KASAN: use-after-free Read in roccat_disconnect

Status: upstream: reported C repro on 2026/10/26 05:36
Reported-by: syzbot+9fab75fa4229812edfaa@syzkaller.appspotmail.com
First crash: 12d, last: 19h56m
▶ ▼ Similar bugs (7)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-6.1 KASAN: use-after-free Read in roccat_disconnect 19 syz, C 9 2d06h 6d04h 0/3 upstream: reported C repro on 2026/11/01 22:08
android-5-10 KASAN: use-after-free Read in roccat_disconnect 19 syz, C 10 5d14h 50d 0/2 upstream: reported C repro on 2026/09/18 05:49
android-5-15 KASAN: use-after-free Read in roccat_disconnect 19 syz, C 12 4d05h 57d 0/2 upstream: reported C repro on 2026/09/11 19:13
android-6-1 KASAN: use-after-free Read in roccat_disconnect 19 syz, C 14 4d05h 16d 0/2 upstream: reported C repro on 2026/10/22 14:43
linux-6.6 KASAN: slab-use-after-free Read in roccat_disconnect 19 syz, C 9 6d11h 16d 0/2 upstream: reported C repro on 2026/10/22 21:24
android-6-12 KASAN: slab-use-after-free Read in roccat_disconnect origin:lts 19 syz, C 39 3d05h 55d 0/1 premoderation: reported C repro on 2026/09/13 11:34
upstream KASAN: slab-use-after-free Read in roccat_disconnect prio:high input usb 19 syz, C error error 20 46d 66d 2/29 upstream: reported C repro on 2026/09/02 18:57

Sample crash report:
usb 4-1: USB disconnect, device number 5
==================================================================
BUG: KASAN: use-after-free in roccat_disconnect+0x236/0x240 drivers/hid/hid-roccat.c:382
Read of size 4 at addr ffff88807a8d3808 by task kworker/1:2/2239

CPU: 1 PID: 2239 Comm: kworker/1:2 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/15/2026
Workqueue: usb_hub_wq hub_event
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 roccat_disconnect+0x236/0x240 drivers/hid/hid-roccat.c:382
 savu_remove_specials drivers/hid/hid-roccat-savu.c:107 [inline]
 savu_remove+0xe5/0x160 drivers/hid/hid-roccat-savu.c:147
 hid_device_remove+0xba/0x1b0 drivers/hid/hid-core.c:2435
 __device_release_driver drivers/base/dd.c:1247 [inline]
 device_release_driver_internal+0x44c/0x710 drivers/base/dd.c:1282
 bus_remove_device+0x2dd/0x400 drivers/base/bus.c:531
 device_del+0x63f/0xa80 drivers/base/core.c:3615
 hid_remove_device drivers/hid/hid-core.c:2611 [inline]
 hid_destroy_device+0x66/0x100 drivers/hid/hid-core.c:2630
 usbhid_disconnect+0x9b/0xc0 drivers/hid/usbhid/hid-core.c:1470
 usb_unbind_interface+0x203/0x870 drivers/usb/core/driver.c:458
 __device_release_driver drivers/base/dd.c:1249 [inline]
 device_release_driver_internal+0x487/0x710 drivers/base/dd.c:1282
 bus_remove_device+0x2dd/0x400 drivers/base/bus.c:531
 device_del+0x63f/0xa80 drivers/base/core.c:3615
 usb_disable_device+0x3e7/0x8a0 drivers/usb/core/message.c:1478
 usb_disconnect+0x33c/0x8a0 drivers/usb/core/hub.c:2297
 hub_port_connect drivers/usb/core/hub.c:5351 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5647 [inline]
 port_event drivers/usb/core/hub.c:5809 [inline]
 hub_event+0x1d64/0x5260 drivers/usb/core/hub.c:5891
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Allocated by task 4237:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:46 [inline]
 set_alloc_info mm/kasan/common.c:434 [inline]
 ____kasan_kmalloc mm/kasan/common.c:513 [inline]
 __kasan_kmalloc+0xaf/0xe0 mm/kasan/common.c:522
 kmalloc include/linux/slab.h:607 [inline]
 kzalloc include/linux/slab.h:738 [inline]
 roccat_connect+0x59/0x490 drivers/hid/hid-roccat.c:315
 savu_init_specials drivers/hid/hid-roccat-savu.c:81 [inline]
 savu_probe+0x1af/0x350 drivers/hid/hid-roccat-savu.c:131
 __hid_device_probe drivers/hid/hid-core.c:2377 [inline]
 hid_device_probe+0x2cb/0x590 drivers/hid/hid-core.c:2416
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x276/0xc70 drivers/base/dd.c:595
 __driver_probe_device+0x1f5/0x390 drivers/base/dd.c:775
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:805
 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:927
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a7/0x480 drivers/base/dd.c:999
 bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489
 device_add+0xbcf/0x1050 drivers/base/core.c:3427
 hid_add_device+0x361/0x500 drivers/hid/hid-core.c:2562
 usbhid_probe+0xbc5/0xf50 drivers/hid/usbhid/hid-core.c:1443
 usb_probe_interface+0x5be/0xae0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x276/0xc70 drivers/base/dd.c:595
 __driver_probe_device+0x1f5/0x390 drivers/base/dd.c:775
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:805
 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:927
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a7/0x480 drivers/base/dd.c:999
 bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489
 device_add+0xbcf/0x1050 drivers/base/core.c:3427
 usb_set_configuration+0x1ad8/0x2140 drivers/usb/core/message.c:2229
 usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x126/0x250 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x276/0xc70 drivers/base/dd.c:595
 __driver_probe_device+0x1f5/0x390 drivers/base/dd.c:775
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:805
 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:927
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a7/0x480 drivers/base/dd.c:999
 bus_probe_device+0xba/0x1d0 drivers/base/bus.c:489
 device_add+0xbcf/0x1050 drivers/base/core.c:3427
 usb_new_device+0x9f6/0x15d0 drivers/usb/core/hub.c:2642
 hub_port_connect drivers/usb/core/hub.c:5507 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5647 [inline]
 port_event drivers/usb/core/hub.c:5809 [inline]
 hub_event+0x2b8d/0x5260 drivers/usb/core/hub.c:5891
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Freed by task 4483:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:46
 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360
 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366
 kasan_slab_free include/linux/kasan.h:230 [inline]
 slab_free_hook mm/slub.c:1710 [inline]
 slab_free_freelist_hook+0xec/0x170 mm/slub.c:1736
 slab_free mm/slub.c:3504 [inline]
 kfree+0xef/0x2a0 mm/slub.c:4564
 roccat_release+0x2a6/0x370 drivers/hid/hid-roccat.c:238
 __fput+0x212/0x8c0 fs/file_table.c:311
 task_work_run+0x125/0x1a0 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:184
 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:217
 __syscall_exit_to_user_mode_work kernel/entry/common.c:299 [inline]
 syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:310
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88807a8d3800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 8 bytes inside of
 1024-byte region [ffff88807a8d3800, ffff88807a8d3c00)
The buggy address belongs to the page:
page:ffffea0001ea3400 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7a8d0
head:ffffea0001ea3400 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888017841dc0
raw: 0000000000000000 0000000000100010 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 0x152a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 9, ts 94343876617, free_ts 94305897517
 prep_new_page mm/page_alloc.c:2426 [inline]
 get_page_from_freelist+0x24f6/0x2670 mm/page_alloc.c:4192
 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501
 alloc_slab_page mm/slub.c:1780 [inline]
 allocate_slab mm/slub.c:1917 [inline]
 new_slab+0xc0/0x4b0 mm/slub.c:1980
 ___slab_alloc+0x807/0xdd0 mm/slub.c:3013
 __slab_alloc mm/slub.c:3100 [inline]
 slab_alloc_node mm/slub.c:3191 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 __kmalloc+0x11d/0x340 mm/slub.c:4408
 kmalloc include/linux/slab.h:612 [inline]
 kzalloc include/linux/slab.h:738 [inline]
 ieee802_11_parse_elems_crc+0xb3/0x1090 net/mac80211/util.c:1478
 ieee802_11_parse_elems net/mac80211/ieee80211_i.h:2243 [inline]
 ieee80211_rx_mgmt_probe_beacon net/mac80211/ibss.c:1609 [inline]
 ieee80211_ibss_rx_queued_mgmt+0x36b/0x2b50 net/mac80211/ibss.c:1643
 ieee80211_iface_process_skb net/mac80211/iface.c:1467 [inline]
 ieee80211_iface_work+0x714/0xc50 net/mac80211/iface.c:1521
 cfg80211_wiphy_work+0x224/0x260 net/wireless/core.c:433
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1340 [inline]
 free_pcp_prepare mm/page_alloc.c:1391 [inline]
 free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317
 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396
 free_slab mm/slub.c:2020 [inline]
 discard_slab mm/slub.c:2026 [inline]
 __unfreeze_partials+0x188/0x1e0 mm/slub.c:2512
 put_cpu_partial+0x12d/0x190 mm/slub.c:2592
 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xc0 mm/kasan/common.c:444
 kasan_slab_alloc include/linux/kasan.h:254 [inline]
 slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519
 slab_alloc_node mm/slub.c:3225 [inline]
 slab_alloc mm/slub.c:3233 [inline]
 kmem_cache_alloc_trace+0x165/0x290 mm/slub.c:3250
 kmalloc include/linux/slab.h:607 [inline]
 kzalloc include/linux/slab.h:738 [inline]
 mca_alloc net/ipv6/mcast.c:887 [inline]
 __ipv6_dev_mc_inc+0x47b/0xb20 net/ipv6/mcast.c:942
 addrconf_join_solict net/ipv6/addrconf.c:2212 [inline]
 addrconf_dad_begin net/ipv6/addrconf.c:4034 [inline]
 addrconf_dad_work+0x3bd/0x1530 net/ipv6/addrconf.c:4161
 process_one_work+0x867/0xff0 kernel/workqueue.c:2310
 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457
 kthread+0x42e/0x520 kernel/kthread.c:334
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Memory state around the buggy address:
 ffff88807a8d3700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88807a8d3780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88807a8d3800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff88807a8d3880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88807a8d3900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (9):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/11/07 06:22 linux-5.15.y 29c6cdaac04a 5cecaf1f .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in roccat_disconnect
2026/11/05 03:07 linux-5.15.y 700e62ea909a 73438ed0 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in roccat_disconnect
2026/11/01 23:45 linux-5.15.y 700e62ea909a 25a0ae84 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in roccat_disconnect
2026/10/30 05:22 linux-5.15.y 792fbe1537d8 b498adee .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in roccat_disconnect
2026/10/28 04:57 linux-5.15.y 792fbe1537d8 96923c60 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in roccat_disconnect
2026/10/26 09:56 linux-5.15.y 792fbe1537d8 1d9ca40b .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in roccat_disconnect
2026/10/26 08:00 linux-5.15.y 792fbe1537d8 1d9ca40b .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in roccat_disconnect
2026/10/28 16:39 linux-5.15.y 792fbe1537d8 858db2ec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in roccat_disconnect
2026/10/26 05:36 linux-5.15.y 792fbe1537d8 1d9ca40b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: use-after-free Read in roccat_disconnect
* Struck through repros no longer work on HEAD.