RBP: 00007f038b15a1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 00007ffcc62e0b7f R14: 00007f038b15a300 R15: 0000000000022000 general protection fault, probably for non-canonical address 0xdffffc0000000003: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000018-0x000000000000001f] CPU: 0 PID: 14268 Comm: syz-executor.4 Not tainted 6.3.0-rc6-next-20230413 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014 RIP: 0010:__ext4_block_zero_page_range+0x14f/0x710 Code: 7f 08 84 c0 0f 85 fe 04 00 00 4d 8d 45 28 b9 0c 00 00 00 48 b8 00 00 00 00 00 fc ff df 2a 4d 14 4c 89 c2 48 d3 e3 48 c1 ea 03 <80> 3c 02 00 0f 85 0a 05 00 00 49 8b 6d 28 48 85 ed 0f 84 71 04 00 RSP: 0018:ffff888045527a08 EFLAGS: 00010217 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000003 RSI: ffffffff81b2f08e RDI: ffff88800d016014 RBP: ffff88800d016000 R08: 000000000000001c R09: ffffffff856c1213 R10: fffffbfff0ad8242 R11: 0000000000000001 R12: 0000000000000081 R13: fffffffffffffff4 R14: 0000000000001000 R15: 0000000000001000 FS: 00007f038b15a700(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f038b159f78 CR3: 0000000042d52000 CR4: 0000000000350ef0 Call Trace: ext4_zero_partial_blocks+0x29d/0x4a0 ext4_fallocate+0x14bd/0x3ad0 vfs_fallocate+0x48d/0xe30 ioctl_preallocate+0x192/0x210 do_vfs_ioctl+0x12b3/0x1690 __x64_sys_ioctl+0x110/0x210 do_syscall_64+0x3f/0x90 entry_SYSCALL_64_after_hwframe+0x72/0xdc RIP: 0033:0x7f038dbe4b19 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f038b15a188 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f038dcf7f60 RCX: 00007f038dbe4b19 RDX: 0000000020000080 RSI: 0000000040305839 RDI: 0000000000000005 RBP: 00007f038b15a1d0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000002 R13: 00007ffcc62e0b7f R14: 00007f038b15a300 R15: 0000000000022000 Modules linked in: loop5: detected capacity change from 0 to 15 ---[ end trace 0000000000000000 ]--- RIP: 0010:__ext4_block_zero_page_range+0x14f/0x710 Code: 7f 08 84 c0 0f 85 fe 04 00 00 4d 8d 45 28 b9 0c 00 00 00 48 b8 00 00 00 00 00 fc ff df 2a 4d 14 4c 89 c2 48 d3 e3 48 c1 ea 03 <80> 3c 02 00 0f 85 0a 05 00 00 49 8b 6d 28 48 85 ed 0f 84 71 04 00 RSP: 0018:ffff888045527a08 EFLAGS: 00010217 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000 RDX: 0000000000000003 RSI: ffffffff81b2f08e RDI: ffff88800d016014 RBP: ffff88800d016000 R08: 000000000000001c R09: ffffffff856c1213 R10: fffffbfff0ad8242 R11: 0000000000000001 R12: 0000000000000081 R13: fffffffffffffff4 R14: 0000000000001000 R15: 0000000000001000 FS: 00007f038b15a700(0000) GS:ffff88806ce00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f038b159f78 CR3: 0000000042d52000 CR4: 0000000000350ef0 loop0: detected capacity change from 0 to 255 loop6: detected capacity change from 0 to 15 loop2: detected capacity change from 0 to 15 loop7: detected capacity change from 0 to 15 ---------------- Code disassembly (best guess): 0: 7f 08 jg 0xa 2: 84 c0 test %al,%al 4: 0f 85 fe 04 00 00 jne 0x508 a: 4d 8d 45 28 lea 0x28(%r13),%r8 e: b9 0c 00 00 00 mov $0xc,%ecx 13: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 1a: fc ff df 1d: 2a 4d 14 sub 0x14(%rbp),%cl 20: 4c 89 c2 mov %r8,%rdx 23: 48 d3 e3 shl %cl,%rbx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 0a 05 00 00 jne 0x53e 34: 49 8b 6d 28 mov 0x28(%r13),%rbp 38: 48 85 ed test %rbp,%rbp 3b: 0f .byte 0xf 3c: 84 71 04 test %dh,0x4(%rcx)