loop0: detected capacity change from 0 to 32768 ------------[ 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 6.11.0-rc5-syzkaller-00207-gfb24560f31f9 #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:93 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:119 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:2125 __block_write_begin fs/buffer.c:2174 [inline] block_write_begin+0x9b/0x1e0 fs/buffer.c:2235 jfs_write_begin+0x31/0x70 fs/jfs/inode.c:299 generic_perform_write+0x399/0x840 mm/filemap.c:4019 generic_file_write_iter+0xaf/0x310 mm/filemap.c:4147 __kernel_write_iter+0x40d/0x900 fs/read_write.c:523 dump_emit_page fs/coredump.c:893 [inline] dump_user_range+0x4e0/0x950 fs/coredump.c:954 elf_core_dump+0x3de6/0x4720 fs/binfmt_elf.c:2116 do_coredump+0x1b04/0x2a30 fs/coredump.c:767 get_signal+0x13fa/0x1740 kernel/signal.c:2902 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x100/0x230 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd1a3779eb9 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:00007fd1a45f5038 EFLAGS: 00000246 ORIG_RAX: 0000000000000129 RAX: 0000000000000000 RBX: 00007fd1a3915f80 RCX: 00007fd1a3779eb9 RDX: 000000000000001f RSI: 0000000000000004 RDI: 0000000000000003 RBP: 00007fd1a37e793e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000020000140 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 00007fd1a3915f80 R15: 00007ffc3300a1d8 ---[ end trace ]---