KASAN: slab-use-after-free Read in k90_backlight_work

Status: upstream: reported on 2026/08/28 15:14
Subsystems: input usb
Labels: prio:high
[Documentation on labels]
Reported-by: syzbot+abcedffc9201f2bb66c2@syzkaller.appspotmail.com
First crash: 4d19h, last: 2d02h
✨ AI Jobs (1)
ID Workflow Result Correct Bug Created Started Finished Revision
8afba160 assessment-security DenialOfService: ✅ Exploitable: ✅ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ✅ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ KASAN: slab-use-after-free Read in k90_backlight_work 2026/08/26 00:01 2026/08/26 00:01 2026/08/26 00:42 ee98d2fd
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [input?] [usb?] KASAN: slab-use-after-free Read in k90_backlight_work 0 (1) 2026/08/28 15:14

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in k90_backlight_work+0x174/0x1c0 drivers/hid/hid-corsair.c:209
Read of size 1 at addr ffff888026a23b00 by task kworker/1:3/5600

CPU: 1 UID: 0 PID: 5600 Comm: kworker/1:3 Tainted: G             L      syzkaller #0 PREEMPT_{RT,(full)} 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: events k90_backlight_work
Call Trace:
 <TASK>
 dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
 print_address_description+0x55/0x1e0 mm/kasan/report.c:378
 print_report+0x58/0x70 mm/kasan/report.c:482
 kasan_report+0x117/0x150 mm/kasan/report.c:595
 k90_backlight_work+0x174/0x1c0 drivers/hid/hid-corsair.c:209
 process_one_work kernel/workqueue.c:3387 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
 kthread+0x38b/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 11427:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_noprof+0x3d5/0x680 mm/slub.c:5563
 _kmalloc_noprof include/linux/slab.h:991 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 k90_init_backlight drivers/hid/hid-corsair.c:430 [inline]
 corsair_probe+0x627/0xbc0 drivers/hid/hid-corsair.c:589
 __hid_device_probe drivers/hid/hid-core.c:2839 [inline]
 hid_device_probe+0x46a/0x870 drivers/hid/hid-core.c:2878
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x254/0xae0 drivers/base/dd.c:706
 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
 bus_for_each_drv+0x25b/0x2f0 drivers/base/bus.c:500
 __device_attach+0x2c7/0x450 drivers/base/dd.c:1098
 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x12d/0x220 drivers/base/bus.c:620
 device_add+0x7d7/0xb80 drivers/base/core.c:3776
 hid_add_device+0x272/0x3e0 drivers/hid/hid-core.c:3065
 usbhid_probe+0x9dc/0xde0 drivers/hid/usbhid/hid-core.c:1452
 usb_probe_interface+0x788/0xe50 drivers/usb/core/driver.c:399
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x254/0xae0 drivers/base/dd.c:706
 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
 bus_for_each_drv+0x25b/0x2f0 drivers/base/bus.c:500
 __device_attach+0x2c7/0x450 drivers/base/dd.c:1098
 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x12d/0x220 drivers/base/bus.c:620
 device_add+0x7d7/0xb80 drivers/base/core.c:3776
 usb_set_configuration+0x1ad8/0x2180 drivers/usb/core/message.c:2268
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
 usb_probe_device+0x1c3/0x3b0 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x254/0xae0 drivers/base/dd.c:706
 __driver_probe_device+0x1e8/0x360 drivers/base/dd.c:868
 driver_probe_device+0x4f/0x240 drivers/base/dd.c:898
 __device_attach_driver+0x270/0x410 drivers/base/dd.c:1026
 bus_for_each_drv+0x25b/0x2f0 drivers/base/bus.c:500
 __device_attach+0x2c7/0x450 drivers/base/dd.c:1098
 device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x12d/0x220 drivers/base/bus.c:620
 device_add+0x7d7/0xb80 drivers/base/core.c:3776
 usb_new_device+0x99a/0x1680 drivers/usb/core/hub.c:2708
 hub_port_connect drivers/usb/core/hub.c:5580 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5720 [inline]
 port_event drivers/usb/core/hub.c:5884 [inline]
 hub_event+0x28cf/0x4cf0 drivers/usb/core/hub.c:5966
 process_one_work kernel/workqueue.c:3387 [inline]
 process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3470
 worker_thread+0xa47/0xfb0 kernel/workqueue.c:3551
 kthread+0x38b/0x470 kernel/kthread.c:436
 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 11427:
 kasan_save_stack mm/kasan/common.c:57 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2748 [inline]
 slab_free mm/slub.c:6499 [inline]
 kfree+0x1c5/0x6d0 mm/slub.c:6792
 hid_device_remove+0xc8/0x1d0 drivers/hid/hid-core.c:2897

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/27 07:48 upstream 73e3f0710014 a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in k90_backlight_work
2026/08/25 10:35 upstream 66498c75b4f8 614e416a .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in k90_backlight_work
2026/08/25 03:50 upstream 66498c75b4f8 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in k90_backlight_work
2026/08/25 03:46 upstream 66498c75b4f8 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in k90_backlight_work
2026/08/24 21:00 upstream 0a0d1d55dad5 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in k90_backlight_work
2026/08/24 16:39 upstream 0a0d1d55dad5 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in k90_backlight_work
2026/08/24 15:05 upstream 0a0d1d55dad5 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce KASAN: slab-use-after-free Read in k90_backlight_work
2026/08/24 18:22 upstream 0a0d1d55dad5 23caa175 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-386 KASAN: slab-use-after-free Read in k90_backlight_work
2026/08/26 23:35 https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git usb-testing 45c13f3f9e3b a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-usb KASAN: slab-use-after-free Read in k90_backlight_work
* Struck through repros no longer work on HEAD.