smsusb:smsusb_onresponse: error, urb status -71, 0 bytes smsusb:smsusb_onresponse: error, urb status -71, 0 bytes smsusb:smsusb_onresponse: error, urb status -71, 0 bytes ================================================================== BUG: KASAN: use-after-free in dummy_timer+0x29cb/0x31e0 drivers/usb/gadget/udc/dummy_hcd.c:1844 Read of size 4 at addr ffff88805497a154 by task syz.2.435/6410 CPU: 1 PID: 6410 Comm: syz.2.435 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: 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 dummy_timer+0x29cb/0x31e0 drivers/usb/gadget/udc/dummy_hcd.c:1844 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x53a/0x7f0 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x339/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 RIP: 0010:finish_lock_switch+0x134/0x280 kernel/sched/core.c:4804 Code: be ff ff ff ff e8 4c 80 67 08 85 c0 74 4a 4d 85 ff 75 66 0f 1f 44 00 00 48 89 df e8 b6 eb 70 08 e8 41 e0 2a 00 fb 48 83 c4 08 <5b> 41 5c 41 5d 41 5e 41 5f 5d c3 48 89 df e8 c9 09 fe ff 43 80 3c RSP: 0018:ffffc90003a072c8 EFLAGS: 00000282 RAX: e9e7b7d06cfe7c00 RBX: ffff8880b913a340 RCX: e9e7b7d06cfe7c00 RDX: dffffc0000000000 RSI: ffffffff8a2b2780 RDI: ffffffff8a79f780 RBP: 1ffff11017227613 R08: ffff8880b913a343 R09: 1ffff11017227468 R10: dffffc0000000000 R11: ffffed1017227469 R12: 1ffff110172275c1 R13: dffffc0000000000 R14: ffff8880b913ae08 R15: 0000000000000000 finish_task_switch+0x12f/0x640 kernel/sched/core.c:4921 context_switch kernel/sched/core.c:5052 [inline] __schedule+0x11f7/0x43c0 kernel/sched/core.c:6395 schedule+0x11b/0x1e0 kernel/sched/core.c:6478 schedule_timeout+0xbd/0x2d0 kernel/time/timer.c:1890 unix_wait_for_peer+0x1f2/0x2e0 net/unix/af_unix.c:1315 unix_dgram_sendmsg+0x1083/0x18a0 net/unix/af_unix.c:1910 sock_sendmsg_nosec net/socket.c:706 [inline] __sock_sendmsg net/socket.c:718 [inline] ____sys_sendmsg+0x5b7/0x8f0 net/socket.c:2445 ___sys_sendmsg+0x236/0x2e0 net/socket.c:2499 __sys_sendmmsg+0x2ba/0x500 net/socket.c:2585 __do_sys_sendmmsg net/socket.c:2614 [inline] __se_sys_sendmmsg net/socket.c:2611 [inline] __x64_sys_sendmmsg+0x9c/0xb0 net/socket.c:2611 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fa01c215eb9 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:00007fa01a471028 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007fa01c490fa0 RCX: 00007fa01c215eb9 RDX: 0000000000000651 RSI: 0000200000000000 RDI: 0000000000000005 RBP: 00007fa01c283c1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa01c491038 R14: 00007fa01c490fa0 R15: 00007ffcfca69748 Allocated by task 5402: 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+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] smsusb_init_device drivers/media/usb/siano/smsusb.c:397 [inline] smsusb_probe+0x8a1/0x1de0 drivers/media/usb/siano/smsusb.c:569 usb_probe_interface+0x5c5/0xb20 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429 __device_attach+0x2a8/0x480 drivers/base/dd.c:979 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3412 usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2165 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+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429 __device_attach+0x2a8/0x480 drivers/base/dd.c:979 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3412 usb_new_device+0xd65/0x1660 drivers/usb/core/hub.c:2632 hub_port_connect drivers/usb/core/hub.c:5497 [inline] hub_port_connect_change drivers/usb/core/hub.c:5637 [inline] port_event drivers/usb/core/hub.c:5799 [inline] hub_event+0x2e4a/0x55e0 drivers/usb/core/hub.c:5881 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Freed by task 5402: 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+0xea/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kfree+0xef/0x2a0 mm/slub.c:4564 smsusb_term_device+0x1ac/0x220 drivers/media/usb/siano/smsusb.c:352 smsusb_init_device drivers/media/usb/siano/smsusb.c:491 [inline] smsusb_probe+0x1746/0x1de0 drivers/media/usb/siano/smsusb.c:569 usb_probe_interface+0x5c5/0xb20 drivers/usb/core/driver.c:396 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429 __device_attach+0x2a8/0x480 drivers/base/dd.c:979 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3412 usb_set_configuration+0x1991/0x1fd0 drivers/usb/core/message.c:2165 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+0x284/0xc80 drivers/base/dd.c:595 __driver_probe_device+0x18c/0x330 drivers/base/dd.c:755 driver_probe_device+0x4f/0x420 drivers/base/dd.c:785 __device_attach_driver+0x2b0/0x500 drivers/base/dd.c:907 bus_for_each_drv+0x184/0x210 drivers/base/bus.c:429 __device_attach+0x2a8/0x480 drivers/base/dd.c:979 bus_probe_device+0xbc/0x1e0 drivers/base/bus.c:489 device_add+0xa00/0xfb0 drivers/base/core.c:3412 usb_new_device+0xd65/0x1660 drivers/usb/core/hub.c:2632 hub_port_connect drivers/usb/core/hub.c:5497 [inline] hub_port_connect_change drivers/usb/core/hub.c:5637 [inline] port_event drivers/usb/core/hub.c:5799 [inline] hub_event+0x2e4a/0x55e0 drivers/usb/core/hub.c:5881 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 insert_work+0x54/0x3d0 kernel/workqueue.c:1366 __queue_work+0x9c5/0xd50 kernel/workqueue.c:1532 queue_work_on+0x124/0x1f0 kernel/workqueue.c:1559 __usb_hcd_giveback_urb+0x35f/0x520 drivers/usb/core/hcd.c:1674 dummy_timer+0x8a8/0x31e0 drivers/usb/gadget/udc/dummy_hcd.c:1988 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x53a/0x7f0 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x339/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 Second to last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 insert_work+0x54/0x3d0 kernel/workqueue.c:1366 __queue_work+0x9c5/0xd50 kernel/workqueue.c:1532 queue_work_on+0x124/0x1f0 kernel/workqueue.c:1559 __usb_hcd_giveback_urb+0x35f/0x520 drivers/usb/core/hcd.c:1674 dummy_timer+0x8a8/0x31e0 drivers/usb/gadget/udc/dummy_hcd.c:1988 call_timer_fn+0x17b/0x540 kernel/time/timer.c:1451 expire_timers kernel/time/timer.c:1496 [inline] __run_timers+0x53a/0x7f0 kernel/time/timer.c:1767 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1780 handle_softirqs+0x339/0x830 kernel/softirq.c:576 __do_softirq kernel/softirq.c:610 [inline] invoke_softirq kernel/softirq.c:450 [inline] __irq_exit_rcu+0x13b/0x230 kernel/softirq.c:659 irq_exit_rcu+0x5/0x20 kernel/softirq.c:671 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1108 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1108 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:676 The buggy address belongs to the object at ffff88805497a000 which belongs to the cache kmalloc-4k of size 4096 The buggy address is located 340 bytes inside of 4096-byte region [ffff88805497a000, ffff88805497b000) The buggy address belongs to the page: page:ffffea0001525e00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x54978 head:ffffea0001525e00 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888016c42140 raw: 0000000000000000 0000000000040004 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 0x1d2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 5825, ts 183388357284, free_ts 178645902946 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5487 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+0x80a/0xdd0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] __kmalloc_node_track_caller+0x1fc/0x3a0 mm/slub.c:4963 kmalloc_reserve net/core/skbuff.c:356 [inline] __alloc_skb+0x22c/0x750 net/core/skbuff.c:427 alloc_skb include/linux/skbuff.h:1162 [inline] nsim_dev_trap_skb_build drivers/net/netdevsim/dev.c:664 [inline] nsim_dev_trap_report drivers/net/netdevsim/dev.c:721 [inline] nsim_dev_trap_report_work+0x2a1/0xb40 drivers/net/netdevsim/dev.c:762 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 kthread+0x436/0x520 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 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 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] kmem_cache_alloc_node+0x12d/0x2d0 mm/slub.c:3261 __alloc_skb+0xf4/0x750 net/core/skbuff.c:415 alloc_skb include/linux/skbuff.h:1162 [inline] nlmsg_new include/net/netlink.h:953 [inline] inet_netconf_notify_devconf+0x16f/0x230 net/ipv4/devinet.c:2121 __devinet_sysctl_unregister net/ipv4/devinet.c:2630 [inline] devinet_sysctl_unregister net/ipv4/devinet.c:2654 [inline] inetdev_destroy net/ipv4/devinet.c:326 [inline] inetdev_event+0x702/0x1370 net/ipv4/devinet.c:1611 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2061 [inline] call_netdevice_notifiers net/core/dev.c:2075 [inline] unregister_netdevice_many+0x1049/0x19f0 net/core/dev.c:11134 default_device_exit_batch+0x364/0x3c0 net/core/dev.c:11667 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x791/0xba0 net/core/net_namespace.c:635 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 Memory state around the buggy address: ffff88805497a000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805497a080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805497a100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805497a180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88805497a200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ---------------- Code disassembly (best guess): 0: be ff ff ff ff mov $0xffffffff,%esi 5: e8 4c 80 67 08 call 0x8678056 a: 85 c0 test %eax,%eax c: 74 4a je 0x58 e: 4d 85 ff test %r15,%r15 11: 75 66 jne 0x79 13: 0f 1f 44 00 00 nopl 0x0(%rax,%rax,1) 18: 48 89 df mov %rbx,%rdi 1b: e8 b6 eb 70 08 call 0x870ebd6 20: e8 41 e0 2a 00 call 0x2ae066 25: fb sti 26: 48 83 c4 08 add $0x8,%rsp * 2a: 5b pop %rbx <-- trapping instruction 2b: 41 5c pop %r12 2d: 41 5d pop %r13 2f: 41 5e pop %r14 31: 41 5f pop %r15 33: 5d pop %rbp 34: c3 ret 35: 48 89 df mov %rbx,%rdi 38: e8 c9 09 fe ff call 0xfffe0a06 3d: 43 rex.XB 3e: 80 .byte 0x80 3f: 3c .byte 0x3c