general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 8818 Comm: syz.3.756 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 RIP: 0010:set_link_state+0x27/0x11d0 drivers/usb/gadget/udc/dummy_hcd.c:435 Code: 0f 1f 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 50 49 89 fe 48 bb 00 00 00 00 00 fc ff df e8 90 79 cd fa 4c 89 f0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 f7 e8 5b f1 25 fb 4d 8b 26 4c 89 74 24 10 RSP: 0018:ffffc90003647820 EFLAGS: 00010046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000080000 RDX: ffffc9000cfab000 RSI: 0000000000008fd9 RDI: 0000000000008fda RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520006c8ef0 R12: 0000000000000a06 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fd7acc8d6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c276ffa CR3: 000000002d5f2000 CR4: 00000000003526e0 Call Trace: dummy_pullup+0xc1/0x120 drivers/usb/gadget/udc/dummy_hcd.c:914 usb_gadget_disconnect_locked+0x120/0x440 drivers/usb/gadget/udc/core.c:780 gadget_unbind_driver+0xc2/0x3e0 drivers/usb/gadget/udc/core.c:1669 device_remove drivers/base/dd.c:627 [inline] __device_release_driver drivers/base/dd.c:1352 [inline] device_release_driver_internal+0x408/0x6f0 drivers/base/dd.c:1375 bus_remove_device+0x43b/0x520 drivers/base/bus.c:624 device_del+0x51f/0x910 drivers/base/core.c:3889 usb_del_gadget+0x190/0x250 drivers/usb/gadget/udc/core.c:1553 usb_del_gadget_udc+0x15/0x30 drivers/usb/gadget/udc/core.c:1576 platform_remove+0x6d/0xe0 drivers/base/platform.c:1396 device_remove drivers/base/dd.c:627 [inline] __device_release_driver drivers/base/dd.c:1352 [inline] device_release_driver_internal+0x408/0x6f0 drivers/base/dd.c:1375 unbind_store+0x1a1/0x1d0 drivers/base/bus.c:244 kernfs_fop_write_iter+0x3a4/0x520 fs/kernfs/file.c:352 call_write_iter include/linux/fs.h:2018 [inline] new_sync_write fs/read_write.c:491 [inline] vfs_write+0x474/0x9a0 fs/read_write.c:584 ksys_write+0x151/0x260 fs/read_write.c:637 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7fd7abd9de99 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:00007fd7acc8d028 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 00007fd7ac025fa0 RCX: 00007fd7abd9de99 RDX: 000000000000000b RSI: 0000200000000400 RDI: 0000000000000003 RBP: 00007fd7abe33eaf R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fd7ac026038 R14: 00007fd7ac025fa0 R15: 00007ffdffedf358 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:set_link_state+0x27/0x11d0 drivers/usb/gadget/udc/dummy_hcd.c:435 Code: 0f 1f 00 55 41 57 41 56 41 55 41 54 53 48 83 ec 50 49 89 fe 48 bb 00 00 00 00 00 fc ff df e8 90 79 cd fa 4c 89 f0 48 c1 e8 03 <80> 3c 18 00 74 08 4c 89 f7 e8 5b f1 25 fb 4d 8b 26 4c 89 74 24 10 RSP: 0018:ffffc90003647820 EFLAGS: 00010046 RAX: 0000000000000000 RBX: dffffc0000000000 RCX: 0000000000080000 RDX: ffffc9000cfab000 RSI: 0000000000008fd9 RDI: 0000000000008fda RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff520006c8ef0 R12: 0000000000000a06 R13: dffffc0000000000 R14: 0000000000000000 R15: 0000000000000000 FS: 00007fd7acc8d6c0(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000110c276ffa CR3: 000000002d5f2000 CR4: 00000000003526e0 ---------------- Code disassembly (best guess): 0: 0f 1f 00 nopl (%rax) 3: 55 push %rbp 4: 41 57 push %r15 6: 41 56 push %r14 8: 41 55 push %r13 a: 41 54 push %r12 c: 53 push %rbx d: 48 83 ec 50 sub $0x50,%rsp 11: 49 89 fe mov %rdi,%r14 14: 48 bb 00 00 00 00 00 movabs $0xdffffc0000000000,%rbx 1b: fc ff df 1e: e8 90 79 cd fa call 0xfacd79b3 23: 4c 89 f0 mov %r14,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 80 3c 18 00 cmpb $0x0,(%rax,%rbx,1) <-- trapping instruction 2e: 74 08 je 0x38 30: 4c 89 f7 mov %r14,%rdi 33: e8 5b f1 25 fb call 0xfb25f193 38: 4d 8b 26 mov (%r14),%r12 3b: 4c 89 74 24 10 mov %r14,0x10(%rsp)