------------[ cut here ]------------ kernel BUG at fs/ext4/extents.c:2140! invalid opcode: 0000 [#1] PREEMPT SMP KASAN CPU: 1 PID: 1676 Comm: syz.8.55 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:ext4_ext_insert_extent+0x477e/0x47c0 fs/ext4/extents.c:2140 Code: ff 44 89 f1 80 e1 07 fe c1 38 c1 0f 8c a5 e8 ff ff 4c 89 f7 e8 73 78 d4 ff e9 98 e8 ff ff e8 f9 49 95 ff 0f 0b e8 f2 49 95 ff <0f> 0b e8 eb 49 95 ff 0f 0b 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 19 RSP: 0018:ffffc900047e6140 EFLAGS: 00010293 RAX: ffffffff81d47cee RBX: ffff88812541f400 RCX: ffff888131f662c0 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000009 RBP: ffffc900047e62f0 R08: ffff88811f936c7f R09: 1ffff11023f26d8f R10: dffffc0000000000 R11: ffffed1023f26d90 R12: 0000000000000009 R13: ffff888132d72468 R14: ffff88812541f43c R15: 0000000000000009 FS: 00007f35eb5f66c0(0000) GS:ffff8881f7100000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f35eb5f5c00 CR3: 000000011bb1a000 CR4: 00000000003506a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: ext4_ext_map_blocks+0x186c/0x61e0 fs/ext4/extents.c:4368 ext4_map_blocks+0x988/0x1b30 fs/ext4/inode.c:674 _ext4_get_block+0x1ea/0x540 fs/ext4/inode.c:817 ext4_get_block_unwritten+0x2a/0x40 fs/ext4/inode.c:848 ext4_block_write_begin+0x563/0x1160 fs/ext4/inode.c:1102 ext4_write_begin+0x65a/0x12e0 fs/ext4/ext4_jbd2.h:-1 ext4_da_write_begin+0x321/0xbf0 fs/ext4/inode.c:2988 generic_perform_write+0x2b7/0x690 mm/filemap.c:3870 ext4_buffered_write_iter+0x4ed/0x670 fs/ext4/file.c:270 ext4_file_write_iter+0x440/0x1540 fs/ext4/file.c:-1 __kernel_write+0x510/0x950 fs/read_write.c:539 __dump_emit+0x246/0x370 fs/coredump.c:880 dump_emit+0x383/0x3f0 fs/coredump.c:917 dump_user_range+0x86/0x1c0 fs/coredump.c:954 elf_core_dump+0x2a8f/0x2fd0 fs/binfmt_elf.c:2285 do_coredump+0x1452/0x2950 fs/coredump.c:831 get_signal+0x38d/0x1480 kernel/signal.c:2893 arch_do_signal_or_restart+0xdf/0x11c0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:154 [inline] exit_to_user_mode_loop+0xa7/0xe0 kernel/entry/common.c:178 exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214 irqentry_exit_to_user_mode+0x9/0x10 kernel/entry/common.c:320 irqentry_exit+0x12/0x40 kernel/entry/common.c:411 exc_page_fault+0x5e/0xb0 arch/x86/mm/fault.c:1563 asm_exc_page_fault+0x27/0x30 arch/x86/include/asm/idtentry.h:606 RIP: 0033:0x7f35eb791eb9 Code: Unable to access opcode bytes at RIP 0x7f35eb791e8f. RSP: 002b:00007f35eb5f5fd8 EFLAGS: 00010206 RAX: 0000000000000000 RBX: 00007f35eba0cfa0 RCX: 00007f35eb791eb9 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000a000 RBP: 00007f35eb7ffc1f R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007f35eba0d038 R14: 00007f35eba0cfa0 R15: 00007ffc51818368 Modules linked in: ---[ end trace 2775e1614769e9fa ]--- RIP: 0010:ext4_ext_insert_extent+0x477e/0x47c0 fs/ext4/extents.c:2140 Code: ff 44 89 f1 80 e1 07 fe c1 38 c1 0f 8c a5 e8 ff ff 4c 89 f7 e8 73 78 d4 ff e9 98 e8 ff ff e8 f9 49 95 ff 0f 0b e8 f2 49 95 ff <0f> 0b e8 eb 49 95 ff 0f 0b 89 d9 80 e1 07 80 c1 03 38 c1 0f 8c 19 RSP: 0018:ffffc900047e6140 EFLAGS: 00010293 RAX: ffffffff81d47cee RBX: ffff88812541f400 RCX: ffff888131f662c0 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 0000000000000009 RBP: ffffc900047e62f0 R08: ffff88811f936c7f R09: 1ffff11023f26d8f R10: dffffc0000000000 R11: ffffed1023f26d90 R12: 0000000000000009 R13: ffff888132d72468 R14: ffff88812541f43c R15: 0000000000000009 FS: 00007f35eb5f66c0(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffc51814da0 CR3: 000000011bb1a000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400