general protection fault in nilfs_mdt_save_to_shadow

Date	Name	Commit	Repro	Result
2026/04/04	upstream (ToT)	3aae9383f42f	C	[report] general protection fault in nilfs_mdt_save_to_shadow_map

Date

Name

Commit

Repro

Result

2026/04/04

upstream (ToT)

3aae9383f42f

[report] general protection fault in nilfs_mdt_save_to_shadow_map

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	general protection fault in nilfs_mdt_save_to_shadow_map nilfs	2	C	error		72	1h03m	22d	0/29	upstream: reported C repro on 2026/03/17 03:14
linux-6.1	BUG: unable to handle kernel paging request in nilfs_mdt_save_to_shadow_map	8	C			7	1d11h	20d	0/3	upstream: reported C repro on 2026/03/19 02:00

loop0: detected capacity change from 0 to 4096 NILFS (loop0): invalid segment: Checksum error in segment payload NILFS (loop0): trying rollback from an earlier position NILFS (loop0): recovery complete general protection fault, probably for non-canonical address 0xdffffc0000000006: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000030-0x0000000000000037] CPU: 1 PID: 4317 Comm: syz.0.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:nilfs_mdt_save_to_shadow_map+0x13d/0x1c0 fs/nilfs2/mdt.c:547 Code: 3f 4c 8d 63 d8 4c 89 e0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 e7 e8 c2 1a b1 fe 4d 8b 24 24 49 83 c4 30 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 a4 1a b1 fe 49 8b 34 24 4c 89 ff RSP: 0018:ffffc90002f3f808 EFLAGS: 00010206 RAX: 0000000000000006 RBX: ffff88805cea0158 RCX: ffff888078955940 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff8d89e36f R09: 1ffffffff1b13c6d R10: dffffc0000000000 R11: fffffbfff1b13c6e R12: 0000000000000030 R13: dffffc0000000000 R14: ffff88807a478540 R15: ffff88805cea1050 FS: 000055558bb3a500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd25366000 CR3: 0000000073d87000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> nilfs_clean_segments+0x15f/0xa30 fs/nilfs2/segment.c:2514 nilfs_ioctl_clean_segments fs/nilfs2/ioctl.c:940 [inline] nilfs_ioctl+0x2052/0x2190 fs/nilfs2/ioctl.c:1304 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f2e08cd9819 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:00007ffd25365198 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f2e08f52fa0 RCX: 00007f2e08cd9819 RDX: 0000200000000640 RSI: 0000000040786e88 RDI: 0000000000000004 RBP: 00007f2e08d6fc91 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f2e08f52fac R14: 00007f2e08f52fa0 R15: 00007f2e08f52fa0 </TASK> Modules linked in: ---[ end trace e39d4f1787574bcd ]--- RIP: 0010:nilfs_mdt_save_to_shadow_map+0x13d/0x1c0 fs/nilfs2/mdt.c:547 Code: 3f 4c 8d 63 d8 4c 89 e0 48 c1 e8 03 42 80 3c 28 00 74 08 4c 89 e7 e8 c2 1a b1 fe 4d 8b 24 24 49 83 c4 30 4c 89 e0 48 c1 e8 03 <42> 80 3c 28 00 74 08 4c 89 e7 e8 a4 1a b1 fe 49 8b 34 24 4c 89 ff RSP: 0018:ffffc90002f3f808 EFLAGS: 00010206 RAX: 0000000000000006 RBX: ffff88805cea0158 RCX: ffff888078955940 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: ffffffff8d89e36f R09: 1ffffffff1b13c6d R10: dffffc0000000000 R11: fffffbfff1b13c6e R12: 0000000000000030 R13: dffffc0000000000 R14: ffff88807a478540 R15: ffff88805cea1050 FS: 000055558bb3a500(0000) GS:ffff8880b9100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd25366000 CR3: 0000000073d87000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: 4c 8d 63 d8 lea -0x28(%rbx),%r12 4: 4c 89 e0 mov %r12,%rax 7: 48 c1 e8 03 shr $0x3,%rax b: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) 10: 74 08 je 0x1a 12: 4c 89 e7 mov %r12,%rdi 15: e8 c2 1a b1 fe call 0xfeb11adc 1a: 4d 8b 24 24 mov (%r12),%r12 1e: 49 83 c4 30 add $0x30,%r12 22: 4c 89 e0 mov %r12,%rax 25: 48 c1 e8 03 shr $0x3,%rax * 29: 42 80 3c 28 00 cmpb $0x0,(%rax,%r13,1) <-- trapping instruction 2e: 74 08 je 0x38 30: 4c 89 e7 mov %r12,%rdi 33: e8 a4 1a b1 fe call 0xfeb11adc 38: 49 8b 34 24 mov (%r12),%rsi 3c: 4c 89 ff mov %r15,%rdi

Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2026/04/03 19:56	linux-5.15.y	91d48252ad4b	4440e7c2	.config	console log	report	syz / log	C		[disk image] [vmlinux] [kernel image] [mounted in repro]	ci2-linux-5-15-kasan	general protection fault in nilfs_mdt_save_to_shadow_map
2026/04/03 18:48	linux-5.15.y	91d48252ad4b	4440e7c2	.config	console log	report	syz / log	C		[disk image] [vmlinux] [kernel image] [mounted in repro]	ci2-linux-5-15-kasan	general protection fault in nilfs_mdt_save_to_shadow_map
2026/04/03 17:43	linux-5.15.y	91d48252ad4b	4440e7c2	.config	console log	report	syz / log	C		[disk image] [vmlinux] [kernel image] [mounted in repro]	ci2-linux-5-15-kasan	general protection fault in nilfs_mdt_save_to_shadow_map
2026/04/03 16:26	linux-5.15.y	91d48252ad4b	4440e7c2	.config	console log	report	syz / log	C		[disk image] [vmlinux] [kernel image] [mounted in repro]	ci2-linux-5-15-kasan	general protection fault in nilfs_mdt_save_to_shadow_map
2026/04/07 04:58	linux-5.15.y	91d48252ad4b	4440e7c2	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-linux-5-15-kasan	general protection fault in nilfs_mdt_save_to_shadow_map
2026/04/06 23:53	linux-5.15.y	91d48252ad4b	4440e7c2	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-linux-5-15-kasan	general protection fault in nilfs_mdt_save_to_shadow_map
2026/04/03 15:23	linux-5.15.y	91d48252ad4b	4440e7c2	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-linux-5-15-kasan	general protection fault in nilfs_mdt_save_to_shadow_map
2026/04/03 15:20	linux-5.15.y	91d48252ad4b	4440e7c2	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-linux-5-15-kasan	general protection fault in nilfs_mdt_save_to_shadow_map
2026/04/03 15:19	linux-5.15.y	91d48252ad4b	4440e7c2	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci2-linux-5-15-kasan	general protection fault in nilfs_mdt_save_to_shadow_map