0x250 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0x93e/0x2400 kernel/exit.c:880
 do_group_exit+0x217/0x2d0 kernel/exit.c:1022
 get_signal+0x1272/0x1350 kernel/signal.c:2871
 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff88805cf80600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805cf80680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805cf80700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff88805cf80780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805cf80800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

final repro crashed as (corrupted=false):
==================================================================
BUG: KASAN: use-after-free in v4l2_fh_init drivers/media/v4l2-core/v4l2-fh.c:25 [inline]
BUG: KASAN: use-after-free in v4l2_fh_open+0xc6/0x430 drivers/media/v4l2-core/v4l2-fh.c:63
Read of size 8 at addr ffff88805cf80738 by task v4l_id/4591

CPU: 1 PID: 4591 Comm: v4l_id Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0xa8/0x210 mm/kasan/report.c:420
 kasan_report+0x10b/0x140 mm/kasan/report.c:524
 v4l2_fh_init drivers/media/v4l2-core/v4l2-fh.c:25 [inline]
 v4l2_fh_open+0xc6/0x430 drivers/media/v4l2-core/v4l2-fh.c:63
 em28xx_v4l2_open+0x152/0x990 drivers/media/usb/em28xx/em28xx-video.c:2153
 v4l2_open+0x20b/0x360 drivers/media/v4l2-core/v4l2-dev.c:427
 chrdev_open+0x597/0x670 fs/char_dev.c:414
 do_dentry_open+0x7e9/0x10d0 fs/open.c:882
 do_open fs/namei.c:3626 [inline]
 path_openat+0x25c6/0x2e70 fs/namei.c:3783
 do_filp_open+0x1c1/0x3c0 fs/namei.c:3810
 do_sys_openat2+0x142/0x490 fs/open.c:1318
 do_sys_open fs/open.c:1334 [inline]
 __do_sys_openat fs/open.c:1350 [inline]
 __se_sys_openat fs/open.c:1345 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1345
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa0f68a7407
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:00007ffeed88e5f0 EFLAGS: 00000202
 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fa0f6f65880 RCX: 00007fa0f68a7407
RDX: 0000000000000000 RSI: 00007ffeed88ef1c RDI: ffffffffffffff9c
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffeed88e840 R14: 00007fa0f70c4000 R15: 00005622f4beb4d8
 </TASK>

Allocated by task 14:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:563 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 em28xx_v4l2_init+0x107/0x2e70 drivers/media/usb/em28xx/em28xx-video.c:2532
 em28xx_init_extension+0x118/0x1b0 drivers/media/usb/em28xx/em28xx-core.c:1116
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 14:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700
 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2118 [inline]
 kref_put include/linux/kref.h:65 [inline]
 em28xx_v4l2_init+0x166c/0x2e70 drivers/media/usb/em28xx/em28xx-video.c:2901
 em28xx_init_extension+0x118/0x1b0 drivers/media/usb/em28xx/em28xx-core.c:1116
 process_one_work+0x898/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff88805cf80000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 1848 bytes inside of
 8192-byte region [ffff88805cf80000, ffff88805cf82000)

The buggy address belongs to the physical page:
page:ffffea000173e000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5cf80
head:ffffea000173e000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001d26600 dead000000000006 ffff888017442280
raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4330, tgid 4330 (syz-executor), ts 85447362916, free_ts 85427637976
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532
 prep_new_page mm/page_alloc.c:2539 [inline]
 get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328
 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614
 alloc_slab_page+0x5d/0x160 mm/slub.c:1799
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x87/0x2c0 mm/slub.c:1997
 ___slab_alloc+0xbc6/0x1230 mm/slub.c:3154
 __slab_alloc mm/slub.c:3240 [inline]
 slab_alloc_node mm/slub.c:3325 [inline]
 __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc+0xa0/0x240 mm/slab_common.c:949
 kmalloc include/linux/slab.h:568 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 ops_init+0x8b/0x5f0 net/core/net_namespace.c:128
 setup_net+0x4e1/0xbb0 net/core/net_namespace.c:336
 copy_net_ns+0x348/0x5b0 net/core/net_namespace.c:508
 create_new_namespaces+0x3d3/0x6f0 kernel/nsproxy.c:110
 unshare_nsproxy_namespaces+0x116/0x160 kernel/nsproxy.c:226
 ksys_unshare+0x4bc/0x890 kernel/fork.c:3277
 __do_sys_unshare kernel/fork.c:3348 [inline]
 __se_sys_unshare kernel/fork.c:3346 [inline]
 __x64_sys_unshare+0x34/0x40 kernel/fork.c:3346
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1459 [inline]
 free_pcp_prepare mm/page_alloc.c:1509 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479
 __vunmap+0x856/0xa00 mm/vmalloc.c:2726
 kcov_put kernel/kcov.c:437 [inline]
 kcov_close+0x27/0x50 kernel/kcov.c:533
 __fput+0x22c/0x920 fs/file_table.c:320
 task_work_run+0x1ca/0x250 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0x93e/0x2400 kernel/exit.c:880
 do_group_exit+0x217/0x2d0 kernel/exit.c:1022
 get_signal+0x1272/0x1350 kernel/signal.c:2871
 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871
 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Memory state around the buggy address:
 ffff88805cf80600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805cf80680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88805cf80700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                        ^
 ffff88805cf80780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88805cf80800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================