[syzbot] [usb?] KASAN: slab-use-after-free Read in usa49_glocont_callback

syzbot <[email protected]>
Newsgroups org.kernel.vger.linux-usb,org.kernel.vger.linux-kernel
Message-ID <[email protected]>
Hello,

syzbot found the following issue on:

HEAD commit:    06cf61899d64 Merge tag 'x86-urgent-2026-08-08' of git://gi..
git tree:       upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=14094079580000
kernel config:  https://syzkaller.appspot.com/x/.config?x=c44651ea7dd2f307
dashboard link: https://syzkaller.appspot.com/bug?extid=e5e28c3e953b2eebb16e
compiler:       gcc (Debian 14.2.0-19) 14.2.0, GNU ld (GNU Binutils for Debian) 2.44

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/260ea970a68e/disk-06cf6189.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/0005e8a7195f/vmlinux-06cf6189.xz
kernel image: https://storage.googleapis.com/syzbot-assets/f061ed2152ca/bzImage-06cf6189.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: [email protected]

==================================================================
BUG: KASAN: slab-use-after-free in usa49_glocont_callback+0x232/0x260 drivers/usb/serial/keyspan.c:1045
Read of size 4 at addr ffff888028940cb0 by task syz.4.480/7762

CPU: 0 UID: 0 PID: 7762 Comm: syz.4.480 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:94 [inline]
 dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0x13d/0x4b0 mm/kasan/report.c:482
 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595
 usa49_glocont_callback+0x232/0x260 drivers/usb/serial/keyspan.c:1045
 __usb_hcd_giveback_urb+0x38d/0x610 drivers/usb/core/hcd.c:1657
 usb_hcd_giveback_urb+0x3ca/0x4a0 drivers/usb/core/hcd.c:1741
 dummy_timer+0xdb2/0x36f0 drivers/usb/gadget/udc/dummy_hcd.c:2019
 __run_hrtimer kernel/time/hrtimer.c:2032 [inline]
 __hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2096
 hrtimer_run_softirq+0x17d/0x2c0 kernel/time/hrtimer.c:2113
 handle_softirqs+0x1ea/0x9b0 kernel/softirq.c:622
 __do_softirq kernel/softirq.c:656 [inline]
 invoke_softirq kernel/softirq.c:496 [inline]
 __irq_exit_rcu+0x162/0x210 kernel/softirq.c:735
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:752
 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1062 [inline]
 sysvec_apic_timer_interrupt+0xa3/0xc0 arch/x86/kernel/apic/apic.c:1062
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:674
RIP: 0010:rcu_read_unlock+0x26/0x60 include/linux/rcupdate.h:869
Code: 90 90 90 90 e8 8b 74 37 09 85 c0 75 18 48 c7 c7 00 82 be 8e 48 8d 35 00 00 00 00 e8 94 bb 62 ff e9 ff 1c 6c ff e8 0a 28 6b ff <84> c0 75 df e8 61 74 37 09 85 c0 74 d6 80 3d 45 f6 85 0e 00 75 cd
RSP: 0018:ffffc9000611f428 EFLAGS: 00000286
RAX: 0000000000000001 RBX: ffff888036ba3700 RCX: 0000000000000000
RDX: 0000000000000000 RSI: ffffffff8c400300 RDI: ffffffff8e470920
RBP: dffffc0000000000 R08: 0000000085239a3f R09: 0000000000000007
R10: 0000000000000200 R11: 0000000000000000 R12: ffff8880447b8cc0
R13: ffffed10088f72fa R14: ffffffff8283cbb9 R15: ffff8880368b0800
 percpu_ref_tryget_many include/linux/percpu-refcount.h:250 [inline]
 percpu_ref_tryget include/linux/percpu-refcount.h:266 [inline]
 css_tryget include/linux/cgroup_refcnt.h:45 [inline]
 css_tryget include/linux/cgroup_refcnt.h:42 [inline]
 get_mem_cgroup_from_mm+0x29c/0x5e0 mm/memcontrol.c:1145
 __mem_cgroup_charge+0x1a/0x1c0 mm/memcontrol.c:5142
 mem_cgroup_charge include/linux/memcontrol.h:657 [inline]
 shmem_alloc_and_add_folio+0x451/0xd40 mm/shmem.c:1969
 shmem_get_folio_gfp+0x6ad/0x1910 mm/shmem.c:2512
 shmem_fault+0x1f9/0xa20 mm/shmem.c:2713
 __do_fault+0x10b/0x440 mm/memory.c:5425
 do_read_fault mm/memory.c:5860 [inline]
 do_fault+0xa99/0x1750 mm/memory.c:5994
 do_pte_missing mm/memory.c:4566 [inline]
 handle_pte_fault mm/memory.c:6379 [inline]
 __handle_mm_fault+0x187d/0x2a00 mm/memory.c:6517
 handle_mm_fault+0x37b/0xa30 mm/memory.c:6686
 faultin_page mm/gup.c:1126 [inline]
 __get_user_pages+0x1178/0x32a0 mm/gup.c:1428
 populate_vma_page_range+0x267/0x3f0 mm/gup.c:1860
 __mm_populate+0x107/0x3a0 mm/gup.c:1963
 mm_populate include/linux/mm.h:4171 [inline]
 vm_mmap_pgoff+0x37f/0x470 mm/util.c:586
 ksys_mmap_pgoff+0xe4/0x610 mm/mmap.c:606
 __do_sys_mmap arch/x86/kernel/sys_x86_64.c:89 [inline]
 __se_sys_mmap arch/x86/kernel/sys_x86_64.c:82 [inline]
 __x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:82
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9fce59e0d9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f9fcf481028 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f9fce826270 RCX: 00007f9fce59e0d9
RDX: b635773f06ebbeee RSI: 0000000000b36000 RDI: 0000200000000000
RBP: 00007f9fce635024 R08: ffffffffffffffff R09: 0000000000000000
R10: 0000000000008031 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9fce826308 R14: 00007f9fce826270 R15: 00007ffcd6d18da8
 </TASK>

Allocated by task 24:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
 __kasan_kmalloc+0xaa/0xb0 mm/kasan/common.c:415
 kasan_kmalloc include/linux/kasan.h:263 [inline]
 __kmalloc_cache_noprof+0x2e5/0x6c0 mm/slub.c:5489
 _kmalloc_noprof include/linux/slab.h:988 [inline]
 _kzalloc_noprof include/linux/slab.h:1309 [inline]
 keyspan_port_probe+0xbc/0xdd0 drivers/usb/serial/keyspan.c:2891
 usb_serial_device_probe+0x106/0x3e0 drivers/usb/serial/bus.c:47
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x64/0x160 drivers/base/bus.c:620
 device_add+0x121d/0x1970 drivers/base/core.c:3772
 usb_serial_probe.cold+0x257e/0x29f8 drivers/usb/serial/usb-serial.c:1147
 usb_probe_interface+0x303/0x8f0 drivers/usb/core/driver.c:396
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x64/0x160 drivers/base/bus.c:620
 device_add+0x121d/0x1970 drivers/base/core.c:3772
 usb_set_configuration+0xd97/0x1c60 drivers/usb/core/message.c:2268
 usb_generic_driver_probe+0xa1/0xe0 drivers/usb/core/generic.c:250
 usb_probe_device+0xef/0x400 drivers/usb/core/driver.c:291
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x20e/0x450 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __device_attach_driver+0x1df/0x320 drivers/base/dd.c:1026
 bus_for_each_drv+0x159/0x1e0 drivers/base/bus.c:500
 __device_attach+0x1e4/0x4d0 drivers/base/dd.c:1098
 device_initial_probe+0xaf/0xd0 drivers/base/dd.c:1153
 bus_probe_device+0x64/0x160 drivers/base/bus.c:620
 device_add+0x121d/0x1970 drivers/base/core.c:3772
 usb_new_device.part.0+0xcc2/0x1686 drivers/usb/core/hub.c:2703
 usb_new_device include/linux/workqueue.h:714 [inline]
 hub_port_connect drivers/usb/core/hub.c:5575 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5715 [inline]
 port_event drivers/usb/core/hub.c:5879 [inline]
 hub_event.cold+0x1e3/0xe90 drivers/usb/core/hub.c:5961
 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
 process_scheduled_works kernel/workqueue.c:3405 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Freed by task 24:
 kasan_save_stack+0x30/0x50 mm/kasan/common.c:57
 kasan_save_track+0x14/0x30 mm/kasan/common.c:78
 kasan_save_free_info+0x3b/0x70 mm/kasan/generic.c:584
 poison_slab_object mm/kasan/common.c:253 [inline]
 __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:285
 kasan_slab_free include/linux/kasan.h:235 [inline]
 slab_free_hook mm/slub.c:2677 [inline]
 slab_free mm/slub.c:6377 [inline]
 kfree+0x22b/0x6c0 mm/slub.c:6692
 usb_serial_device_remove+0x146/0x1a0 drivers/usb/serial/bus.c:97
 device_remove+0xcb/0x180 drivers/base/dd.c:616
 __device_release_driver drivers/base/dd.c:1349 [inline]
 device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
 bus_remove_device+0x2bc/0x560 drivers/base/bus.c:664
 device_del+0x376/0x9b0 drivers/base/core.c:3961
 usb_serial_disconnect+0x21e/0x490 drivers/usb/serial/usb-serial.c:1195
 usb_unbind_interface+0x1dd/0x9e0 drivers/usb/core/driver.c:458
 device_remove drivers/base/dd.c:618 [inline]
 device_remove+0x12a/0x180 drivers/base/dd.c:610
 __device_release_driver drivers/base/dd.c:1349 [inline]
 device_release_driver_internal+0x44e/0x620 drivers/base/dd.c:1372
 bus_remove_device+0x2bc/0x560 drivers/base/bus.c:664
 device_del+0x376/0x9b0 drivers/base/core.c:3961
 usb_disable_device+0x367/0x810 drivers/usb/core/message.c:1478
 usb_disconnect+0x2e2/0x9a0 drivers/usb/core/hub.c:2345
 hub_port_connect drivers/usb/core/hub.c:5415 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5715 [inline]
 port_event drivers/usb/core/hub.c:5879 [inline]
 hub_event+0x1bb1/0x4420 drivers/usb/core/hub.c:5961
 process_one_work+0xa23/0x1940 kernel/workqueue.c:3322
 process_scheduled_works kernel/workqueue.c:3405 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3486
 kthread+0x370/0x450 kernel/kthread.c:436
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

The buggy address belongs to the object at ffff888028940c00
 which belongs to the cache kmalloc-192 of size 192
The buggy address is located 176 bytes inside of
 freed 192-byte region [ffff888028940c00, ffff888028940cc0)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28940
flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000000 ffff88813fe213c0 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0xd2cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 4807713744, free_ts 4805273634
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1859
 prep_new_page mm/page_alloc.c:1867 [inline]
 get_page_from_freelist+0xf48/0x3530 mm/page_alloc.c:3946
 __alloc_frozen_pages_noprof+0x299/0x2dc0 mm/page_alloc.c:5304
 alloc_slab_page mm/slub.c:3266 [inline]
 allocate_slab mm/slub.c:3380 [inline]
 new_slab+0xa2/0x640 mm/slub.c:3426
 refill_objects+0xe3/0x410 mm/slub.c:7310
 refill_sheaf mm/slub.c:2804 [inline]
 __pcs_replace_empty_main+0x376/0x680 mm/slub.c:4675
 alloc_from_pcs mm/slub.c:4773 [inline]
 slab_alloc_node mm/slub.c:4905 [inline]
 __kmalloc_cache_node_noprof+0x542/0x6c0 mm/slub.c:5504
 _kmalloc_node_noprof include/linux/slab.h:1193 [inline]
 alloc_worker kernel/workqueue.c:2706 [inline]
 init_rescuer+0x19f/0x550 kernel/workqueue.c:5706
 __alloc_workqueue+0xe4e/0x1940 kernel/workqueue.c:5906
 alloc_workqueue_va kernel/workqueue.c:5946 [inline]
 alloc_workqueue_noprof+0xc7/0x130 kernel/workqueue.c:5962
 nvmet_init+0x14a/0x240 drivers/nvme/target/core.c:1970
 do_one_initcall+0x11d/0x700 init/main.c:1347
 do_initcall_level init/main.c:1409 [inline]
 do_initcalls init/main.c:1425 [inline]
 do_basic_setup init/main.c:1445 [inline]
 kernel_init_freeable+0x6ea/0x7b0 init/main.c:1658
 kernel_init+0x1f/0x1e0 init/main.c:1548
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
page last free pid 2 tgid 2 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 __free_pages_prepare mm/page_alloc.c:1406 [inline]
 __free_frozen_pages+0x79f/0x1090 mm/page_alloc.c:2950
 __kasan_populate_vmalloc_do mm/kasan/shadow.c:393 [inline]
 __kasan_populate_vmalloc+0x1ea/0x210 mm/kasan/shadow.c:424
 kasan_populate_vmalloc include/linux/kasan.h:580 [inline]
 alloc_vmap_area+0x95d/0x2bb0 mm/vmalloc.c:2145
 __get_vm_area_node+0x1ca/0x330 mm/vmalloc.c:3248
 __vmalloc_node_range_noprof+0x228/0x1630 mm/vmalloc.c:4064
 __vmalloc_node_noprof+0xad/0xf0 mm/vmalloc.c:4165
 alloc_thread_stack_node kernel/fork.c:359 [inline]
 dup_task_struct kernel/fork.c:929 [inline]
 copy_process+0x7fb/0x8030 kernel/fork.c:2115
 kernel_clone+0x176/0x9d0 kernel/fork.c:2748
 kernel_thread+0xdb/0x120 kernel/fork.c:2809
 create_kthread kernel/kthread.c:459 [inline]
 kthreadd+0x498/0x7a0 kernel/kthread.c:817
 ret_from_fork+0x72b/0xd50 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff888028940b80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
 ffff888028940c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888028940c80: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
                                     ^
 ffff888028940d00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888028940d80: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
   0:	90                   	nop
   1:	90                   	nop
   2:	90                   	nop
   3:	90                   	nop
   4:	e8 8b 74 37 09       	call   0x9377494
   9:	85 c0                	test   %eax,%eax
   b:	75 18                	jne    0x25
   d:	48 c7 c7 00 82 be 8e 	mov    $0xffffffff8ebe8200,%rdi
  14:	48 8d 35 00 00 00 00 	lea    0x0(%rip),%rsi        # 0x1b
  1b:	e8 94 bb 62 ff       	call   0xff62bbb4
  20:	e9 ff 1c 6c ff       	jmp    0xff6c1d24
  25:	e8 0a 28 6b ff       	call   0xff6b2834
* 2a:	84 c0                	test   %al,%al <-- trapping instruction
  2c:	75 df                	jne    0xd
  2e:	e8 61 74 37 09       	call   0x9377494
  33:	85 c0                	test   %eax,%eax
  35:	74 d6                	je     0xd
  37:	80 3d 45 f6 85 0e 00 	cmpb   $0x0,0xe85f645(%rip)        # 0xe85f683
  3e:	75 cd                	jne    0xd


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
syzbot engineers can be reached at [email protected].

syzbot will keep track of this issue. See:
https://goo.gl/tpsmEJ#status for how to communicate with syzbot.

If the report is already addressed, let syzbot know by replying with:
#syz fix: exact-commit-title

If you want to overwrite report's subsystems, reply with:
#syz set subsystems: new-subsystem
(See the list of subsystem names on the web dashboard)

If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.