[syzbot] [bpf?] UBSAN: array-index-out-of-bounds in bpf_prog_select_runtime

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit:    9187210eee7d Merge tag 'net-next-6.9' of git://git.kernel...
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1736a3da180000
kernel config:  https://syzkaller.appspot.com/x/.config?x=222448ff79dba2ea
dashboard link: https://syzkaller.appspot.com/bug?extid=d2a2c639d03ac200a4f1
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=16b3fdc1180000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=11201969180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/98c1ea7ddb95/disk-9187210e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/343c5524f68f/vmlinux-9187210e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/6c0c68b0ee90/bzImage-9187210e.xz

The issue was bisected to:

commit 011832b97b311bb9e3c27945bc0d1089a14209c9
Author: Alexei Starovoitov <ast@xxxxxxxxxx>
Date:   Wed Mar 6 03:19:26 2024 +0000

    bpf: Introduce may_goto instruction

bisection log:  https://syzkaller.appspot.com/x/bisect.txt?x=115e578e180000
final oops:     https://syzkaller.appspot.com/x/report.txt?x=135e578e180000
console output: https://syzkaller.appspot.com/x/log.txt?x=155e578e180000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+d2a2c639d03ac200a4f1@xxxxxxxxxxxxxxxxxxxxxxxxx
Fixes: 011832b97b31 ("bpf: Introduce may_goto instruction")

------------[ cut here ]------------
UBSAN: array-index-out-of-bounds in kernel/bpf/core.c:2349:29
index 16 is out of range for type '<unknown> *[16]'
CPU: 1 PID: 5060 Comm: syz-executor255 Not tainted 6.8.0-syzkaller-05202-g9187210eee7d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
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+0x110/0x150 lib/ubsan.c:415
 bpf_prog_select_func kernel/bpf/core.c:2349 [inline]
 bpf_prog_select_runtime+0x5aa/0x640 kernel/bpf/core.c:2380
 bpf_prog_load+0xf0f/0x2660 kernel/bpf/syscall.c:2899
 __sys_bpf+0x9b4/0x4b40 kernel/bpf/syscall.c:5631
 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5736 [inline]
 __x64_sys_bpf+0x78/0xc0 kernel/bpf/syscall.c:5736
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xd2/0x260 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7fa2a0fe73e9
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:00007ffdd829a698 EFLAGS: 00000246 ORIG_RAX: 0000000000000141
RAX: ffffffffffffffda RBX: 00007ffdd829a878 RCX: 00007fa2a0fe73e9
RDX: 0000000000000048 RSI: 00000000200017c0 RDI: 0000000000000005
RBP: 00007fa2a105a610 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 0000000000000001
R13: 00007ffdd829a868 R14: 0000000000000001 R15: 0000000000000001
 </TASK>
---[ end trace ]---


---
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