------------[ 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: 5110 Comm: syz.0.0 Not tainted 6.12.0-rc3-syzkaller-00454-gdb87114dcf13 #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:
 <TASK>
 __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
 dbAllocBits+0x4ea/0x990 fs/jfs/jfs_dmap.c:2193
 dbAllocDmap+0x6d/0x150 fs/jfs/jfs_dmap.c:2034
 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
 __kernel_write_iter+0x42a/0x940 fs/read_write.c:616
 dump_emit_page fs/coredump.c:884 [inline]
 dump_user_range+0x4e0/0x950 fs/coredump.c:945
 elf_core_dump+0x3e85/0x4770 fs/binfmt_elf.c:2121
 do_coredump+0x2162/0x2ec0 fs/coredump.c:758
 get_signal+0x13fc/0x1740 kernel/signal.c:2902
 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:337
 exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
 exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
 irqentry_exit_to_user_mode+0x79/0x280 kernel/entry/common.c:231
 exc_page_fault+0x590/0x8c0 arch/x86/mm/fault.c:1542
 asm_exc_page_fault+0x26/0x30 arch/x86/include/asm/idtentry.h:623
RIP: 0033:0x0
Code: Unable to access opcode bytes at 0xffffffffffffffd6.
RSP: 002b:0000000020000308 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f8169135f80 RCX: 00007f8168f7dff9
RDX: 0000000020000340 RSI: 0000000020000300 RDI: 0000000000000080
RBP: 00007f8168ff0296 R08: 0000000020000b40 R09: 0000000020000b40
R10: 0000000020000380 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f8169135f80 R15: 00007ffd03010ee8
 </TASK>
---[ end trace ]---