syz.4.2405: attempt to access beyond end of device nbd4: rw=0, sector=256, nr_sectors = 1 limit=0 UDF-fs: error (device nbd4): udf_read_tagged: read failed, block=256, location=256 ------------[ cut here ]------------ WARNING: fs/buffer.c:1125 at __getblk_slow fs/buffer.c:1125 [inline], CPU#1: syz.4.2405/15919 WARNING: fs/buffer.c:1125 at bdev_getblk+0x580/0x660 fs/buffer.c:1461, CPU#1: syz.4.2405/15919 Modules linked in: CPU: 1 UID: 0 PID: 15919 Comm: syz.4.2405 Not tainted 6.16.0-rc5-next-20250708-syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 RIP: 0010:__getblk_slow fs/buffer.c:1125 [inline] RIP: 0010:bdev_getblk+0x580/0x660 fs/buffer.c:1461 Code: 26 fb ff ff e8 a1 0c 78 ff 48 c7 c7 e0 26 ba 8b 48 c7 c6 c6 70 cd 8d 4c 89 fa 4c 89 e9 e8 c8 b0 df fe eb bd e8 81 0c 78 ff 90 <0f> 0b 90 48 b8 00 00 00 00 00 fc ff df 41 80 3c 07 00 74 08 48 89 RSP: 0018:ffffc900036976b0 EFLAGS: 00010293 RAX: ffffffff8247efaf RBX: ffff888023110018 RCX: ffff88802d613c00 RDX: 0000000000000000 RSI: 0000000000000200 RDI: 0000000000000000 RBP: 0000000000000200 R08: 0000000000000000 R09: ffffffff8217434d R10: 0000000000000406 R11: 0000000000000000 R12: ffff888023110968 R13: ffff888023110000 R14: 0000000000000200 R15: 1ffff11004622003 FS: 00007f71c53d56c0(0000) GS:ffff88812589f000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000004a00 CR3: 0000000061cac000 CR4: 00000000003526f0 Call Trace: __bread_gfp+0x89/0x3c0 fs/buffer.c:1515 sb_bread include/linux/buffer_head.h:346 [inline] udf_read_tagged+0xad/0xe00 fs/udf/misc.c:199 udf_check_anchor_block+0x99/0x550 fs/udf/super.c:1903 udf_scan_anchors fs/udf/super.c:1964 [inline] udf_load_vrs+0x96d/0xf20 fs/udf/super.c:2024 udf_fill_super+0x5ad/0x17a0 fs/udf/super.c:2192 get_tree_bdev_flags+0x40b/0x4d0 fs/super.c:1681 vfs_get_tree+0x8f/0x2b0 fs/super.c:1804 do_new_mount+0x2a2/0x9e0 fs/namespace.c:3805 do_mount fs/namespace.c:4133 [inline] __do_sys_mount fs/namespace.c:4344 [inline] __se_sys_mount+0x317/0x410 fs/namespace.c:4321 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0x3b0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f71c758e929 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f71c53d5038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5 RAX: ffffffffffffffda RBX: 00007f71c77b6080 RCX: 00007f71c758e929 RDX: 0000200000000080 RSI: 0000200000004a00 RDI: 0000200000000000 RBP: 00007f71c7610b39 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000002008087 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f71c77b6080 R15: 00007ffc7957be68