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KASAN: slab-use-after-free Read in v4l2_release (2)

Status: moderation: reported on 2025/08/14 04:00
Subsystems: media
[Documentation on labels]
Reported-by: syzbot+f1b20958f93d2d250727@syzkaller.appspotmail.com
First crash: 7d12h, last: 7d12h
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: slab-use-after-free Read in v4l2_release media usb 19 C error inconclusive 1 208d 270d 0/29 auto-obsoleted due to no activity on 2025/07/14 22:25
upstream KASAN: use-after-free Read in v4l2_release (3) usb media 19 C error error 34 1491d 2047d 0/29 auto-obsoleted due to no activity on 2023/04/15 03:26

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in v4l2_release+0x3e2/0x460 drivers/media/v4l2-core/v4l2-dev.c:455
Read of size 8 at addr ffff888033c980c8 by task v4l_id/10790

CPU: 0 UID: 0 PID: 10790 Comm: v4l_id Not tainted 6.16.0-syzkaller-12256-g561c80369df0 #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025
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:378 [inline]
 print_report+0xcd/0x630 mm/kasan/report.c:482
 kasan_report+0xe0/0x110 mm/kasan/report.c:595
 v4l2_release+0x3e2/0x460 drivers/media/v4l2-core/v4l2-dev.c:455
 __fput+0x3ff/0xb70 fs/file_table.c:468
 fput_close_sync+0x118/0x210 fs/file_table.c:573
 __do_sys_close fs/open.c:1587 [inline]
 __se_sys_close fs/open.c:1572 [inline]
 __x64_sys_close+0x8b/0x120 fs/open.c:1572
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb391ea7407
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:00007ffc25558ff0 EFLAGS: 00000202 ORIG_RAX: 0000000000000003
RAX: ffffffffffffffda RBX: 00007fb392569880 RCX: 00007fb391ea7407
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: 00007fb3925696e8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 00007ffc25559220 R14: 00007fb3926d0000 R15: 0000559e5e45b4d8
 </TASK>

Allocated by task 5952:
 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:388 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:405
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 hackrf_probe+0xd0/0x1ce0 drivers/media/usb/hackrf/hackrf.c:1351
 usb_probe_interface+0x303/0xa40 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:581 [inline]
 really_probe+0x241/0xa90 drivers/base/dd.c:659
 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:959
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462
 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031
 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
 device_add+0x1148/0x1aa0 drivers/base/core.c:3689
 usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250
 usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:581 [inline]
 really_probe+0x241/0xa90 drivers/base/dd.c:659
 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:959
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462
 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031
 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
 device_add+0x1148/0x1aa0 drivers/base/core.c:3689
 usb_new_device+0xd07/0x1a60 drivers/usb/core/hub.c:2694
 hub_port_connect drivers/usb/core/hub.c:5566 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
 port_event drivers/usb/core/hub.c:5870 [inline]
 hub_event+0x2f34/0x4fe0 drivers/usb/core/hub.c:5952
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 5952:
 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:243 [inline]
 __kasan_slab_free+0x60/0x70 mm/kasan/common.c:275
 kasan_slab_free include/linux/kasan.h:233 [inline]
 slab_free_hook mm/slub.c:2417 [inline]
 slab_free mm/slub.c:4680 [inline]
 kfree+0x2b4/0x4d0 mm/slub.c:4879
 hackrf_probe+0x4c8/0x1ce0 drivers/media/usb/hackrf/hackrf.c:1523
 usb_probe_interface+0x303/0xa40 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:581 [inline]
 really_probe+0x241/0xa90 drivers/base/dd.c:659
 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:959
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462
 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031
 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
 device_add+0x1148/0x1aa0 drivers/base/core.c:3689
 usb_set_configuration+0x1187/0x1e20 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0xb1/0x110 drivers/usb/core/generic.c:250
 usb_probe_device+0xec/0x3e0 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:581 [inline]
 really_probe+0x241/0xa90 drivers/base/dd.c:659
 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:959
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462
 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031
 bus_probe_device+0x17f/0x1c0 drivers/base/bus.c:537
 device_add+0x1148/0x1aa0 drivers/base/core.c:3689
 usb_new_device+0xd07/0x1a60 drivers/usb/core/hub.c:2694
 hub_port_connect drivers/usb/core/hub.c:5566 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
 port_event drivers/usb/core/hub.c:5870 [inline]
 hub_event+0x2f34/0x4fe0 drivers/usb/core/hub.c:5952
 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3236
 process_scheduled_works kernel/workqueue.c:3319 [inline]
 worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400
 kthread+0x3c5/0x780 kernel/kthread.c:463
 ret_from_fork+0x5d4/0x6f0 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff888033c98000
 which belongs to the cache kmalloc-8k of size 8192
The buggy address is located 200 bytes inside of
 freed 8192-byte region [ffff888033c98000, ffff888033c9a000)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x33c98
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000040 ffff88801b842280 dead000000000122 0000000000000000
raw: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 00fff00000000040 ffff88801b842280 dead000000000122 0000000000000000
head: 0000000000000000 0000000080020002 00000000f5000000 0000000000000000
head: 00fff00000000003 ffffea0000cf2601 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5952, tgid 5952 (kworker/0:6), ts 465342065537, free_ts 464097049724
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x1c0/0x230 mm/page_alloc.c:1851
 prep_new_page mm/page_alloc.c:1859 [inline]
 get_page_from_freelist+0x132b/0x38e0 mm/page_alloc.c:3858
 __alloc_frozen_pages_noprof+0x261/0x23f0 mm/page_alloc.c:5148
 alloc_pages_mpol+0x1fb/0x550 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:2487 [inline]
 allocate_slab mm/slub.c:2655 [inline]
 new_slab+0x247/0x330 mm/slub.c:2709
 ___slab_alloc+0xcf2/0x1740 mm/slub.c:3891
 __slab_alloc.constprop.0+0x56/0xb0 mm/slub.c:3981
 __slab_alloc_node mm/slub.c:4056 [inline]
 slab_alloc_node mm/slub.c:4217 [inline]
 __kmalloc_cache_noprof+0xfb/0x3e0 mm/slub.c:4391
 kmalloc_noprof include/linux/slab.h:905 [inline]
 kzalloc_noprof include/linux/slab.h:1039 [inline]
 hackrf_probe+0xd0/0x1ce0 drivers/media/usb/hackrf/hackrf.c:1351
 usb_probe_interface+0x303/0xa40 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:581 [inline]
 really_probe+0x241/0xa90 drivers/base/dd.c:659
 __driver_probe_device+0x1de/0x440 drivers/base/dd.c:801
 driver_probe_device+0x4c/0x1b0 drivers/base/dd.c:831
 __device_attach_driver+0x1df/0x310 drivers/base/dd.c:959
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:462
 __device_attach+0x1e4/0x4b0 drivers/base/dd.c:1031
page last free pid 10752 tgid 10752 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1395 [inline]
 __free_frozen_pages+0x7d5/0x10f0 mm/page_alloc.c:2895
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x4d/0x120 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x195/0x1e0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:340
 kasan_slab_alloc include/linux/kasan.h:250 [inline]
 slab_post_alloc_hook mm/slub.c:4180 [inline]
 slab_alloc_node mm/slub.c:4229 [inline]
 kmem_cache_alloc_noprof+0x1cb/0x3b0 mm/slub.c:4236
 vm_area_dup+0x27/0x8d0 mm/vma_init.c:122
 __split_vma+0x18e/0x1070 mm/vma.c:515
 split_vma mm/vma.c:598 [inline]
 vma_modify+0x16dc/0x2030 mm/vma.c:1623
 vma_modify_flags+0x212/0x2d0 mm/vma.c:1649
 mprotect_fixup+0x1df/0xb40 mm/mprotect.c:819
 do_mprotect_pkey+0x9ca/0xd50 mm/mprotect.c:993
 __do_sys_mprotect mm/mprotect.c:1014 [inline]
 __se_sys_mprotect mm/mprotect.c:1011 [inline]
 __x64_sys_mprotect+0x78/0xc0 mm/mprotect.c:1011
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xcd/0x4c0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff888033c97f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888033c98000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888033c98080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                              ^
 ffff888033c98100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888033c98180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/08/10 03:57 upstream 561c80369df0 32a0e5ed .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-selinux-root KASAN: slab-use-after-free Read in v4l2_release
* Struck through repros no longer work on HEAD.