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KASAN: use-after-free Read in move_linked_works (3)

Status: premoderation: reported on 2025/11/14 05:59
Reported-by: syzbot+0f16b1f66f89b905b386@syzkaller.appspotmail.com
First crash: 107d, last: 89d
▶ ▼ Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 KASAN: use-after-free Read in move_linked_works (2) origin:downstream 19 C error 7 237d 777d 0/2 auto-obsoleted due to no activity on 2026/02/23 20:13
android-5-15 KASAN: use-after-free Read in move_linked_works 19 1 1105d 1105d 0/2 auto-obsoleted due to no activity on 2023/05/21 05:23
android-6-1 KASAN: use-after-free Read in move_linked_works 19 2 610d 677d 0/2 auto-obsoleted due to no activity on 2024/09/27 08:05
android-6-1 KASAN: use-after-free Read in move_linked_works (2) 19 1 248d 248d 0/2 auto-obsoleted due to no activity on 2025/09/24 09:48

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in __list_del_entry_valid+0xa6/0x130 lib/list_debug.c:62
Read of size 8 at addr ffff88811a684cf0 by task kworker/0:10/2164

CPU: 0 PID: 2164 Comm: kworker/0:10 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Workqueue:  0x0 (events)
Call Trace:
 <TASK>
 __dump_stack+0x21/0x24 lib/dump_stack.c:88
 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106
 print_address_description+0x71/0x200 mm/kasan/report.c:316
 print_report+0x4a/0x60 mm/kasan/report.c:420
 kasan_report+0x122/0x150 mm/kasan/report.c:524
 __asan_report_load8_noabort+0x14/0x20 mm/kasan/report_generic.c:351
 __list_del_entry_valid+0xa6/0x130 lib/list_debug.c:62
 __list_del_entry include/linux/list.h:134 [inline]
 list_move_tail include/linux/list.h:229 [inline]
 move_linked_works+0x6a/0x230 kernel/workqueue.c:1099
 process_one_work+0x2fc/0xc40 kernel/workqueue.c:2227
 worker_thread+0xa29/0x11f0 kernel/workqueue.c:2449
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Allocated by task 1322:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505
 ____kasan_kmalloc mm/kasan/common.c:379 [inline]
 __kasan_kmalloc+0x95/0xb0 mm/kasan/common.c:388
 kasan_kmalloc include/linux/kasan.h:212 [inline]
 __do_kmalloc_node mm/slab_common.c:938 [inline]
 __kmalloc_node+0xb2/0x1e0 mm/slab_common.c:945
 kmalloc_node include/linux/slab.h:589 [inline]
 kvmalloc_node+0x294/0x480 mm/util.c:592
 kvmalloc include/linux/slab.h:716 [inline]
 kvzalloc include/linux/slab.h:724 [inline]
 alloc_netdev_mqs+0x8d/0xf90 net/core/dev.c:10708
 alloc_etherdev_mqs+0x37/0x40 net/ethernet/eth.c:384
 usbnet_probe+0x20c/0x2780 drivers/net/usb/usbnet.c:1723
 usb_probe_interface+0x610/0xaf0 drivers/usb/core/driver.c:397
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2cb/0x960 drivers/base/dd.c:639
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:808
 driver_probe_device+0x54/0x3e0 drivers/base/dd.c:838
 __device_attach_driver+0x2e9/0x4a0 drivers/base/dd.c:966
 bus_for_each_drv+0x183/0x210 drivers/base/bus.c:429
 __device_attach+0x2a2/0x400 drivers/base/dd.c:1038
 device_initial_probe+0x1a/0x20 drivers/base/dd.c:1087
 bus_probe_device+0xc0/0x1f0 drivers/base/bus.c:489
 device_add+0xb4d/0xef0 drivers/base/core.c:3698
 usb_set_configuration+0x19c2/0x1f10 drivers/usb/core/message.c:2165
 usb_generic_driver_probe+0x91/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x159/0x270 drivers/usb/core/driver.c:294
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2cb/0x960 drivers/base/dd.c:639
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:808
 driver_probe_device+0x54/0x3e0 drivers/base/dd.c:838
 __device_attach_driver+0x2e9/0x4a0 drivers/base/dd.c:966
 bus_for_each_drv+0x183/0x210 drivers/base/bus.c:429
 __device_attach+0x2a2/0x400 drivers/base/dd.c:1038
 device_initial_probe+0x1a/0x20 drivers/base/dd.c:1087
 bus_probe_device+0xc0/0x1f0 drivers/base/bus.c:489
 device_add+0xb4d/0xef0 drivers/base/core.c:3698
 usb_new_device+0xa70/0x1520 drivers/usb/core/hub.c:2684
 hub_port_connect drivers/usb/core/hub.c:5594 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5734 [inline]
 port_event drivers/usb/core/hub.c:5898 [inline]
 hub_event+0x2850/0x4350 drivers/usb/core/hub.c:5980
 process_one_work+0x71f/0xc40 kernel/workqueue.c:2302
 worker_thread+0xa29/0x11f0 kernel/workqueue.c:2449
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 1322:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x31/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:241
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:249
 kasan_slab_free include/linux/kasan.h:178 [inline]
 slab_free_hook mm/slub.c:1750 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776
 slab_free mm/slub.c:3712 [inline]
 __kmem_cache_free+0xb7/0x1b0 mm/slub.c:3728
 kfree+0x6f/0xf0 mm/slab_common.c:990
 kvfree+0x35/0x40 mm/util.c:639
 netdev_freemem+0x3f/0x60 net/core/dev.c:10662
 netdev_release+0x7f/0xb0 net/core/net-sysfs.c:1904
 device_release+0xa4/0x1d0 drivers/base/core.c:-1
 kobject_cleanup lib/kobject.c:681 [inline]
 kobject_release lib/kobject.c:712 [inline]
 kref_put include/linux/kref.h:65 [inline]
 kobject_put+0x19d/0x280 lib/kobject.c:729
 put_device+0x1f/0x30 drivers/base/core.c:3806
 free_netdev+0x392/0x490 net/core/dev.c:10855
 usbnet_disconnect+0x25a/0x3b0 drivers/net/usb/usbnet.c:1662
 usb_unbind_interface+0x223/0x8d0 drivers/usb/core/driver.c:459
 device_remove drivers/base/dd.c:550 [inline]
 __device_release_driver drivers/base/dd.c:1283 [inline]
 device_release_driver_internal+0x508/0x820 drivers/base/dd.c:1309
 device_release_driver+0x19/0x20 drivers/base/dd.c:1332
 bus_remove_device+0x2ee/0x350 drivers/base/bus.c:531
 device_del+0x6a4/0xeb0 drivers/base/core.c:3886
 usb_disable_device+0x3a8/0x750 drivers/usb/core/message.c:1414
 usb_disconnect+0x31e/0x860 drivers/usb/core/hub.c:2339
 hub_port_connect drivers/usb/core/hub.c:5433 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5734 [inline]
 port_event drivers/usb/core/hub.c:5898 [inline]
 hub_event+0x1a78/0x4350 drivers/usb/core/hub.c:5980
 process_one_work+0x71f/0xc40 kernel/workqueue.c:2302
 process_scheduled_works kernel/workqueue.c:2365 [inline]
 worker_thread+0xd2e/0x11f0 kernel/workqueue.c:2451
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Last potentially related work creation:
 kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb6/0xc0 mm/kasan/generic.c:486
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:496
 insert_work+0x51/0x300 kernel/workqueue.c:1368
 __queue_work+0x9b1/0xd30 kernel/workqueue.c:1527
 queue_work_on+0xd2/0x140 kernel/workqueue.c:1555
 queue_work include/linux/workqueue.h:510 [inline]
 schedule_work include/linux/workqueue.h:571 [inline]
 usbnet_defer_kevent drivers/net/usb/usbnet.c:479 [inline]
 usbnet_link_change+0x189/0x1b0 drivers/net/usb/usbnet.c:-1
 usbnet_probe+0x1d55/0x2780 drivers/net/usb/usbnet.c:1868
 usb_probe_interface+0x610/0xaf0 drivers/usb/core/driver.c:397
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2cb/0x960 drivers/base/dd.c:639
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:808
 driver_probe_device+0x54/0x3e0 drivers/base/dd.c:838
 __device_attach_driver+0x2e9/0x4a0 drivers/base/dd.c:966
 bus_for_each_drv+0x183/0x210 drivers/base/bus.c:429
 __device_attach+0x2a2/0x400 drivers/base/dd.c:1038
 device_initial_probe+0x1a/0x20 drivers/base/dd.c:1087
 bus_probe_device+0xc0/0x1f0 drivers/base/bus.c:489
 device_add+0xb4d/0xef0 drivers/base/core.c:3698
 usb_set_configuration+0x19c2/0x1f10 drivers/usb/core/message.c:2165
 usb_generic_driver_probe+0x91/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x159/0x270 drivers/usb/core/driver.c:294
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2cb/0x960 drivers/base/dd.c:639
 __driver_probe_device+0x198/0x280 drivers/base/dd.c:808
 driver_probe_device+0x54/0x3e0 drivers/base/dd.c:838
 __device_attach_driver+0x2e9/0x4a0 drivers/base/dd.c:966
 bus_for_each_drv+0x183/0x210 drivers/base/bus.c:429
 __device_attach+0x2a2/0x400 drivers/base/dd.c:1038
 device_initial_probe+0x1a/0x20 drivers/base/dd.c:1087
 bus_probe_device+0xc0/0x1f0 drivers/base/bus.c:489
 device_add+0xb4d/0xef0 drivers/base/core.c:3698
 usb_new_device+0xa70/0x1520 drivers/usb/core/hub.c:2684
 hub_port_connect drivers/usb/core/hub.c:5594 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5734 [inline]
 port_event drivers/usb/core/hub.c:5898 [inline]
 hub_event+0x2850/0x4350 drivers/usb/core/hub.c:5980
 process_one_work+0x71f/0xc40 kernel/workqueue.c:2302
 worker_thread+0xa29/0x11f0 kernel/workqueue.c:2449
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff88811a684000
 which belongs to the cache kmalloc-4k of size 4096
The buggy address is located 3312 bytes inside of
 4096-byte region [ffff88811a684000, ffff88811a685000)

The buggy address belongs to the physical page:
page:ffffea000469a000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11a680
head:ffffea000469a000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 dead000000000122 ffff888100043380
raw: 0000000000000000 0000000000040004 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 1322, tgid 1322 (kworker/0:8), ts 215764193102, free_ts 153081832537
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2643
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2650
 get_page_from_freelist+0x2c7b/0x2cf0 mm/page_alloc.c:4554
 __alloc_pages+0x1c3/0x450 mm/page_alloc.c:5868
 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1
 allocate_slab mm/slub.c:1967 [inline]
 new_slab+0x98/0x3d0 mm/slub.c:2020
 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177
 __slab_alloc+0x5e/0xa0 mm/slub.c:3263
 slab_alloc_node mm/slub.c:3348 [inline]
 __kmem_cache_alloc_node+0x203/0x2c0 mm/slub.c:3423
 kmalloc_trace+0x29/0xb0 mm/slab_common.c:1028
 kmalloc include/linux/slab.h:563 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 kobject_uevent_env+0x287/0x730 lib/kobject_uevent.c:539
 kobject_uevent+0x1d/0x30 lib/kobject_uevent.c:657
 device_add+0xa5c/0xef0 drivers/base/core.c:3679
 usb_set_configuration+0x19c2/0x1f10 drivers/usb/core/message.c:2165
 usb_generic_driver_probe+0x91/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x159/0x270 drivers/usb/core/driver.c:294
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1551 [inline]
 free_pcp_prepare mm/page_alloc.c:1625 [inline]
 free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3589
 free_unref_page+0x8f/0x530 mm/page_alloc.c:3687
 free_the_page mm/page_alloc.c:836 [inline]
 __free_pages+0x67/0x100 mm/page_alloc.c:5957
 __free_slab+0xca/0x1a0 mm/slub.c:2044
 free_slab mm/slub.c:2059 [inline]
 discard_slab mm/slub.c:2065 [inline]
 __unfreeze_partials+0x160/0x190 mm/slub.c:2614
 put_cpu_partial+0xa9/0x100 mm/slub.c:2690
 __slab_free+0x1c4/0x280 mm/slub.c:3589
 do_slab_free mm/slub.c:3666 [inline]
 ___cache_free+0xbf/0xd0 mm/slub.c:3722
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0xc6/0x140 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x24/0x80 mm/kasan/common.c:310
 kasan_slab_alloc include/linux/kasan.h:202 [inline]
 slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768
 slab_alloc_node mm/slub.c:3382 [inline]
 slab_alloc mm/slub.c:3392 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3399 [inline]
 kmem_cache_alloc+0x16e/0x330 mm/slub.c:3408
 vm_area_alloc+0x24/0x1a0 kernel/fork.c:496
 __mmap_region mm/mmap.c:2862 [inline]
 mmap_region+0xf9f/0x2290 mm/mmap.c:3030
 do_mmap+0x843/0xdc0 mm/mmap.c:1491

Memory state around the buggy address:
 ffff88811a684b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811a684c00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88811a684c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff88811a684d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811a684d80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/12/02 08:14 android14-6.1 5b6cecf56c72 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 KASAN: use-after-free Read in move_linked_works
2025/11/14 05:58 android14-6.1 f090d4b083a9 07e030de .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-6-1 KASAN: use-after-free Read in move_linked_works
* Struck through repros no longer work on HEAD.