Extracting prog: 4m28.761856095s
Minimizing prog: 6m6.088283105s
Simplifying prog options: 0s
Extracting C: 1m47.979954041s
Simplifying C: 11m44.369900474s


extracting reproducer from 1 programs
testing a last program of every proc
single: executing 1 programs separately with timeout 30s
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
detailed listing:
executing program 0:
syz_usb_connect(0x0, 0x36, &(0x7f0000000000)={{0x12, 0x1, 0x0, 0x6e, 0xa6, 0x87, 0x20, 0x2304, 0x208, 0xe9bc, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x24, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x24, 0x2, 0x2, 0x61, 0xfe, 0x78, 0x0, [], [{{0x9, 0x5, 0x1, 0xa, 0x200, 0x5}}, {{0x9, 0x5, 0x82, 0x0, 0x200, 0x20}}]}}]}}]}}, 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:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
detailed listing:
executing program 0:
syz_usb_connect(0x0, 0x36, &(0x7f0000000000)={{0x12, 0x1, 0x0, 0x6e, 0xa6, 0x87, 0x20, 0x2304, 0x208, 0xe9bc, 0x1, 0x2, 0x3, 0x1, [{{0x9, 0x2, 0x24, 0x1, 0x0, 0x0, 0x10, 0x0, [{{0x9, 0x4, 0x24, 0x2, 0x2, 0x61, 0xfe, 0x78, 0x0, [], [{{0x9, 0x5, 0x1, 0xa, 0x200, 0x5}}, {{0x9, 0x5, 0x82, 0x0, 0x200, 0x20}}]}}]}}]}}, 0x0)

program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
single: successfully extracted reproducer
found reproducer with 1 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:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false 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:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
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:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
testing compiled C program (duration=6m0s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false 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:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
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 LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): syz_usb_connect
program crashed: KASAN: slab-use-after-free Read in v4l2_fh_init
reproducing took 24m7.200011055s
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 ffff888119cb0730 by task v4l_id/3394

CPU: 0 UID: 0 PID: 3394 Comm: v4l_id Not tainted 6.15.0-rc6-syzkaller-00177-g882826f58b2c #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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:408 [inline]
 print_report+0xc3/0x670 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 v4l2_fh_init+0x27d/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25
 v4l2_fh_open+0x83/0xc0 drivers/media/v4l2-core/v4l2-fh.c:63
 em28xx_v4l2_open+0x24e/0x7e0 drivers/media/usb/em28xx/em28xx-video.c:2153
 v4l2_open+0x222/0x490 drivers/media/v4l2-core/v4l2-dev.c:429
 chrdev_open+0x231/0x6a0 fs/char_dev.c:414
 do_dentry_open+0x6d7/0x13a0 fs/open.c:956
 vfs_open+0x82/0x3f0 fs/open.c:1086
 do_open fs/namei.c:3880 [inline]
 path_openat+0x1e5e/0x2d40 fs/namei.c:4039
 do_filp_open+0x20b/0x470 fs/namei.c:4066
 do_sys_openat2+0x11b/0x1d0 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_sys_openat fs/open.c:1460 [inline]
 __se_sys_openat fs/open.c:1455 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1455
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9ae5108407
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:00007fff617310e0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f9ae501a880 RCX: 00007f9ae5108407
RDX: 0000000000000000 RSI: 00007fff61731f26 RDI: ffffffffffffff9c
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fff61731330 R14: 00007f9ae589e000 R15: 00005600ec2484d8
 </TASK>

Allocated by task 2975:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:394
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 em28xx_v4l2_init+0x114/0x40c0 drivers/media/usb/em28xx/em28xx-video.c:2532
 em28xx_init_extension+0x137/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117
 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 2975:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x37/0x50 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2380 [inline]
 slab_free mm/slub.c:4642 [inline]
 kfree+0x286/0x470 mm/slub.c:4841
 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2118 [inline]
 kref_put include/linux/kref.h:65 [inline]
 em28xx_v4l2_init+0x22c5/0x40c0 drivers/media/usb/em28xx/em28xx-video.c:2901
 em28xx_init_extension+0x137/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117
 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff888119cb0000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 1840 bytes inside of
 freed 8192-byte region [ffff888119cb0000, ffff888119cb2000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x119cb0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff888100042280 0000000000000000 0000000000000001
raw: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 0200000000000040 ffff888100042280 0000000000000000 0000000000000001
head: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 0200000000000003 ffffea0004672c01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 2930, tgid 2930 (sshd-session), ts 27108167435, free_ts 27002668038
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1718
 prep_new_page mm/page_alloc.c:1726 [inline]
 get_page_from_freelist+0xfec/0x2d90 mm/page_alloc.c:3688
 __alloc_frozen_pages_noprof+0x25c/0x2160 mm/page_alloc.c:4970
 alloc_pages_mpol+0xe4/0x410 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2450 [inline]
 allocate_slab mm/slub.c:2618 [inline]
 new_slab+0x244/0x340 mm/slub.c:2672
 ___slab_alloc+0xda5/0x1940 mm/slub.c:3858
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3948
 __slab_alloc_node mm/slub.c:4023 [inline]
 slab_alloc_node mm/slub.c:4184 [inline]
 __kmalloc_cache_noprof+0x209/0x3c0 mm/slub.c:4353
 kmalloc_noprof include/linux/slab.h:905 [inline]
 audit_log_d_path+0xe7/0x200 kernel/audit.c:2149
 audit_log_lsm_data+0xacf/0x1fe0 security/lsm_audit.c:231
 dump_common_audit_data security/lsm_audit.c:440 [inline]
 common_lsm_audit+0x238/0x300 security/lsm_audit.c:470
 slow_avc_audit+0x186/0x210 security/selinux/avc.c:779
 avc_audit security/selinux/include/avc.h:127 [inline]
 avc_has_perm+0x18b/0x1c0 security/selinux/avc.c:1198
 selinux_bprm_creds_for_exec+0x4ec/0xc60 security/selinux/hooks.c:2365
 security_bprm_creds_for_exec+0x34/0x70 security/security.c:1261
 bprm_execve fs/exec.c:1858 [inline]
 bprm_execve+0x472/0x1600 fs/exec.c:1838
page last free pid 2927 tgid 2927 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0x66c/0xe70 mm/page_alloc.c:2725
 discard_slab mm/slub.c:2716 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3185
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x4e/0x70 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4147 [inline]
 slab_alloc_node mm/slub.c:4196 [inline]
 __do_kmalloc_node mm/slub.c:4326 [inline]
 __kmalloc_noprof+0x1c4/0x4d0 mm/slub.c:4339
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kmalloc_array_noprof include/linux/slab.h:948 [inline]
 ext4_find_extent+0x844/0xa70 fs/ext4/extents.c:916
 ext4_ext_map_blocks+0x27d/0x5d60 fs/ext4/extents.c:4205
 ext4_map_query_blocks+0x82/0x2d0 fs/ext4/inode.c:472
 ext4_map_blocks+0x2b9/0x1390 fs/ext4/inode.c:670
 ext4_mpage_readpages+0xcae/0x1200 fs/ext4/readpage.c:289
 ext4_readahead+0x102/0x140 fs/ext4/inode.c:3208
 read_pages+0x1a4/0xb70 mm/readahead.c:160
 page_cache_ra_unbounded+0x393/0x700 mm/readahead.c:297
 do_page_cache_ra mm/readahead.c:327 [inline]
 page_cache_ra_order+0x205/0x2c0 mm/readahead.c:532
 page_cache_sync_ra+0x4b4/0x9c0 mm/readahead.c:621

Memory state around the buggy address:
 ffff888119cb0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888119cb0680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888119cb0700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888119cb0780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888119cb0800: 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 ffff888119cb0730 by task v4l_id/3394

CPU: 0 UID: 0 PID: 3394 Comm: v4l_id Not tainted 6.15.0-rc6-syzkaller-00177-g882826f58b2c #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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:408 [inline]
 print_report+0xc3/0x670 mm/kasan/report.c:521
 kasan_report+0xe0/0x110 mm/kasan/report.c:634
 v4l2_fh_init+0x27d/0x2c0 drivers/media/v4l2-core/v4l2-fh.c:25
 v4l2_fh_open+0x83/0xc0 drivers/media/v4l2-core/v4l2-fh.c:63
 em28xx_v4l2_open+0x24e/0x7e0 drivers/media/usb/em28xx/em28xx-video.c:2153
 v4l2_open+0x222/0x490 drivers/media/v4l2-core/v4l2-dev.c:429
 chrdev_open+0x231/0x6a0 fs/char_dev.c:414
 do_dentry_open+0x6d7/0x13a0 fs/open.c:956
 vfs_open+0x82/0x3f0 fs/open.c:1086
 do_open fs/namei.c:3880 [inline]
 path_openat+0x1e5e/0x2d40 fs/namei.c:4039
 do_filp_open+0x20b/0x470 fs/namei.c:4066
 do_sys_openat2+0x11b/0x1d0 fs/open.c:1429
 do_sys_open fs/open.c:1444 [inline]
 __do_sys_openat fs/open.c:1460 [inline]
 __se_sys_openat fs/open.c:1455 [inline]
 __x64_sys_openat+0x174/0x210 fs/open.c:1455
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x260 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9ae5108407
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:00007fff617310e0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007f9ae501a880 RCX: 00007f9ae5108407
RDX: 0000000000000000 RSI: 00007fff61731f26 RDI: ffffffffffffff9c
RBP: 0000000000000002 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007fff61731330 R14: 00007f9ae589e000 R15: 00005600ec2484d8
 </TASK>

Allocated by task 2975:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 poison_kmalloc_redzone mm/kasan/common.c:377 [inline]
 __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:394
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 em28xx_v4l2_init+0x114/0x40c0 drivers/media/usb/em28xx/em28xx-video.c:2532
 em28xx_init_extension+0x137/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117
 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 2975:
 kasan_save_stack+0x33/0x60 mm/kasan/common.c:47
 kasan_save_track+0x14/0x30 mm/kasan/common.c:68
 kasan_save_free_info+0x3b/0x60 mm/kasan/generic.c:576
 poison_slab_object mm/kasan/common.c:247 [inline]
 __kasan_slab_free+0x37/0x50 mm/kasan/common.c:264
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2380 [inline]
 slab_free mm/slub.c:4642 [inline]
 kfree+0x286/0x470 mm/slub.c:4841
 em28xx_free_v4l2 drivers/media/usb/em28xx/em28xx-video.c:2118 [inline]
 kref_put include/linux/kref.h:65 [inline]
 em28xx_v4l2_init+0x22c5/0x40c0 drivers/media/usb/em28xx/em28xx-video.c:2901
 em28xx_init_extension+0x137/0x200 drivers/media/usb/em28xx/em28xx-core.c:1117
 request_module_async+0x61/0x70 drivers/media/usb/em28xx/em28xx-cards.c:3457
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c2/0x780 kernel/kthread.c:464
 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff888119cb0000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 1840 bytes inside of
 freed 8192-byte region [ffff888119cb0000, ffff888119cb2000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x119cb0
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
anon flags: 0x200000000000040(head|node=0|zone=2)
page_type: f5(slab)
raw: 0200000000000040 ffff888100042280 0000000000000000 0000000000000001
raw: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 0200000000000040 ffff888100042280 0000000000000000 0000000000000001
head: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 0200000000000003 ffffea0004672c01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 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 0x52820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 2930, tgid 2930 (sshd-session), ts 27108167435, free_ts 27002668038
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x181/0x1b0 mm/page_alloc.c:1718
 prep_new_page mm/page_alloc.c:1726 [inline]
 get_page_from_freelist+0xfec/0x2d90 mm/page_alloc.c:3688
 __alloc_frozen_pages_noprof+0x25c/0x2160 mm/page_alloc.c:4970
 alloc_pages_mpol+0xe4/0x410 mm/mempolicy.c:2301
 alloc_slab_page mm/slub.c:2450 [inline]
 allocate_slab mm/slub.c:2618 [inline]
 new_slab+0x244/0x340 mm/slub.c:2672
 ___slab_alloc+0xda5/0x1940 mm/slub.c:3858
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3948
 __slab_alloc_node mm/slub.c:4023 [inline]
 slab_alloc_node mm/slub.c:4184 [inline]
 __kmalloc_cache_noprof+0x209/0x3c0 mm/slub.c:4353
 kmalloc_noprof include/linux/slab.h:905 [inline]
 audit_log_d_path+0xe7/0x200 kernel/audit.c:2149
 audit_log_lsm_data+0xacf/0x1fe0 security/lsm_audit.c:231
 dump_common_audit_data security/lsm_audit.c:440 [inline]
 common_lsm_audit+0x238/0x300 security/lsm_audit.c:470
 slow_avc_audit+0x186/0x210 security/selinux/avc.c:779
 avc_audit security/selinux/include/avc.h:127 [inline]
 avc_has_perm+0x18b/0x1c0 security/selinux/avc.c:1198
 selinux_bprm_creds_for_exec+0x4ec/0xc60 security/selinux/hooks.c:2365
 security_bprm_creds_for_exec+0x34/0x70 security/security.c:1261
 bprm_execve fs/exec.c:1858 [inline]
 bprm_execve+0x472/0x1600 fs/exec.c:1838
page last free pid 2927 tgid 2927 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1262 [inline]
 __free_frozen_pages+0x66c/0xe70 mm/page_alloc.c:2725
 discard_slab mm/slub.c:2716 [inline]
 __put_partials+0x16d/0x1c0 mm/slub.c:3185
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4e/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x4e/0x70 mm/kasan/common.c:329
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4147 [inline]
 slab_alloc_node mm/slub.c:4196 [inline]
 __do_kmalloc_node mm/slub.c:4326 [inline]
 __kmalloc_noprof+0x1c4/0x4d0 mm/slub.c:4339
 kmalloc_noprof include/linux/slab.h:909 [inline]
 kmalloc_array_noprof include/linux/slab.h:948 [inline]
 ext4_find_extent+0x844/0xa70 fs/ext4/extents.c:916
 ext4_ext_map_blocks+0x27d/0x5d60 fs/ext4/extents.c:4205
 ext4_map_query_blocks+0x82/0x2d0 fs/ext4/inode.c:472
 ext4_map_blocks+0x2b9/0x1390 fs/ext4/inode.c:670
 ext4_mpage_readpages+0xcae/0x1200 fs/ext4/readpage.c:289
 ext4_readahead+0x102/0x140 fs/ext4/inode.c:3208
 read_pages+0x1a4/0xb70 mm/readahead.c:160
 page_cache_ra_unbounded+0x393/0x700 mm/readahead.c:297
 do_page_cache_ra mm/readahead.c:327 [inline]
 page_cache_ra_order+0x205/0x2c0 mm/readahead.c:532
 page_cache_sync_ra+0x4b4/0x9c0 mm/readahead.c:621

Memory state around the buggy address:
 ffff888119cb0600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888119cb0680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888119cb0700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                     ^
 ffff888119cb0780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888119cb0800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================