------------[ cut here ]------------ UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:2902:18 index -3 is out of range for type 's8[1365]' (aka 'signed char[1365]') CPU: 0 UID: 0 PID: 5105 Comm: syz.0.0 Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 ubsan_epilogue lib/ubsan.c:231 [inline] __ubsan_handle_out_of_bounds+0x121/0x150 lib/ubsan.c:429 dbAdjTree+0x377/0x520 fs/jfs/jfs_dmap.c:2902 dbAdjCtl+0x32d/0x9c0 fs/jfs/jfs_dmap.c:2533 dbAllocDmap+0xcb/0x150 fs/jfs/jfs_dmap.c:2044 dbAlloc+0x509/0xca0 fs/jfs/jfs_dmap.c:816 extBalloc fs/jfs/jfs_extent.c:326 [inline] extAlloc+0x4f8/0x1010 fs/jfs/jfs_extent.c:122 jfs_get_block+0x41b/0xe60 fs/jfs/inode.c:248 __block_write_begin_int+0x50c/0x1a70 fs/buffer.c:2121 block_write_begin+0x8f/0x120 fs/buffer.c:2231 jfs_write_begin+0x31/0x70 fs/jfs/inode.c:299 generic_perform_write+0x344/0x6d0 mm/filemap.c:4054 generic_file_write_iter+0xae/0x310 mm/filemap.c:4181 iter_file_splice_write+0xbfa/0x1510 fs/splice.c:743 do_splice_from fs/splice.c:941 [inline] direct_splice_actor+0x11b/0x220 fs/splice.c:1164 splice_direct_to_actor+0x586/0xc80 fs/splice.c:1108 do_splice_direct_actor fs/splice.c:1207 [inline] do_splice_direct+0x289/0x3e0 fs/splice.c:1233 do_sendfile+0x561/0xe10 fs/read_write.c:1388 __do_sys_sendfile64 fs/read_write.c:1455 [inline] __se_sys_sendfile64+0x17c/0x1e0 fs/read_write.c:1441 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f487077dff9 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:00007f48715b2038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f4870936058 RCX: 00007f487077dff9 RDX: 0000000000000000 RSI: 000000000000000b RDI: 000000000000000a RBP: 00007f48707f0296 R08: 0000000000000000 R09: 0000000000000000 R10: 0001000000201005 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007f4870936058 R15: 00007ffff1b4f7f8 ---[ end trace ]---