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

Status: upstream: reported C repro on 2025/07/02 00:09
Bug presence: origin:upstream
[Documentation on labels]
Reported-by: syzbot+8c9af143864c35b66658@syzkaller.appspotmail.com
First crash: 420d, last: 159d
Fix bisection: failed (error log, bisect log)
  
▶ ▼ Bug presence (1)
Date Name Commit Repro Result
2025/07/05 upstream (ToT) a79a588fc176 C [report] WARNING in usb_free_urb

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in __lock_acquire+0xff/0x7c80 kernel/locking/lockdep.c:5005
Read of size 8 at addr ffff8880604a1098 by task kworker/1:1/27

CPU: 1 PID: 27 Comm: kworker/1:1 Not tainted 6.6.95-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue: events do_submit_urb
Call Trace:
 <TASK>
 dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:364 [inline]
 print_report+0xac/0x230 mm/kasan/report.c:475
 kasan_report+0x117/0x150 mm/kasan/report.c:588
 __lock_acquire+0xff/0x7c80 kernel/locking/lockdep.c:5005
 lock_acquire+0x197/0x410 kernel/locking/lockdep.c:5754
 __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:110 [inline]
 _raw_spin_lock_irqsave+0xa8/0xf0 kernel/locking/spinlock.c:162
 get_entry drivers/media/common/siano/smscoreapi.c:1633 [inline]
 smscore_getbuffer+0xa9/0x440 drivers/media/common/siano/smscoreapi.c:1646
 smsusb_submit_urb drivers/media/usb/siano/smsusb.c:155 [inline]
 do_submit_urb+0x98/0x360 drivers/media/usb/siano/smsusb.c:75
 process_one_work kernel/workqueue.c:2634 [inline]
 process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293
 </TASK>

Allocated by task 5814:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383
 kmalloc include/linux/slab.h:600 [inline]
 kzalloc include/linux/slab.h:721 [inline]
 smscore_register_device+0x63/0x10f0 drivers/media/common/siano/smscoreapi.c:650
 smsusb_init_device drivers/media/usb/siano/smsusb.c:455 [inline]
 smsusb_probe+0x1362/0x1da0 drivers/media/usb/siano/smsusb.c:569
 usb_probe_interface+0x5a4/0xb00 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x25b/0xb40 drivers/base/dd.c:658
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
 __device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958
 bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459
 __device_attach+0x2b5/0x400 drivers/base/dd.c:1030
 bus_probe_device+0x180/0x260 drivers/base/bus.c:534
 device_add+0x85b/0xc20 drivers/base/core.c:3683
 usb_set_configuration+0x1a79/0x20c0 drivers/usb/core/message.c:2207
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x13d/0x280 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x25b/0xb40 drivers/base/dd.c:658
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
 __device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958
 bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459
 __device_attach+0x2b5/0x400 drivers/base/dd.c:1030
 bus_probe_device+0x180/0x260 drivers/base/bus.c:534
 device_add+0x85b/0xc20 drivers/base/core.c:3683
 usb_new_device+0xa31/0x1630 drivers/usb/core/hub.c:2632
 hub_port_connect drivers/usb/core/hub.c:5501 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5641 [inline]
 port_event drivers/usb/core/hub.c:5801 [inline]
 hub_event+0x2957/0x49c0 drivers/usb/core/hub.c:5883
 process_one_work kernel/workqueue.c:2634 [inline]
 process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293

Freed by task 5814:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4e/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522
 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:164 [inline]
 slab_free_hook mm/slub.c:1806 [inline]
 slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832
 slab_free mm/slub.c:3816 [inline]
 __kmem_cache_free+0xba/0x1f0 mm/slub.c:3829
 smscore_unregister_device+0x603/0x6e0 drivers/media/common/siano/smscoreapi.c:1242
 smsusb_term_device+0x18f/0x220 drivers/media/usb/siano/smsusb.c:349
 smsusb_init_device drivers/media/usb/siano/smsusb.c:491 [inline]
 smsusb_probe+0x1708/0x1da0 drivers/media/usb/siano/smsusb.c:569
 usb_probe_interface+0x5a4/0xb00 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x25b/0xb40 drivers/base/dd.c:658
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
 __device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958
 bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459
 __device_attach+0x2b5/0x400 drivers/base/dd.c:1030
 bus_probe_device+0x180/0x260 drivers/base/bus.c:534
 device_add+0x85b/0xc20 drivers/base/core.c:3683
 usb_set_configuration+0x1a79/0x20c0 drivers/usb/core/message.c:2207
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:238
 usb_probe_device+0x13d/0x280 drivers/usb/core/driver.c:293
 call_driver_probe drivers/base/dd.c:-1 [inline]
 really_probe+0x25b/0xb40 drivers/base/dd.c:658
 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:800
 driver_probe_device+0x4f/0x420 drivers/base/dd.c:830
 __device_attach_driver+0x2ca/0x520 drivers/base/dd.c:958
 bus_for_each_drv+0x24b/0x2d0 drivers/base/bus.c:459
 __device_attach+0x2b5/0x400 drivers/base/dd.c:1030
 bus_probe_device+0x180/0x260 drivers/base/bus.c:534
 device_add+0x85b/0xc20 drivers/base/core.c:3683
 usb_new_device+0xa31/0x1630 drivers/usb/core/hub.c:2632
 hub_port_connect drivers/usb/core/hub.c:5501 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5641 [inline]
 port_event drivers/usb/core/hub.c:5801 [inline]
 hub_event+0x2957/0x49c0 drivers/usb/core/hub.c:5883
 process_one_work kernel/workqueue.c:2634 [inline]
 process_scheduled_works+0xa45/0x15b0 kernel/workqueue.c:2711
 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792
 kthread+0x2fa/0x390 kernel/kthread.c:388
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293

The buggy address belongs to the object at ffff8880604a1000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 152 bytes inside of
 freed 2048-byte region [ffff8880604a1000, ffff8880604a1800)

The buggy address belongs to the physical page:
page:ffffea0001812800 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x604a0
head:ffffea0001812800 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000840 ffff888017842000 dead000000000100 dead000000000122
raw: 0000000000000000 0000000080080008 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 5878, tgid 5878 (syz-executor), ts 98632945023, free_ts 27987823938
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554
 prep_new_page mm/page_alloc.c:1561 [inline]
 get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191
 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457
 alloc_slab_page+0x5d/0x170 mm/slub.c:1876
 allocate_slab mm/slub.c:2023 [inline]
 new_slab+0x87/0x2e0 mm/slub.c:2076
 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230
 __slab_alloc mm/slub.c:3329 [inline]
 __slab_alloc_node mm/slub.c:3382 [inline]
 slab_alloc_node mm/slub.c:3475 [inline]
 __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3524
 __do_kmalloc_node mm/slab_common.c:1006 [inline]
 __kmalloc_node+0xa4/0x230 mm/slab_common.c:1014
 kmalloc_node include/linux/slab.h:620 [inline]
 kzalloc_node include/linux/slab.h:732 [inline]
 qdisc_alloc+0x94/0xa50 net/sched/sch_generic.c:948
 qdisc_create_dflt+0x63/0x430 net/sched/sch_generic.c:1009
 attach_one_default_qdisc net/sched/sch_generic.c:1173 [inline]
 netdev_for_each_tx_queue include/linux/netdevice.h:2520 [inline]
 attach_default_qdiscs net/sched/sch_generic.c:1191 [inline]
 dev_activate+0x397/0x11a0 net/sched/sch_generic.c:1250
 __dev_open+0x338/0x430 net/core/dev.c:1515
 __dev_change_flags+0x20e/0x6a0 net/core/dev.c:8673
 dev_change_flags+0x88/0x1a0 net/core/dev.c:8745
 do_setlink+0xc74/0x3fb0 net/core/rtnetlink.c:2905
 __rtnl_newlink net/core/rtnetlink.c:3703 [inline]
 rtnl_newlink+0x175b/0x2020 net/core/rtnetlink.c:3750
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1154 [inline]
 free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336
 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429
 free_contig_range+0xa1/0x160 mm/page_alloc.c:6369
 destroy_args+0x87/0x770 mm/debug_vm_pgtable.c:1015
 debug_vm_pgtable+0x3cc/0x410 mm/debug_vm_pgtable.c:1395
 do_one_initcall+0x1fd/0x750 init/main.c:1238
 do_initcall_level+0x137/0x1f0 init/main.c:1300
 do_initcalls+0x69/0xd0 init/main.c:1316
 kernel_init_freeable+0x3d2/0x570 init/main.c:1553
 kernel_init+0x1d/0x1c0 init/main.c:1443
 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152
 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293

Memory state around the buggy address:
 ffff8880604a0f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880604a1000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880604a1080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                            ^
 ffff8880604a1100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880604a1180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (39):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/03 01:35 linux-6.6.y 3f5b4c104b7d bc80e4f0 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/02 22:54 linux-6.6.y 3f5b4c104b7d bc80e4f0 .config console log report syz / log C [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2026/03/20 02:59 linux-6.6.y 4fc00fe35d46 2f245add .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2026/03/06 00:06 linux-6.6.y 4fc00fe35d46 31e9c887 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2026/02/24 22:48 linux-6.6.y 7a137e9bfa0e 787dfb7c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2026/02/20 06:25 linux-6.6.y 7a137e9bfa0e 17d780d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2026/01/29 23:48 linux-6.6.y cbb31f77b879 bfa73b7b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2026/01/24 10:22 linux-6.6.y cbb31f77b879 40acda8a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2026/01/06 14:41 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/12/13 14:14 linux-6.6.y 5fa4793a2d2d d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/12/01 12:34 linux-6.6.y 4791134e4aeb d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/12/01 12:33 linux-6.6.y 4791134e4aeb d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/11/25 01:33 linux-6.6.y 1e89a1be4fe9 64219f15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/11/19 18:40 linux-6.6.y 0a805b6ea8cd 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/11/19 18:40 linux-6.6.y 0a805b6ea8cd 26ee5237 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/11/16 22:36 linux-6.6.y 0a805b6ea8cd f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/11/05 07:07 linux-6.6.y 0a805b6ea8cd a6c9c731 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/10/22 03:28 linux-6.6.y f231f248323d 252fbbad .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/09/29 11:32 linux-6.6.y 147338df3487 86341da6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/09/26 19:19 linux-6.6.y 147338df3487 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/09/10 00:54 linux-6.6.y fe9731e10004 fdeaa69b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/09/08 05:12 linux-6.6.y 355bd0b51d2f d291dd2d .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/08/19 13:38 linux-6.6.y bb9c90ab9c5a 254a27c1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/08/06 22:38 linux-6.6.y 3a8ababb8b6a 9a42d6b1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/08/02 00:31 linux-6.6.y 3a8ababb8b6a 7368264b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/08/01 09:52 linux-6.6.y 3a8ababb8b6a 0c075d67 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/18 20:48 linux-6.6.y d96eb99e2f0e 7117feec .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/16 07:44 linux-6.6.y 9247f4e6573a 124ec9cc .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/14 16:55 linux-6.6.y 9247f4e6573a d8fc7335 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/14 16:54 linux-6.6.y 9247f4e6573a d8fc7335 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/10 16:33 linux-6.6.y 59a2de10b81a 956bd956 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/10 02:47 linux-6.6.y a5df3a702b2c 956bd956 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/06 11:01 linux-6.6.y a5df3a702b2c 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/05 06:58 linux-6.6.y 3f5b4c104b7d 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/04 00:19 linux-6.6.y 3f5b4c104b7d 76ad128c .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/03 04:11 linux-6.6.y 3f5b4c104b7d 115ceea7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/02 00:14 linux-6.6.y 3f5b4c104b7d 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/07/02 00:08 linux-6.6.y 3f5b4c104b7d 091a06cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KASAN: slab-use-after-free Read in smscore_getbuffer
2025/10/30 17:12 linux-6.6.y e5bbb12db2c7 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-6-kasan KFENCE: use-after-free read in smscore_getbuffer
* Struck through repros no longer work on HEAD.