================================================================================ UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dtree.c:3385:20 index -1 is out of range for type 'struct dtslot[128]' CPU: 1 PID: 6503 Comm: syz-executor.4 Not tainted 5.15.158-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call trace: dump_backtrace+0x0/0x530 arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x108/0x170 lib/dump_stack.c:106 dump_stack+0x1c/0x58 lib/dump_stack.c:113 ubsan_epilogue lib/ubsan.c:151 [inline] __ubsan_handle_out_of_bounds+0x108/0x15c lib/ubsan.c:282 dtReadFirst+0x4bc/0x9bc fs/jfs/jfs_dtree.c:3385 jfs_readdir+0x6f0/0x385c fs/jfs/jfs_dtree.c:3116 iterate_dir+0x1f4/0x4e4 __do_sys_getdents64 fs/readdir.c:369 [inline] __se_sys_getdents64 fs/readdir.c:354 [inline] __arm64_sys_getdents64+0x1c4/0x4c4 fs/readdir.c:354 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x7c/0x1f0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0x84/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 ================================================================================ ERROR: (device loop4): dtReadFirst: btstack overrun ERROR: (device loop4): remounting filesystem as read-only btstack dump: bn = 0, index = 0 bn = 0, index = 0 bn = 0, index = 0 bn = 0, index = 0 bn = 0, index = 0 bn = 0, index = 0 bn = 0, index = 0 bn = 0, index = 0