kasan: CONFIG_KASAN_INLINE enabled
kasan: GPF could be caused by NULL-ptr deref or user memory accessgeneral protection fault: 0000 [#1] PREEMPT SMP KASAN
Dumping ftrace buffer:
   (ftrace buffer empty)
Modules linked in:
CPU: 1 PID: 28201 Comm: syz-executor7 Not tainted 4.4.145-g2241aa9 #78
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
task: ffff8801cecbb000 task.stack: ffff8801c7cc0000
RIP: 0010:[<ffffffff8251968d>]  [<ffffffff8251968d>] loop_validate_file+0x20d/0x400 drivers/block/loop.c:667
RSP: 0018:ffff8801c7cc7b70  EFLAGS: 00010206
RAX: 0000000000000036 RBX: dffffc0000000000 RCX: ffffc90004bf6000
RDX: 0000000000000087 RSI: ffffffff8251965d RDI: 00000000000001b0
RBP: ffff8801c7cc7b88 R08: ffff8801cecbb928 R09: 0000000000000001
R10: 0000000000000000 R11: ffff8801cecbb000 R12: 0000000000000000
R13: ffff8801d9c13980 R14: ffff8801d9c13980 R15: ffff8801d6b4c158
FS:  00007f38241e1700(0000) GS:ffff8801db300000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020000080 CR3: 00000001d8956000 CR4: 00000000001606f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Stack:
 ffff8801d6b4c000 ffff8801d98e0000 0000000000000014 ffff8801c7cc7c18
 ffffffff8251fbed 0000000b0000004c 0000000100000006 0000000000000000
 0000000300000001 ffff8801d6b4c018 0000000041b58ab3 ffffffff84208310
Call Trace:
 [<ffffffff8251fbed>] loop_change_fd drivers/block/loop.c:713 [inline]
 [<ffffffff8251fbed>] lo_ioctl+0x3ed/0x16c0 drivers/block/loop.c:1370
 [<ffffffff81dbb628>] __blkdev_driver_ioctl block/ioctl.c:288 [inline]
 [<ffffffff81dbb628>] blkdev_ioctl+0x7b8/0x19c0 block/ioctl.c:584
 [<ffffffff815d637e>] block_ioctl+0xde/0x120 fs/block_dev.c:1625
 [<ffffffff8155bfdf>] vfs_ioctl fs/ioctl.c:43 [inline]
 [<ffffffff8155bfdf>] file_ioctl fs/ioctl.c:470 [inline]
 [<ffffffff8155bfdf>] do_vfs_ioctl+0x63f/0xf40 fs/ioctl.c:605
 [<ffffffff8155c96f>] SYSC_ioctl fs/ioctl.c:622 [inline]
 [<ffffffff8155c96f>] SyS_ioctl+0x8f/0xc0 fs/ioctl.c:613
 [<ffffffff838c84e5>] entry_SYSCALL_64_fastpath+0x22/0x9e
Code: 00 00 00 48 89 f8 48 c1 e8 03 80 3c 18 00 0f 85 f7 01 00 00 4d 8b a4 24 f0 00 00 00 49 8d bc 24 b0 01 00 00 48 89 f8 48 c1 e8 03 <80> 3c 18 00 0f 85 cc 01 00 00 4d 8b a4 24 b0 01 00 00 4c 89 e0 
RIP  [<ffffffff8251968d>] loop_validate_file+0x20d/0x400 drivers/block/loop.c:667
 RSP <ffff8801c7cc7b70>
---[ end trace f1837f330233e85c ]---