UBSAN: shift-out-of-bounds in fs/jfs/jfs_extent.c:314:16 shift exponent -1 is negative CPU: 1 PID: 8027 Comm: syz-executor.5 Not tainted 6.1.0-rc1-next-20221021-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 ubsan_epilogue+0xb/0x50 lib/ubsan.c:151 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x187 lib/ubsan.c:322 extHint.cold-0x5/0x1f jfs_get_block+0x661/0xa90 fs/jfs/inode.c:248 __block_write_begin_int+0x3b9/0x14b0 fs/buffer.c:1991 __block_write_begin fs/buffer.c:2041 [inline] block_write_begin+0xb5/0x440 fs/buffer.c:2102 jfs_write_begin+0x2d/0xd0 fs/jfs/inode.c:304 generic_perform_write+0x252/0x570 mm/filemap.c:3771 __generic_file_write_iter+0x2aa/0x4d0 mm/filemap.c:3899 generic_file_write_iter+0xdf/0x350 mm/filemap.c:3931 __kernel_write_iter+0x25e/0x730 fs/read_write.c:517 dump_emit_page fs/coredump.c:862 [inline] dump_user_range+0x244/0x680 fs/coredump.c:913 elf_core_dump+0x26de/0x3510 fs/binfmt_elf.c:2311 do_coredump+0x26ea/0x3c10 fs/coredump.c:760 get_signal+0x1be1/0x2430 kernel/signal.c:2844 arch_do_signal_or_restart+0x75/0x5b0 arch/x86/kernel/signal.c:306 exit_to_user_mode_loop kernel/entry/common.c:168 [inline] exit_to_user_mode_prepare+0x15f/0x250 kernel/entry/common.c:203 irqentry_exit_to_user_mode+0x5/0x30 kernel/entry/common.c:309 exc_page_fault+0xbc/0x170 arch/x86/mm/fault.c:1578 asm_exc_machine_check-0xe/0x40 RIP: 0033:0x73666a Code: Unable to access opcode bytes at 0x736640. RSP: 002b:0000000020000008 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f17833ac050 RCX: 00007f178328b5a9 RDX: 00000000200000c0 RSI: 0000000020000000 RDI: 0000000040000200 RBP: 00007f17832e67b0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 00007ffde099addf R14: 00007f1783fbe300 R15: 0000000000022000 ================================================================================