KASAN: use-after-free Read in steam_input_open

Status: upstream: reported C repro on 2025/03/06 15:18
Bug presence: origin:lts-only
[Documentation on labels]
Reported-by: syzbot+541ce19a7f6f4e686cbc@syzkaller.appspotmail.com
First crash: 517d, last: 83d
Fix commit to backport (bisect log) :
tree: upstream
commit 691ead124a0c35e56633dbb73e43711ff3db23ef
Author: Vicki Pfau <vi@endrift.com>
Date: Wed Dec 20 03:38:33 2023 +0000

  HID: hid-steam: Clean up locking

  
▶ ▼ Bug presence (2)
Date Name Commit Repro Result
2025/03/23 linux-6.1.y (ToT) 344a09659766 C [report] KASAN: use-after-free Read in steam_input_open
2025/03/23 upstream (ToT) 586de92313fc C Didn't crash
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
linux-5.15 KASAN: use-after-free Read in steam_input_open origin:lts-only 19 syz, C done 20 20d 518d 0/3 upstream: reported C repro on 2025/03/06 06:53
android-54 KASAN: use-after-free Write in steam_input_open 22 syz, C 29 456d 527d 0/2 upstream: reported C repro on 2025/02/24 11:20
upstream KASAN: slab-use-after-free Read in steam_input_open input usb 19 syz, C done 5 516d 529d 28/29 fixed on 2025/06/10 16:19
android-5-15 KASAN: use-after-free Write in steam_input_open origin:lts 22 syz, C 106 13d 697d 0/2 upstream: reported C repro on 2024/09/08 02:35
android-6-1 KASAN: use-after-free Write in steam_input_open origin:lts 22 syz, C 103 19d 680d 0/2 upstream: reported C repro on 2024/09/25 04:26
android-5-10 KASAN: use-after-free Write in steam_input_open 22 syz, C inconclusive 240 82d 702d 0/2 upstream: reported C repro on 2024/09/03 09:12
▶ ▼ Fix bisection attempts (1)
Created Duration User Patch Repo Result
2025/03/27 08:40 5h29m fix candidate upstream OK (1) job log

Sample crash report:
==================================================================
BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:582 [inline]
BUG: KASAN: use-after-free in __mutex_lock+0xf4/0xaf0 kernel/locking/mutex.c:747
Read of size 8 at addr ffff888075b3f4e8 by task udevd/4496

CPU: 1 PID: 4496 Comm: udevd Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:316 [inline]
 print_report+0xa8/0x210 mm/kasan/report.c:420
 kasan_report+0x10b/0x140 mm/kasan/report.c:524
 __mutex_lock_common kernel/locking/mutex.c:582 [inline]
 __mutex_lock+0xf4/0xaf0 kernel/locking/mutex.c:747
 steam_input_open+0x93/0x170 drivers/hid/hid-steam.c:297
 input_open_device+0x16c/0x2e0 drivers/input/input.c:650
 evdev_open_device drivers/input/evdev.c:400 [inline]
 evdev_open+0x4b0/0x5b0 drivers/input/evdev.c:487
 chrdev_open+0x5c5/0x6a0 fs/char_dev.c:414
 do_dentry_open+0x7e9/0x10d0 fs/open.c:882
 do_open fs/namei.c:3634 [inline]
 path_openat+0x2635/0x2ee0 fs/namei.c:3791
 do_filp_open+0x1f1/0x430 fs/namei.c:3818
 do_sys_openat2+0x150/0x4b0 fs/open.c:1320
 do_sys_open fs/open.c:1336 [inline]
 __do_sys_openat fs/open.c:1352 [inline]
 __se_sys_openat fs/open.c:1347 [inline]
 __x64_sys_openat+0x135/0x160 fs/open.c:1347
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fc30eaa7407
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:00007fff28a980a0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 00007fc30f1d5880 RCX: 00007fc30eaa7407
RDX: 0000000000080000 RSI: 000055885c1051d0 RDI: ffffffffffffff9c
RBP: 000055885c15c2a0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000202 R12: 00005588247d60c8
R13: 00005588247d60ce R14: 00007fff28a986a0 R15: 00005588247dcbcc
 </TASK>

Allocated by task 4458:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 ____kasan_kmalloc mm/kasan/common.c:375 [inline]
 __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 __do_kmalloc_node mm/slab_common.c:936 [inline]
 __kmalloc_node_track_caller+0xae/0x230 mm/slab_common.c:956
 alloc_dr drivers/base/devres.c:116 [inline]
 devm_kmalloc+0x77/0x280 drivers/base/devres.c:833
 devm_kzalloc include/linux/device.h:210 [inline]
 steam_probe+0x11b/0xb80 drivers/hid/hid-steam.c:741
 hid_device_probe+0x25c/0x350 drivers/hid/hid-core.c:2646
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2aa/0xc70 drivers/base/dd.c:639
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815
 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a8/0x480 drivers/base/dd.c:1015
 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
 device_add+0xa00/0xfb0 drivers/base/core.c:3697
 hid_add_device+0x389/0x530 drivers/hid/hid-core.c:2798
 usbhid_probe+0xc09/0xfe0 drivers/hid/usbhid/hid-core.c:1442
 usb_probe_interface+0x5c5/0xb20 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2aa/0xc70 drivers/base/dd.c:639
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815
 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a8/0x480 drivers/base/dd.c:1015
 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
 device_add+0xa00/0xfb0 drivers/base/core.c:3697
 usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2223
 usb_generic_driver_probe+0x89/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x139/0x270 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x2aa/0xc70 drivers/base/dd.c:639
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:785
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:815
 __device_attach_driver+0x2c6/0x510 drivers/base/dd.c:943
 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429
 __device_attach+0x2a8/0x480 drivers/base/dd.c:1015
 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489
 device_add+0xa00/0xfb0 drivers/base/core.c:3697
 usb_new_device+0xd66/0x1650 drivers/usb/core/hub.c:2659
 hub_port_connect drivers/usb/core/hub.c:5517 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5657 [inline]
 port_event drivers/usb/core/hub.c:5817 [inline]
 hub_event+0x2dcf/0x5560 drivers/usb/core/hub.c:5899
 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
 worker_thread+0xaa2/0x1270 kernel/workqueue.c:2439
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 4458:
 kasan_save_stack mm/kasan/common.c:46 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:53
 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3700
 release_nodes drivers/base/devres.c:503 [inline]
 devres_release_all+0x1a9/0x230 drivers/base/devres.c:532
 device_unbind_cleanup drivers/base/dd.c:530 [inline]
 __device_release_driver drivers/base/dd.c:1265 [inline]
 device_release_driver_internal+0x5a0/0x850 drivers/base/dd.c:1286
 bus_remove_device+0x2e2/0x400 drivers/base/bus.c:531
 device_del+0x6af/0xaf0 drivers/base/core.c:3885
 hid_remove_device drivers/hid/hid-core.c:2847 [inline]
 hid_destroy_device+0x66/0x100 drivers/hid/hid-core.c:2866
 usbhid_disconnect+0x9b/0xc0 drivers/hid/usbhid/hid-core.c:1469
 usb_unbind_interface+0x1ee/0x860 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:550 [inline]
 __device_release_driver drivers/base/dd.c:1260 [inline]
 device_release_driver_internal+0x522/0x850 drivers/base/dd.c:1286
 bus_remove_device+0x2e2/0x400 drivers/base/bus.c:531
 device_del+0x6af/0xaf0 drivers/base/core.c:3885
 usb_disable_device+0x3e2/0x890 drivers/usb/core/message.c:1472
 usb_disconnect+0x348/0x8a0 drivers/usb/core/hub.c:2314
 hub_port_connect drivers/usb/core/hub.c:5361 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5657 [inline]
 port_event drivers/usb/core/hub.c:5817 [inline]
 hub_event+0x1e50/0x5560 drivers/usb/core/hub.c:5899
 process_one_work+0x8a2/0x1160 kernel/workqueue.c:2292
 process_scheduled_works kernel/workqueue.c:2355 [inline]
 worker_thread+0xd27/0x1270 kernel/workqueue.c:2441
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

The buggy address belongs to the object at ffff888075b3f400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 232 bytes inside of
 512-byte region [ffff888075b3f400, ffff888075b3f600)

The buggy address belongs to the physical page:
page:ffffea0001d6cf00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x75b3c
head:ffffea0001d6cf00 order:2 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888017441c80
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 4382, tgid 4382 (syz-executor), ts 92201048072, free_ts 92161654079
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559
 prep_new_page mm/page_alloc.c:2566 [inline]
 get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357
 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5657
 alloc_slab_page+0x5d/0x160 mm/slub.c:1799
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x87/0x2c0 mm/slub.c:1997
 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154
 __slab_alloc mm/slub.c:3240 [inline]
 slab_alloc_node mm/slub.c:3325 [inline]
 __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398
 __do_kmalloc_node mm/slab_common.c:935 [inline]
 __kmalloc_node_track_caller+0x9e/0x230 mm/slab_common.c:956
 kmalloc_reserve net/core/skbuff.c:446 [inline]
 __alloc_skb+0x22a/0x7e0 net/core/skbuff.c:515
 alloc_skb include/linux/skbuff.h:1303 [inline]
 alloc_uevent_skb+0x7d/0x230 lib/kobject_uevent.c:290
 uevent_net_broadcast_tagged lib/kobject_uevent.c:351 [inline]
 kobject_uevent_net_broadcast+0x17e/0x530 lib/kobject_uevent.c:412
 kobject_uevent_env+0x54c/0x8a0 lib/kobject_uevent.c:608
 rx_queue_add_kobject net/core/net-sysfs.c:1072 [inline]
 net_rx_queue_update_kobjects+0x23f/0x4a0 net/core/net-sysfs.c:1112
 register_queue_kobjects net/core/net-sysfs.c:1772 [inline]
 netdev_register_kobject+0x231/0x320 net/core/net-sysfs.c:2017
 register_netdevice+0x12dc/0x1b10 net/core/dev.c:10243
 register_netdev+0x37/0x50 net/core/dev.c:10371
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1486 [inline]
 free_pcp_prepare mm/page_alloc.c:1536 [inline]
 free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413
 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:306
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737
 slab_alloc_node mm/slub.c:3359 [inline]
 __kmem_cache_alloc_node+0x140/0x260 mm/slub.c:3398
 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026
 kmalloc include/linux/slab.h:563 [inline]
 rtnl_newlink+0x10c/0x20a0 net/core/rtnetlink.c:3656
 rtnetlink_rcv_msg+0x87c/0xfc0 net/core/rtnetlink.c:6157
 netlink_rcv_skb+0x1fb/0x450 net/netlink/af_netlink.c:2511
 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline]
 netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344
 netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1872
 sock_sendmsg_nosec net/socket.c:718 [inline]
 __sock_sendmsg net/socket.c:730 [inline]
 __sys_sendto+0x497/0x650 net/socket.c:2152
 __do_sys_sendto net/socket.c:2164 [inline]
 __se_sys_sendto net/socket.c:2160 [inline]
 __x64_sys_sendto+0xda/0xf0 net/socket.c:2160
 do_syscall_x64 arch/x86/entry/common.c:46 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76

Memory state around the buggy address:
 ffff888075b3f380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888075b3f400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888075b3f480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff888075b3f500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888075b3f580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/14 18:35 linux-6.1.y ad16b162f21d 6ccb967e .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in steam_input_open
2025/03/07 08:37 linux-6.1.y 3a8358583626 831e3629 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in steam_input_open
2025/03/06 16:17 linux-6.1.y 3a8358583626 831e3629 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in steam_input_open
2025/03/06 15:29 linux-6.1.y 3a8358583626 831e3629 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in steam_input_open
2025/03/06 15:17 linux-6.1.y 3a8358583626 831e3629 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in steam_input_open
2025/03/12 08:04 linux-6.1.y 6ae7ac5c4251 ee70e6db .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in steam_input_open
* Struck through repros no longer work on HEAD.