Hello, syzbot found the following issue on: HEAD commit: f7e6bd33d1d4 Merge branch 'bpf-support-new-insns-from-cpu-.. git tree: bpf-next console+strace: https://syzkaller.appspot.com/x/log.txt?x=114d3019a80000 kernel config: https://syzkaller.appspot.com/x/.config?x=8acaeb93ad7c6aaa dashboard link: https://syzkaller.appspot.com/bug?extid=3758842a6c01012aa73b compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15165dbea80000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=12259911a80000 Downloadable assets: disk image: https://storage.googleapis.com/syzbot-assets/f17904bb7ff9/disk-f7e6bd33.raw.xz vmlinux: https://storage.googleapis.com/syzbot-assets/8d3ac62bba3c/vmlinux-f7e6bd33.xz kernel image: https://storage.googleapis.com/syzbot-assets/62e7226b925f/bzImage-f7e6bd33.xz The issue was bisected to: commit f835bb6222998c8655bc4e85287d42b57c17b208 Author: Yonghong Song <yonghong.song@xxxxxxxxx> Date: Wed Jun 28 22:29:51 2023 +0000 bpf: Add kernel/bpftool asm support for new instructions bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=11fe5779a80000 final oops: https://syzkaller.appspot.com/x/report.txt?x=13fe5779a80000 console output: https://syzkaller.appspot.com/x/log.txt?x=15fe5779a80000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+3758842a6c01012aa73b@xxxxxxxxxxxxxxxxxxxxxxxxx Fixes: f835bb622299 ("bpf: Add kernel/bpftool asm support for new instructions") ================================================================================ UBSAN: array-index-out-of-bounds in kernel/bpf/disasm.c:192:38 index -1 is out of range for type 'char *[4]' CPU: 1 PID: 5026 Comm: syz-executor300 Not tainted 6.5.0-rc2-syzkaller-00599-gf7e6bd33d1d4 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2023 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x125/0x1b0 lib/dump_stack.c:106 ubsan_epilogue lib/ubsan.c:217 [inline] __ubsan_handle_out_of_bounds+0x111/0x150 lib/ubsan.c:348 print_bpf_insn+0x22d9/0x23c0 kernel/bpf/disasm.c:192 do_check kernel/bpf/verifier.c:16505 [inline] do_check_common+0x1402/0xd370 kernel/bpf/verifier.c:19061 do_check_main kernel/bpf/verifier.c:19124 [inline] bpf_check+0x8436/0xac50 kernel/bpf/verifier.c:19748 bpf_prog_load+0x153a/0x2270 kernel/bpf/syscall.c:2709 __sys_bpf+0xeed/0x4ec0 kernel/bpf/syscall.c:5345 __do_sys_bpf kernel/bpf/syscall.c:5449 [inline] __se_sys_bpf kernel/bpf/syscall.c:5447 [inline] __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5447 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f6f30a1b3a9 Code: 48 83 c4 28 c3 e8 37 17 00 00 0f 1f 80 00 00 00 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffee3c35308 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 00007ffee3c354e8 RCX: 00007f6f30a1b3a9 RDX: 0000000000000048 RSI: 0000000020000080 RDI: 0000000000000005 RBP: 00007f6f30a8e610 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000000001 R13: 00007ffee3c354d8 R14: 0000000000000001 R15: 0000000000000001 </TASK> ================================================================================ --- This report is generated by a bot. It may contain errors. See https://goo.gl/tpsmEJ for more information about syzbot. syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. syzbot will keep track of this issue. See: https://goo.gl/tpsmEJ#status for how to communicate with syzbot. For information about bisection process see: https://goo.gl/tpsmEJ#bisection If the bug is already fixed, let syzbot know by replying with: #syz fix: exact-commit-title If you want syzbot to run the reproducer, reply with: #syz test: git://repo/address.git branch-or-commit-hash If you attach or paste a git patch, syzbot will apply it before testing. If you want to change bug's subsystems, reply with: #syz set subsystems: new-subsystem (See the list of subsystem names on the web dashboard) If the bug is a duplicate of another bug, reply with: #syz dup: exact-subject-of-another-report If you want to undo deduplication, reply with: #syz undup
