Extracting prog: 8m54.350920745s Minimizing prog: 14m52.000658048s Simplifying prog options: 0s Extracting C: 46.310901456s Simplifying C: 13m39.584576363s extracting reproducer from 34 programs testing a last program of every proc single: executing 8 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}}): bpf$MAP_CREATE-prctl$PR_SCHED_CORE-syz_open_dev$MSR-socket$inet6-socket$inet6_tcp-sendmmsg$inet6-mprotect-socket$inet6-connect$inet6-sendmmsg$inet6 detailed listing: executing program 0: bpf$MAP_CREATE(0x0, 0x0, 0x50) prctl$PR_SCHED_CORE(0x3e, 0x1, 0x0, 0x1, 0x0) syz_open_dev$MSR(0x0, 0x0, 0x0) socket$inet6(0xa, 0x80002, 0x0) r0 = socket$inet6_tcp(0xa, 0x1, 0x0) sendmmsg$inet6(r0, &(0x7f00000001c0)=[{{&(0x7f0000000000)={0xa, 0x4e22, 0x1, @local, 0xa}, 0x1c, 0x0}}], 0x1, 0x20084800) mprotect(&(0x7f0000000000/0x3000)=nil, 0x3000, 0x1) r1 = socket$inet6(0xa, 0x80002, 0x0) connect$inet6(r1, &(0x7f0000000000)={0xa, 0x4e22, 0x0, @dev, 0x5}, 0x1c) sendmmsg$inet6(r1, &(0x7f0000003cc0)=[{{0x0, 0x0, &(0x7f0000003980), 0x171}}], 0x400000000000172, 0x4000000) 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$uac1-syz_usb_control_io$printer-syz_usb_control_io$hid-syz_usb_control_io$cdc_ecm-syz_usb_control_io$hid detailed listing: executing program 0: r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0) syz_usb_control_io$uac1(r0, 0x0, 0x0) syz_usb_control_io$printer(r0, 0x0, 0x0) syz_usb_control_io$hid(r0, 0x0, 0x0) syz_usb_control_io$cdc_ecm(r0, 0x0, 0x0) syz_usb_control_io$hid(r0, 0x0, &(0x7f0000000540)={0x18, &(0x7f00000003c0)={0x40, 0x18, 0x2, '\to'}, 0x0, 0x0, 0x0, 0x0}) program crashed: KASAN: slab-use-after-free Read in v4l2_fh_open single: successfully extracted reproducer found reproducer with 6 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$uac1-syz_usb_control_io$printer-syz_usb_control_io$hid-syz_usb_control_io$cdc_ecm 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$uac1(r0, 0x0, 0x0) syz_usb_control_io$printer(r0, 0x0, 0x0) syz_usb_control_io$hid(r0, 0x0, 0x0) syz_usb_control_io$cdc_ecm(r0, 0x0, 0x0) program crashed: KASAN: slab-use-after-free Read in v4l2_fh_open 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$uac1-syz_usb_control_io$printer-syz_usb_control_io$hid detailed listing: executing program 0: r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0) syz_usb_control_io$uac1(r0, 0x0, 0x0) syz_usb_control_io$printer(r0, 0x0, 0x0) syz_usb_control_io$hid(r0, 0x0, 0x0) program crashed: KASAN: slab-use-after-free Read in v4l2_fh_open 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$uac1-syz_usb_control_io$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$uac1(r0, 0x0, 0x0) syz_usb_control_io$printer(r0, 0x0, 0x0) program crashed: KASAN: slab-use-after-free Read in v4l2_fh_open 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$uac1 detailed listing: executing program 0: r0 = syz_usb_connect(0x0, 0x2d, &(0x7f0000000600)={{0x12, 0x1, 0x0, 0x35, 0xff, 0xaa, 0x20, 0xccd, 0x10af, 0x384e, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x1b, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x59, 0x2, 0x1, 0x9b, 0x1e, 0x2a, 0x0, [], [{{0x9, 0x5, 0x82, 0x2, 0x200}}]}}]}}]}}, 0x0) syz_usb_control_io$uac1(r0, 0x0, 0x0) program crashed: KASAN: slab-use-after-free Read in v4l2_fh_open 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(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: slab-use-after-free Read in v4l2_fh_open 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(0x0, 0x0, 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 program crashed: KASAN: slab-use-after-free Read in v4l2_fh_open 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 program crashed: KASAN: slab-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: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 program crashed: KASAN: slab-use-after-free Read in v4l2_fh_open testing compiled C program (duration=6m0s, {Threaded:false 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 program crashed: KASAN: slab-use-after-free Read in v4l2_fh_open testing compiled C program (duration=6m0s, {Threaded:false 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:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect program crashed: KASAN: slab-use-after-free Read in v4l2_fh_open testing compiled C program (duration=6m0s, {Threaded:false 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:false HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect program crashed: KASAN: slab-use-after-free Read in v4l2_fh_open testing compiled C program (duration=6m0s, {Threaded:false 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: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: slab-use-after-free Read in v4l2_fh_open testing program (duration=6m0s, {Threaded:false 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: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: slab-use-after-free Read in v4l2_fh_open validation run: crashed=true testing program (duration=6m0s, {Threaded:false 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: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: slab-use-after-free Read in v4l2_fh_open validation run: crashed=true testing program (duration=6m0s, {Threaded:false 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: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: slab-use-after-free Read in v4l2_fh_open validation run: crashed=true reproducing took 44m12.871479329s repro crashed as (corrupted=false): ================================================================== BUG: KASAN: slab-use-after-free in v4l2_fh_init drivers/media/v4l2-core/v4l2-fh.c:25 [inline] BUG: KASAN: slab-use-after-free in v4l2_fh_open+0xca/0x430 drivers/media/v4l2-core/v4l2-fh.c:63 Read of size 8 at addr ffff88802fd7c738 by task v4l_id/6044 CPU: 1 PID: 6044 Comm: v4l_id Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x220 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 v4l2_fh_init drivers/media/v4l2-core/v4l2-fh.c:25 [inline] v4l2_fh_open+0xca/0x430 drivers/media/v4l2-core/v4l2-fh.c:63 em28xx_v4l2_open+0x157/0x980 drivers/media/usb/em28xx/em28xx-video.c:2153 v4l2_open+0x212/0x360 drivers/media/v4l2-core/v4l2-dev.c:427 chrdev_open+0x59e/0x670 fs/char_dev.c:414 do_dentry_open+0x8c6/0x1500 fs/open.c:929 do_open fs/namei.c:3632 [inline] path_openat+0x274b/0x3190 fs/namei.c:3789 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419 do_sys_open fs/open.c:1434 [inline] __do_sys_openat fs/open.c:1450 [inline] __se_sys_openat fs/open.c:1445 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1445 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f6498ea7407 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:00007fff0c29f150 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f6499612880 RCX: 00007f6498ea7407 RDX: 0000000000000000 RSI: 00007fff0c29ff1c RDI: ffffffffffffff9c RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 00007fff0c29f3a0 R14: 00007f6499771000 R15: 00005555783b64d8 Allocated by task 785: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] em28xx_v4l2_init+0x10b/0x2e70 drivers/media/usb/em28xx/em28xx-video.c:2532 em28xx_init_extension+0x11c/0x1b0 drivers/media/usb/em28xx/em28xx-core.c:1116 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Freed by task 785: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3843 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2118 [inline] kref_put include/linux/kref.h:65 [inline] em28xx_v4l2_init+0x1670/0x2e70 drivers/media/usb/em28xx/em28xx-video.c:2901 em28xx_init_extension+0x11c/0x1b0 drivers/media/usb/em28xx/em28xx-core.c:1116 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88802fd7c000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 1848 bytes inside of freed 8192-byte region [ffff88802fd7c000, ffff88802fd7e000) The buggy address belongs to the physical page: page:ffffea0000bf5e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2fd78 head:ffffea0000bf5e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017842280 ffffea0000c00800 dead000000000005 raw: 0000000000000000 0000000080020002 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5448, tgid 5448 (S41dhcpcd), ts 68130837616, free_ts 68128398538 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2e0 mm/slub.c:2081 ___slab_alloc+0xc6d/0x1300 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] tomoyo_print_bprm security/tomoyo/audit.c:26 [inline] tomoyo_init_log+0x1104/0x1f10 security/tomoyo/audit.c:264 tomoyo_supervisor+0x32d/0x1080 security/tomoyo/common.c:2089 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline] tomoyo_env_perm+0x14a/0x1e0 security/tomoyo/environ.c:63 tomoyo_environ security/tomoyo/domain.c:672 [inline] tomoyo_find_next_domain+0x1594/0x1a60 security/tomoyo/domain.c:881 tomoyo_bprm_check_security+0x116/0x170 security/tomoyo/tomoyo.c:101 security_bprm_check+0x62/0xa0 security/security.c:1103 search_binary_handler fs/exec.c:1763 [inline] exec_binprm fs/exec.c:1817 [inline] bprm_execve+0xa51/0x16f0 fs/exec.c:1892 do_execveat_common+0x51b/0x6c0 fs/exec.c:1998 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 discard_slab mm/slub.c:2127 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667 put_cpu_partial+0x17c/0x250 mm/slub.c:2743 __slab_free+0x31d/0x410 mm/slub.c:3700 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] __kmem_cache_alloc_node+0x13e/0x260 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] tomoyo_add_entry security/tomoyo/common.c:2023 [inline] tomoyo_supervisor+0xb70/0x1080 security/tomoyo/common.c:2095 tomoyo_find_next_domain+0x44c/0x1a60 security/tomoyo/domain.c:755 tomoyo_bprm_check_security+0x116/0x170 security/tomoyo/tomoyo.c:101 security_bprm_check+0x62/0xa0 security/security.c:1103 search_binary_handler fs/exec.c:1763 [inline] exec_binprm fs/exec.c:1817 [inline] bprm_execve+0xa51/0x16f0 fs/exec.c:1892 Memory state around the buggy address: ffff88802fd7c600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802fd7c680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802fd7c700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802fd7c780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802fd7c800: 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 drivers/media/v4l2-core/v4l2-fh.c:25 [inline] BUG: KASAN: slab-use-after-free in v4l2_fh_open+0xca/0x430 drivers/media/v4l2-core/v4l2-fh.c:63 Read of size 8 at addr ffff88802fd7c738 by task v4l_id/6044 CPU: 1 PID: 6044 Comm: v4l_id Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x220 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 v4l2_fh_init drivers/media/v4l2-core/v4l2-fh.c:25 [inline] v4l2_fh_open+0xca/0x430 drivers/media/v4l2-core/v4l2-fh.c:63 em28xx_v4l2_open+0x157/0x980 drivers/media/usb/em28xx/em28xx-video.c:2153 v4l2_open+0x212/0x360 drivers/media/v4l2-core/v4l2-dev.c:427 chrdev_open+0x59e/0x670 fs/char_dev.c:414 do_dentry_open+0x8c6/0x1500 fs/open.c:929 do_open fs/namei.c:3632 [inline] path_openat+0x274b/0x3190 fs/namei.c:3789 do_filp_open+0x1c5/0x3d0 fs/namei.c:3816 do_sys_openat2+0x12c/0x1c0 fs/open.c:1419 do_sys_open fs/open.c:1434 [inline] __do_sys_openat fs/open.c:1450 [inline] __se_sys_openat fs/open.c:1445 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1445 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f6498ea7407 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:00007fff0c29f150 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f6499612880 RCX: 00007f6498ea7407 RDX: 0000000000000000 RSI: 00007fff0c29ff1c RDI: ffffffffffffff9c RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000 R13: 00007fff0c29f3a0 R14: 00007f6499771000 R15: 00005555783b64d8 Allocated by task 785: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] em28xx_v4l2_init+0x10b/0x2e70 drivers/media/usb/em28xx/em28xx-video.c:2532 em28xx_init_extension+0x11c/0x1b0 drivers/media/usb/em28xx/em28xx-core.c:1116 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Freed by task 785: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3843 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2118 [inline] kref_put include/linux/kref.h:65 [inline] em28xx_v4l2_init+0x1670/0x2e70 drivers/media/usb/em28xx/em28xx-video.c:2901 em28xx_init_extension+0x11c/0x1b0 drivers/media/usb/em28xx/em28xx-core.c:1116 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88802fd7c000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 1848 bytes inside of freed 8192-byte region [ffff88802fd7c000, ffff88802fd7e000) The buggy address belongs to the physical page: page:ffffea0000bf5e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2fd78 head:ffffea0000bf5e00 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017842280 ffffea0000c00800 dead000000000005 raw: 0000000000000000 0000000080020002 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 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5448, tgid 5448 (S41dhcpcd), ts 68130837616, free_ts 68128398538 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2e0 mm/slub.c:2081 ___slab_alloc+0xc6d/0x1300 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3534 kmalloc_trace+0x2a/0xe0 mm/slab_common.c:1098 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] tomoyo_print_bprm security/tomoyo/audit.c:26 [inline] tomoyo_init_log+0x1104/0x1f10 security/tomoyo/audit.c:264 tomoyo_supervisor+0x32d/0x1080 security/tomoyo/common.c:2089 tomoyo_audit_env_log security/tomoyo/environ.c:36 [inline] tomoyo_env_perm+0x14a/0x1e0 security/tomoyo/environ.c:63 tomoyo_environ security/tomoyo/domain.c:672 [inline] tomoyo_find_next_domain+0x1594/0x1a60 security/tomoyo/domain.c:881 tomoyo_bprm_check_security+0x116/0x170 security/tomoyo/tomoyo.c:101 security_bprm_check+0x62/0xa0 security/security.c:1103 search_binary_handler fs/exec.c:1763 [inline] exec_binprm fs/exec.c:1817 [inline] bprm_execve+0xa51/0x16f0 fs/exec.c:1892 do_execveat_common+0x51b/0x6c0 fs/exec.c:1998 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 discard_slab mm/slub.c:2127 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667 put_cpu_partial+0x17c/0x250 mm/slub.c:2743 __slab_free+0x31d/0x410 mm/slub.c:3700 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] __kmem_cache_alloc_node+0x13e/0x260 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x240 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] tomoyo_add_entry security/tomoyo/common.c:2023 [inline] tomoyo_supervisor+0xb70/0x1080 security/tomoyo/common.c:2095 tomoyo_find_next_domain+0x44c/0x1a60 security/tomoyo/domain.c:755 tomoyo_bprm_check_security+0x116/0x170 security/tomoyo/tomoyo.c:101 security_bprm_check+0x62/0xa0 security/security.c:1103 search_binary_handler fs/exec.c:1763 [inline] exec_binprm fs/exec.c:1817 [inline] bprm_execve+0xa51/0x16f0 fs/exec.c:1892 Memory state around the buggy address: ffff88802fd7c600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802fd7c680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802fd7c700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802fd7c780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802fd7c800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================