==================================================================
BUG: KASAN: slab-use-after-free in find_endpoint+0x2a3/0x2c0 drivers/usb/gadget/udc/dummy_hcd.c:1618
Read of size 1 at addr ffff8880754cc6ab by task swapper/1/0

CPU: 1 UID: 0 PID: 0 Comm: swapper/1 Tainted: G             L      syzkaller #0 PREEMPT(full) 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/05/2026
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
 find_endpoint+0x2a3/0x2c0 drivers/usb/gadget/udc/dummy_hcd.c:1618
 dummy_timer+0x500/0x3700 drivers/usb/gadget/udc/dummy_hcd.c:1890
 __run_hrtimer kernel/time/hrtimer.c:2067 [inline]
 __hrtimer_run_queues+0x462/0x9c0 kernel/time/hrtimer.c:2124
 hrtimer_run_softirq+0x1ca/0x360 kernel/time/hrtimer.c:2141
 handle_softirqs+0x1e6/0x9d0 kernel/softirq.c:645
 __do_softirq kernel/softirq.c:679 [inline]
 invoke_softirq kernel/softirq.c:519 [inline]
 __irq_exit_rcu+0x16a/0x210 kernel/softirq.c:758
 irq_exit_rcu+0x9/0x30 kernel/softirq.c:775
 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:finish_task_switch.isra.0+0x2ca/0x10d0 kernel/sched/core.c:5377
Code: b6 0a 00 00 41 c7 87 20 0e 00 00 00 00 00 00 e9 47 04 00 00 49 8d 7f 48 e8 83 e9 fb 09 e8 4e 1e 3d 00 fb 48 8d bb 10 17 00 00 <48> b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 0f b6 04 02 84
RSP: 0018:ffffc900001a7c38 EFLAGS: 00000206
RAX: 0000000000e8ff7d RBX: ffff88801f6c4b00 RCX: 0000000000000000
RDX: 0000000000000001 RSI: ffffffff8e3ebf9c RDI: ffff88801f6c6210
RBP: ffffc900001a7c90 R08: 0000000000000001 R09: 0000000000000000
R10: 0000000000000001 R11: ffffffff81d73ed9 R12: ffff888033212580
R13: 0000000000000001 R14: ffffffff91454404 R15: ffff8880b853bf00
 context_switch kernel/sched/core.c:5529 [inline]
 __schedule+0x1261/0x6920 kernel/sched/core.c:7276
 schedule_idle+0x54/0x80 kernel/sched/core.c:7394
 do_idle+0x365/0x5b0 kernel/sched/idle.c:384
 cpu_startup_entry+0x4f/0x60 kernel/sched/idle.c:454
 start_secondary+0x21d/0x2d0 arch/x86/kernel/smpboot.c:312
 common_startup_64+0x13e/0x158
 </TASK>

Allocated by task 6972:
 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]
 __do_kmalloc_node mm/slub.c:5414 [inline]
 __kmalloc_noprof+0x32f/0x840 mm/slub.c:5439
 _kmalloc_noprof include/linux/slab.h:995 [inline]
 usb_copy_descriptors+0xcd/0x320 drivers/usb/gadget/config.c:82
 f_midi2_bind+0x1dad/0x2770 drivers/usb/gadget/function/f_midi2.c:2025
 usb_add_function+0x219/0x890 drivers/usb/gadget/composite.c:333
 configfs_composite_bind+0xd83/0x1960 drivers/usb/gadget/configfs.c:1802
 gadget_bind_driver+0x28c/0xbf0 drivers/usb/gadget/udc/core.c:1662
 call_driver_probe drivers/base/dd.c:628 [inline]
 really_probe+0x241/0xa60 drivers/base/dd.c:706
 __driver_probe_device+0x210/0x460 drivers/base/dd.c:868
 driver_probe_device+0x4a/0x140 drivers/base/dd.c:898
 __driver_attach+0x21f/0x5b0 drivers/base/dd.c:1292
 bus_for_each_dev+0x13e/0x1d0 drivers/base/bus.c:383
 bus_add_driver+0x305/0x5b0 drivers/base/bus.c:763
 driver_register+0x1e2/0x360 drivers/base/driver.c:174
 usb_gadget_register_driver_owner+0x132/0x210 drivers/usb/gadget/udc/core.c:1752
 gadget_dev_desc_UDC_store+0x1b0/0x2e0 drivers/usb/gadget/configfs.c:300
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6af/0x1050 fs/read_write.c:687
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 7188:
 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:2748 [inline]
 slab_free mm/slub.c:6499 [inline]
 kfree+0x22b/0x6d0 mm/slub.c:6792
 usb_free_descriptors include/linux/usb/gadget.h:903 [inline]
 usb_free_all_descriptors+0x81/0x1a0 drivers/usb/gadget/config.c:151
 purge_configs_funcs+0x285/0x510 drivers/usb/gadget/configfs.c:1600
 configfs_composite_unbind+0xae/0x210 drivers/usb/gadget/configfs.c:1846
 gadget_unbind_driver+0x20c/0x4f0 drivers/usb/gadget/udc/core.c:1724
 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
 driver_detach+0xd8/0x1b0 drivers/base/dd.c:1435
 bus_remove_driver+0x13b/0x2e0 drivers/base/bus.c:832
 driver_unregister+0x76/0xb0 drivers/base/driver.c:202
 usb_gadget_unregister_driver+0x49/0x70 drivers/usb/gadget/udc/core.c:1784
 unregister_gadget drivers/usb/gadget/configfs.c:263 [inline]
 gadget_dev_desc_UDC_store+0x170/0x2e0 drivers/usb/gadget/configfs.c:290
 flush_write_buffer fs/configfs/file.c:207 [inline]
 configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229
 new_sync_write fs/read_write.c:595 [inline]
 vfs_write+0x6af/0x1050 fs/read_write.c:687
 ksys_write+0x12a/0x250 fs/read_write.c:739
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff8880754cc600
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 171 bytes inside of
 freed 256-byte region [ffff8880754cc600, ffff8880754cc700)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880754cd600 pfn:0x754cc
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0xfff00000000240(workingset|head|node=0|zone=1|lastcpupid=0x7ff)
page_type: f5(slab)
raw: 00fff00000000240 ffff88801c02fb40 ffffea0001ea8c10 ffffea00009ba910
raw: ffff8880754cd600 000000000010000d 00000000f5000000 0000000000000000
head: 00fff00000000240 ffff88801c02fb40 ffffea0001ea8c10 ffffea00009ba910
head: ffff8880754cd600 000000000010000d 00000000f5000000 0000000000000000
head: 00fff00000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff
head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4976, tgid 4976 (udevd), ts 70895580949
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0xfd/0x120 mm/page_alloc.c:1871
 prep_new_page mm/page_alloc.c:1879 [inline]
 get_page_from_freelist+0x110d/0x35d0 mm/page_alloc.c:3943
 __alloc_frozen_pages_noprof+0x2eb/0x3300 mm/page_alloc.c:5436
 alloc_slab_page mm/slub.c:3347 [inline]
 allocate_slab mm/slub.c:3462 [inline]
 new_slab+0xa9/0x6e0 mm/slub.c:3513
 refill_objects+0xe3/0x410 mm/slub.c:7410
 refill_sheaf mm/slub.c:2885 [inline]
 __pcs_replace_empty_main+0x35e/0x650 mm/slub.c:4774
 alloc_from_pcs mm/slub.c:4850 [inline]
 slab_alloc_node mm/slub.c:4984 [inline]
 __kmalloc_cache_noprof+0x4f4/0x6d0 mm/slub.c:5559
 _kmalloc_noprof include/linux/slab.h:991 [inline]
 inode_doinit_use_xattr+0x54/0x330 security/selinux/hooks.c:1379
 inode_doinit_with_dentry+0x10fc/0x1340 security/selinux/hooks.c:1574
 selinux_d_instantiate+0x26/0x40 security/selinux/hooks.c:6685
 security_d_instantiate+0x14c/0x1b0 security/security.c:3703
 d_splice_alias_ops+0xd7/0x15b0 fs/dcache.c:3249
 kernfs_iop_lookup+0x23f/0x2d0 fs/kernfs/dir.c:1288
 lookup_open+0xa79/0x1990 fs/namei.c:4528
 open_last_lookups fs/namei.c:4767 [inline]
 path_openat+0xa2c/0x2440 fs/namei.c:4997
 do_file_open+0x20e/0x430 fs/namei.c:5029
page last free pid 5807 tgid 5806 ts 70859274561 stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 __free_pages_prepare mm/page_alloc.c:1418 [inline]
 __free_frozen_pages+0x79f/0x10f0 mm/page_alloc.c:2962
 qlink_free mm/kasan/quarantine.c:163 [inline]
 qlist_free_all+0x47/0xf0 mm/kasan/quarantine.c:179
 kasan_quarantine_reduce+0x1a0/0x1f0 mm/kasan/quarantine.c:286
 __kasan_slab_alloc+0x69/0x90 mm/kasan/common.c:350
 kasan_slab_alloc include/linux/kasan.h:253 [inline]
 slab_post_alloc_hook mm/slub.c:4683 [inline]
 slab_alloc_node mm/slub.c:4996 [inline]
 __kmalloc_cache_noprof+0x278/0x6d0 mm/slub.c:5559
 _kmalloc_noprof include/linux/slab.h:991 [inline]
 _kzalloc_noprof include/linux/slab.h:1312 [inline]
 ref_tracker_alloc+0x190/0x590 lib/ref_tracker.c:270
 __netns_tracker_alloc include/net/net_namespace.h:370 [inline]
 netns_tracker_alloc include/net/net_namespace.h:379 [inline]
 get_net_track include/net/net_namespace.h:396 [inline]
 sk_alloc+0x2e9/0xe80 net/core/sock.c:2324
 __netlink_create+0x5e/0x2c0 net/netlink/af_netlink.c:627
 netlink_create+0x29b/0x610 net/netlink/af_netlink.c:685
 __sock_create+0x339/0x860 net/socket.c:1676
 sock_create net/socket.c:1734 [inline]
 __sys_socket_create net/socket.c:1771 [inline]
 __sys_socket+0x14d/0x260 net/socket.c:1818
 __do_sys_socket net/socket.c:1832 [inline]
 __se_sys_socket net/socket.c:1830 [inline]
 __x64_sys_socket+0x72/0xb0 net/socket.c:1830
 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline]
 do_syscall_64+0x123/0x790 arch/x86/entry/syscall_64.c:84
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Memory state around the buggy address:
 ffff8880754cc580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880754cc600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880754cc680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                  ^
 ffff8880754cc700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880754cc780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
----------------
Code disassembly (best guess):
   0:	b6 0a                	mov    $0xa,%dh
   2:	00 00                	add    %al,(%rax)
   4:	41 c7 87 20 0e 00 00 	movl   $0x0,0xe20(%r15)
   b:	00 00 00 00
   f:	e9 47 04 00 00       	jmp    0x45b
  14:	49 8d 7f 48          	lea    0x48(%r15),%rdi
  18:	e8 83 e9 fb 09       	call   0x9fbe9a0
  1d:	e8 4e 1e 3d 00       	call   0x3d1e70
  22:	fb                   	sti
  23:	48 8d bb 10 17 00 00 	lea    0x1710(%rbx),%rdi
* 2a:	48 b8 00 00 00 00 00 	movabs $0xdffffc0000000000,%rax <-- trapping instruction
  31:	fc ff df
  34:	48 89 fa             	mov    %rdi,%rdx
  37:	48 c1 ea 03          	shr    $0x3,%rdx
  3b:	0f b6 04 02          	movzbl (%rdx,%rax,1),%eax
  3f:	84                   	.byte 0x84