UDC core: USB Raw Gadget: couldn't find an available UDC or it's busy misc raw-gadget: fail, usb_gadget_register_driver returned -16 ================================================================== BUG: KASAN: slab-use-after-free in string_nocheck lib/vsprintf.c:646 [inline] BUG: KASAN: slab-use-after-free in string+0x20f/0x2b0 lib/vsprintf.c:728 Read of size 1 at addr ffff888106361460 by task syz.0.199/1123 CPU: 1 UID: 0 PID: 1123 Comm: syz.0.199 Not tainted syzkaller #0 7f3b23dcf55806c758f3cdeb9210fc77c27c120f Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:94 dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120 print_address_description+0x71/0x210 mm/kasan/report.c:377 print_report+0x4a/0x70 mm/kasan/report.c:481 kasan_report+0x162/0x1a0 mm/kasan/report.c:594 __asan_report_load1_noabort+0x18/0x20 mm/kasan/report_generic.c:378 string_nocheck lib/vsprintf.c:646 [inline] string+0x20f/0x2b0 lib/vsprintf.c:728 vsnprintf+0xe65/0x1ad0 lib/vsprintf.c:2803 snprintf+0xe9/0x140 lib/vsprintf.c:2938 set_dev_info drivers/base/core.c:4950 [inline] dev_vprintk_emit+0x313/0x400 drivers/base/core.c:4960 dev_printk_emit+0xef/0x150 drivers/base/core.c:4973 __dev_printk+0x17f/0x1b0 drivers/base/core.c:4985 _dev_err+0x11f/0x180 drivers/base/core.c:5028 raw_process_ep0_io+0x54b/0x7a0 drivers/usb/gadget/legacy/raw_gadget.c:730 raw_ioctl_ep0_write drivers/usb/gadget/legacy/raw_gadget.c:767 [inline] raw_ioctl+0x226c/0x37a0 drivers/usb/gadget/legacy/raw_gadget.c:1313 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:907 [inline] __se_sys_ioctl+0x132/0x1b0 fs/ioctl.c:893 __x64_sys_ioctl+0x7f/0xa0 fs/ioctl.c:893 x64_sys_call+0x1878/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:17 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e RIP: 0033:0x7f25ce59dcab Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007f25cf52af50 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f25ce59dcab RDX: 00007f25cf52afd0 RSI: 0000000040085503 RDI: 0000000000000003 RBP: 00007f25cf52afd0 R08: 000000000000002c R09: 0000000000000000 R10: 0000000000000003 R11: 0000000000000246 R12: 00007f25cf52afd8 R13: 0000200000000000 R14: 00007f25ce825fa0 R15: 00007ffdd9c52928 Allocated by task 1: kasan_save_stack mm/kasan/common.c:49 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:70 kasan_save_alloc_info+0x3a/0x50 mm/kasan/generic.c:565 poison_kmalloc_redzone mm/kasan/common.c:379 [inline] __kasan_kmalloc+0x96/0xb0 mm/kasan/common.c:396 kasan_kmalloc include/linux/kasan.h:261 [inline] __do_kmalloc_node mm/slub.c:4395 [inline] __kmalloc_node_track_caller_noprof+0x24e/0x4f0 mm/slub.c:4414 kvasprintf+0xf1/0x260 lib/kasprintf.c:25 kvasprintf_const+0xf6/0x250 lib/kasprintf.c:49 kobject_set_name_vargs+0x65/0x120 lib/kobject.c:274 dev_set_name+0xe3/0x140 drivers/base/core.c:3495 usb_add_gadget+0x436/0x780 drivers/usb/gadget/udc/core.c:1446 usb_add_gadget_udc_release drivers/usb/gadget/udc/core.c:1504 [inline] usb_add_gadget_udc+0x11e/0x160 drivers/usb/gadget/udc/core.c:1551 dummy_udc_probe+0x6ea/0x7f0 drivers/usb/gadget/udc/dummy_hcd.c:1102 platform_probe+0x17a/0x200 drivers/base/platform.c:1404 call_driver_probe drivers/base/dd.c:-1 [inline] really_probe+0x2e1/0x8b0 drivers/base/dd.c:657 __driver_probe_device+0x193/0x280 drivers/base/dd.c:799 driver_probe_device+0x54/0x3f0 drivers/base/dd.c:829 __device_attach_driver+0x2f1/0x4b0 drivers/base/dd.c:957 bus_for_each_drv+0x264/0x300 drivers/base/bus.c:459 __device_attach+0x2c4/0x3c0 drivers/base/dd.c:1029 device_initial_probe+0x1e/0x30 drivers/base/dd.c:1078 bus_probe_device+0x18b/0x270 drivers/base/bus.c:534 device_add+0x7fd/0xbf0 drivers/base/core.c:3692 platform_device_add+0x464/0x6c0 drivers/base/platform.c:716 dummy_hcd_init+0xce2/0x1230 drivers/usb/gadget/udc/dummy_hcd.c:2876 do_one_initcall+0x1e8/0x6a0 init/main.c:1406 do_initcall_level+0x174/0x2e5 init/main.c:1468 do_initcalls+0x7e/0x160 init/main.c:1484 do_basic_setup+0x95/0xb0 init/main.c:1503 kernel_init_freeable+0x2b1/0x400 init/main.c:1717 kernel_init+0x21/0x1e0 init/main.c:1606 ret_from_fork+0x67/0xa0 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 1134: kasan_save_stack mm/kasan/common.c:49 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:70 kasan_save_free_info+0x44/0x50 mm/kasan/generic.c:579 poison_slab_object mm/kasan/common.c:249 [inline] __kasan_slab_free+0x5f/0x80 mm/kasan/common.c:266 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2445 [inline] slab_free mm/slub.c:4714 [inline] kfree+0x158/0x440 mm/slub.c:4875 kfree_const+0x3d/0x50 mm/util.c:49 kobject_cleanup lib/kobject.c:695 [inline] kobject_release lib/kobject.c:720 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x21f/0x2a0 lib/kobject.c:737 put_device+0x23/0x40 drivers/base/core.c:3800 usb_put_gadget include/linux/usb/gadget.h:512 [inline] usb_del_gadget_udc+0x25/0x30 drivers/usb/gadget/udc/core.c:1594 dummy_udc_remove+0x5c/0x70 drivers/usb/gadget/udc/dummy_hcd.c:1123 platform_remove+0x7e/0xb0 drivers/base/platform.c:1424 device_remove drivers/base/dd.c:567 [inline] __device_release_driver drivers/base/dd.c:1272 [inline] device_release_driver_internal+0x4ad/0x830 drivers/base/dd.c:1295 device_driver_detach+0x3f/0x50 drivers/base/dd.c:1331 unbind_store+0x1ab/0x1f0 drivers/base/bus.c:244 drv_attr_store+0x91/0xb0 drivers/base/bus.c:125 sysfs_kf_write+0x141/0x160 fs/sysfs/file.c:136 kernfs_fop_write_iter+0x319/0x510 fs/kernfs/file.c:352 new_sync_write fs/read_write.c:591 [inline] vfs_write+0x762/0xfd0 fs/read_write.c:684 ksys_write+0x145/0x260 fs/read_write.c:737 __do_sys_write fs/read_write.c:749 [inline] __se_sys_write fs/read_write.c:746 [inline] __x64_sys_write+0x7f/0x90 fs/read_write.c:746 x64_sys_call+0x271c/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:2 do_syscall_x64 arch/x86/entry/common.c:47 [inline] do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78 entry_SYSCALL_64_after_hwframe+0x76/0x7e The buggy address belongs to the object at ffff888106361460 which belongs to the cache kmalloc-16 of size 16 The buggy address is located 0 bytes inside of freed 16-byte region [ffff888106361460, ffff888106361470) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x106361 anon flags: 0x4000000000000000(zone=1) page_type: f5(slab) raw: 4000000000000000 ffff888100041640 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000800080 00000001f5000000 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 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 1, tgid 1 (swapper/0), ts 4198627093, free_ts 0 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook+0x37d/0x3b0 mm/page_alloc.c:1863 prep_new_page+0x2d/0x180 mm/page_alloc.c:1871 get_page_from_freelist+0x4aea/0x4ba0 mm/page_alloc.c:3948 __alloc_pages_noprof+0x35a/0x7e0 mm/page_alloc.c:5315 alloc_slab_page+0x6b/0x1e0 mm/slub.c:-1 allocate_slab+0x69/0x430 mm/slub.c:2687 new_slab mm/slub.c:2741 [inline] ___slab_alloc+0x591/0x8c0 mm/slub.c:3934 __slab_alloc mm/slub.c:4025 [inline] __slab_alloc_node mm/slub.c:4078 [inline] slab_alloc_node mm/slub.c:4239 [inline] __do_kmalloc_node mm/slub.c:4394 [inline] __kmalloc_node_track_caller_noprof+0x2e3/0x4f0 mm/slub.c:4414 kstrdup+0x4d/0x130 mm/util.c:70 kstrdup_const+0x45/0x60 mm/util.c:93 __kernfs_new_node+0xaa/0x740 fs/kernfs/dir.c:624 kernfs_new_node+0x154/0x280 fs/kernfs/dir.c:704 kernfs_create_dir_ns+0x4b/0x130 fs/kernfs/dir.c:1065 sysfs_create_dir_ns+0x127/0x210 fs/sysfs/dir.c:59 create_dir lib/kobject.c:73 [inline] kobject_add_internal+0x71f/0xc20 lib/kobject.c:240 kobject_add_varg lib/kobject.c:374 [inline] kobject_add+0x169/0x240 lib/kobject.c:426 page_owner free stack trace missing Memory state around the buggy address: ffff888106361300: 00 04 fc fc 00 01 fc fc 00 05 fc fc 00 05 fc fc ffff888106361380: 00 00 fc fc 00 04 fc fc 00 05 fc fc 00 05 fc fc >ffff888106361400: 00 04 fc fc 00 04 fc fc 00 00 fc fc fa fb fc fc ^ ffff888106361480: 00 05 fc fc 00 07 fc fc 00 00 fc fc 00 01 fc fc ffff888106361500: 00 01 fc fc 00 01 fc fc 00 01 fc fc 00 01 fc fc ================================================================== gadget w]n: fail, usb_ep_queue returned -108