RBP: 00007ffd572535b0 R08: 0000000000000002 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005 R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 kasan: CONFIG_KASAN_INLINE enabled kasan: GPF could be caused by NULL-ptr deref or user memory access general protection fault: 0000 [#1] PREEMPT SMP KASAN Modules linked in: CPU: 1 PID: 7999 Comm: syz-executor460 Not tainted 4.14.280-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 task: ffff888097f08540 task.stack: ffff888095750000 RIP: 0010:sysfs_do_create_link_sd+0x56/0x120 fs/sysfs/symlink.c:35 RSP: 0018:ffff888095757b48 EFLAGS: 00010202 RAX: dffffc0000000000 RBX: 0000000000000010 RCX: 0000000000001c9a RDX: 0000000000000008 RSI: 0000000000000001 RDI: 0000000000000040 RBP: ffffffff87cbc3e0 R08: ffffffff8b9b3f90 R09: 00000000000400c7 R10: ffff888097f08df0 R11: ffff888097f08540 R12: ffff8880a492b540 R13: ffffffff87cbc3e0 R14: 0000000000000001 R15: ffff88809576e95c FS: 000055555692f300(0000) GS:ffff8880ba500000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000055d3a71518f8 CR3: 00000000a4822000 CR4: 00000000003406e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: sysfs_do_create_link fs/sysfs/symlink.c:80 [inline] sysfs_create_link+0x5f/0xc0 fs/sysfs/symlink.c:92 device_add_disk+0x9f8/0xdc0 block/genhd.c:691 add_disk include/linux/genhd.h:396 [inline] loop_add+0x615/0x830 drivers/block/loop.c:1904 loop_control_ioctl+0x11a/0x3f0 drivers/block/loop.c:2001 vfs_ioctl fs/ioctl.c:46 [inline] file_ioctl fs/ioctl.c:500 [inline] do_vfs_ioctl+0x75a/0xff0 fs/ioctl.c:684 SYSC_ioctl fs/ioctl.c:701 [inline] SyS_ioctl+0x7f/0xb0 fs/ioctl.c:692 do_syscall_64+0x1d5/0x640 arch/x86/entry/common.c:292 entry_SYSCALL_64_after_hwframe+0x46/0xbb RIP: 0033:0x7f6eddf420c9 RSP: 002b:00007ffd57253598 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000002 RCX: 00007f6eddf420c9 RDX: 0000000000000000 RSI: 0000000000004c80 RDI: 0000000000000003 RBP: 00007ffd572535b0 R08: 0000000000000002 R09: 0000000000000001 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000005 R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 Code: 84 a1 00 00 00 e8 eb 63 b1 ff 48 c7 c7 40 ce 04 89 e8 ff 90 80 05 48 8d 7b 30 48 b8 00 00 00 00 00 fc ff df 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 a7 00 00 00 4c 8b 6b 30 4d 85 ed 74 4f e8 b2 RIP: sysfs_do_create_link_sd+0x56/0x120 fs/sysfs/symlink.c:35 RSP: ffff888095757b48 ---[ end trace 1cada1a88fe8097d ]--- ---------------- Code disassembly (best guess): 0: 84 a1 00 00 00 e8 test %ah,-0x18000000(%rcx) 6: eb 63 jmp 0x6b 8: b1 ff mov $0xff,%cl a: 48 c7 c7 40 ce 04 89 mov $0xffffffff8904ce40,%rdi 11: e8 ff 90 80 05 callq 0x5809115 16: 48 8d 7b 30 lea 0x30(%rbx),%rdi 1a: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 21: fc ff df 24: 48 89 fa mov %rdi,%rdx 27: 48 c1 ea 03 shr $0x3,%rdx * 2b: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2f: 0f 85 a7 00 00 00 jne 0xdc 35: 4c 8b 6b 30 mov 0x30(%rbx),%r13 39: 4d 85 ed test %r13,%r13 3c: 74 4f je 0x8d 3e: e8 .byte 0xe8 3f: b2 .byte 0xb2