general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 1379 Comm: syz.7.239 Tainted: G W syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2946 [inline] RIP: 0010:update_sit_entry+0x5b4/0xf70 fs/f2fs/segment.c:2256 Code: 00 00 49 8d 5d 18 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 0a 72 90 ff 48 8b 1b 48 03 5d b0 48 89 d8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 a9 08 00 00 44 0f b6 33 44 89 f0 44 8b RSP: 0018:ffffc90000ed6a18 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88810b7fa780 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000ed6a98 R08: ffff88810b7fa780 R09: 0000000000000003 R10: 00000000ffffffff R11: 0000000000000002 R12: dffffc0000000000 R13: ffff8881101449b8 R14: 0000000000000000 R15: ffff8881085fa000 FS: 00007fa26ea166c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000020000000b000 CR3: 000000013e0a2000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: f2fs_allocate_data_block+0x15e8/0x3240 fs/f2fs/segment.c:3457 do_write_page+0x13c/0xab0 fs/f2fs/segment.c:3547 f2fs_outplace_write_data+0xf6/0x240 fs/f2fs/segment.c:3621 f2fs_do_write_data_page+0xf6a/0x1590 fs/f2fs/data.c:2739 f2fs_write_single_data_page+0x1090/0x1760 fs/f2fs/data.c:2861 f2fs_write_cache_pages fs/f2fs/data.c:3112 [inline] __f2fs_write_data_pages fs/f2fs/data.c:3262 [inline] f2fs_write_data_pages+0x17df/0x28e0 fs/f2fs/data.c:3289 do_writepages+0x473/0x6c0 mm/page-writeback.c:2388 filemap_fdatawrite_wbc+0x1f4/0x250 mm/filemap.c:409 __filemap_fdatawrite_range mm/filemap.c:442 [inline] file_write_and_wait_range+0x14d/0x220 mm/filemap.c:819 f2fs_do_sync_file+0x5b7/0x1bb0 fs/f2fs/file.c:280 f2fs_sync_file+0x103/0x150 fs/f2fs/file.c:397 vfs_fsync_range+0x190/0x1a0 fs/sync.c:188 generic_write_sync include/linux/fs.h:3038 [inline] f2fs_file_write_iter+0x60a/0x29a0 fs/f2fs/file.c:4821 call_write_iter include/linux/fs.h:2212 [inline] new_sync_write fs/read_write.c:507 [inline] vfs_write+0x835/0xfd0 fs/read_write.c:594 ksys_pwrite64 fs/read_write.c:701 [inline] __do_sys_pwrite64 fs/read_write.c:711 [inline] __se_sys_pwrite64 fs/read_write.c:708 [inline] __x64_sys_pwrite64+0x197/0x220 fs/read_write.c:708 x64_sys_call+0xa6/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:19 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: 0033:0x7fa26fffd799 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:00007fa26ea16028 EFLAGS: 00000246 ORIG_RAX: 0000000000000012 RAX: ffffffffffffffda RBX: 00007fa270277180 RCX: 00007fa26fffd799 RDX: 000000000000fdef RSI: 0000200000000140 RDI: 0000000000000005 RBP: 00007fa270093c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000e7c R11: 0000000000000246 R12: 0000000000000000 R13: 00007fa270277218 R14: 00007fa270277180 R15: 00007ffd3b6ae548 Modules linked in: ---[ end trace c1d5070258e62c18 ]--- RIP: 0010:f2fs_test_and_set_bit fs/f2fs/f2fs.h:2946 [inline] RIP: 0010:update_sit_entry+0x5b4/0xf70 fs/f2fs/segment.c:2256 Code: 00 00 49 8d 5d 18 48 89 d8 48 c1 e8 03 42 80 3c 20 00 74 08 48 89 df e8 0a 72 90 ff 48 8b 1b 48 03 5d b0 48 89 d8 48 c1 e8 03 <42> 0f b6 04 20 84 c0 0f 85 a9 08 00 00 44 0f b6 33 44 89 f0 44 8b RSP: 0018:ffffc90000ed6a18 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff88810b7fa780 RDX: 0000000000000002 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc90000ed6a98 R08: ffff88810b7fa780 R09: 0000000000000003 R10: 00000000ffffffff R11: 0000000000000002 R12: dffffc0000000000 R13: ffff8881101449b8 R14: 0000000000000000 R15: ffff8881085fa000 FS: 00007fa26ea166c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f0e07b672f8 CR3: 000000013e0a2000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 49 8d 5d 18 lea 0x18(%r13),%rbx 6: 48 89 d8 mov %rbx,%rax 9: 48 c1 e8 03 shr $0x3,%rax d: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) 12: 74 08 je 0x1c 14: 48 89 df mov %rbx,%rdi 17: e8 0a 72 90 ff call 0xff907226 1c: 48 8b 1b mov (%rbx),%rbx 1f: 48 03 5d b0 add -0x50(%rbp),%rbx 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 42 0f b6 04 20 movzbl (%rax,%r12,1),%eax <-- trapping instruction 2f: 84 c0 test %al,%al 31: 0f 85 a9 08 00 00 jne 0x8e0 37: 44 0f b6 33 movzbl (%rbx),%r14d 3b: 44 89 f0 mov %r14d,%eax 3e: 44 rex.R 3f: 8b .byte 0x8b