Dear Linux Developer, Recently when using our tool to fuzz kernel, the following crash was triggered: HEAD commit: 64570fbc14f8 Linux 5.15-rc5 git tree: upstream compiler: clang 12.0.0 console output: https://drive.google.com/file/d/1JxspkioQiZrQQ9BwsRjm5KJVY6z2KCTW/view?usp=sharing Syzlang reproducer: https://drive.google.com/file/d/1b7QJc_OVw-U7ugxWyvisfMbyQe-aBjWZ/view?usp=sharing C reproducer: https://drive.google.com/file/d/1ymwqhBp9VYd7jRdpcfwiqUSUV0BnzCC0/view?usp=sharing kernel config: https://drive.google.com/file/d/1lNwvovjLNrcuyFGrg05IoSmgO5jaKBBJ/view?usp=sharing IMPORTANT: if you fix the bug, please add the following tag to the commit: Reported-by: Wei Chen <harperchen1110@xxxxxxxxx> WARNING: CPU: 0 PID: 8479 at block/genhd.c:537 device_add_disk+0x8aa/0xf20 Modules linked in: CPU: 0 PID: 8479 Comm: syz-executor Not tainted 5.15.0-rc5+ #14 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 RIP: 0010:device_add_disk+0x8aa/0xf20 Code: 00 48 8b 44 24 10 89 18 e8 93 8e 6a fd 4c 89 e7 e8 7b 66 fb ff 4c 89 e7 e8 73 ca 03 00 45 31 f6 e9 b1 fe ff ff e8 76 8e 6a fd <0f> 0b e9 96 fe ff ff e8 6a 8e 6a fd 0f 0b 41 be ea ff ff ff e9 93 RSP: 0018:ffffc9000b297d28 EFLAGS: 00010283 RAX: ffffffff841b4a0a RBX: 0000000000000007 RCX: 0000000000040000 RDX: ffffc90002211000 RSI: 000000000002f3b2 RDI: 000000000002f3b3 RBP: ffff88803017bb00 R08: ffffffff841b4899 R09: ffffed100c7864a2 R10: ffffed100c7864a2 R11: 0000000000000000 R12: ffff88802f915000 R13: 00000000ffffffea R14: 1ffff11005f22a00 R15: 1ffff11005f22a01 FS: 00007ff387033700(0000) GS:ffff888063c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f65c6510000 CR3: 0000000030409000 CR4: 0000000000750ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 PKRU: 55555554 Call Trace: loop_add+0x62d/0x8c0 loop_control_ioctl+0x11d/0x770 __se_sys_ioctl+0x10a/0x190 do_syscall_64+0x3d/0xb0 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7ff389acac4d Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff387032c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ff389bf10a0 RCX: 00007ff389acac4d RDX: 0000000000000000 RSI: 0000000000004c80 RDI: 0000000000000004 RBP: 00007ff387032c90 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000026 R13: 00007fff0e90e49f R14: 00007fff0e90e640 R15: 00007ff387032dc0 Best, Wei
