All of lore.kernel.org
 help / color / mirror / Atom feed
From: syzbot <syzbot+853242d9c9917165d791@syzkaller.appspotmail.com>
To: andrii@kernel.org, ast@kernel.org, bpf@vger.kernel.org,
	 daniel@iogearbox.net, haoluo@google.com,
	john.fastabend@gmail.com,  jolsa@kernel.org, kpsingh@kernel.org,
	linux-kernel@vger.kernel.org,  martin.lau@linux.dev,
	sdf@google.com, song@kernel.org,
	 syzkaller-bugs@googlegroups.com, yonghong.song@linux.dev
Subject: Re: [syzbot] [bpf?] KMSAN: uninit-value in ___bpf_prog_run (4)
Date: Sun, 21 Jan 2024 23:46:19 -0800	[thread overview]
Message-ID: <000000000000893270060f840665@google.com> (raw)
In-Reply-To: <000000000000dea025060d6bc3bc@google.com>

syzbot has found a reproducer for the following issue on:

HEAD commit:    9f8413c4a66f Merge tag 'cgroup-for-6.8' of git://git.kerne..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=1493fa3de80000
kernel config:  https://syzkaller.appspot.com/x/.config?x=656820e61b758b15
dashboard link: https://syzkaller.appspot.com/bug?extid=853242d9c9917165d791
compiler:       Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro:      https://syzkaller.appspot.com/x/repro.syz?x=139d21e7e80000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=12d6066fe80000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/79d9f2f4b065/disk-9f8413c4.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/cbc68430d9c6/vmlinux-9f8413c4.xz
kernel image: https://storage.googleapis.com/syzbot-assets/9740ad9fc172/bzImage-9f8413c4.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+853242d9c9917165d791@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in ___bpf_prog_run+0xa766/0xdb80 kernel/bpf/core.c:2037
 ___bpf_prog_run+0xa766/0xdb80 kernel/bpf/core.c:2037
 __bpf_prog_run512+0xb5/0xe0 kernel/bpf/core.c:2203
 bpf_dispatcher_nop_func include/linux/bpf.h:1196 [inline]
 __bpf_prog_run include/linux/filter.h:651 [inline]
 bpf_prog_run include/linux/filter.h:658 [inline]
 bpf_test_run+0x482/0xb00 net/bpf/test_run.c:423
 bpf_prog_test_run_skb+0x14e5/0x1f20 net/bpf/test_run.c:1045
 bpf_prog_test_run+0x6af/0xac0 kernel/bpf/syscall.c:4040
 __sys_bpf+0x649/0xd60 kernel/bpf/syscall.c:5401
 __do_sys_bpf kernel/bpf/syscall.c:5487 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5485 [inline]
 __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5485
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x6d/0x140 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was stored to memory at:
 ___bpf_prog_run+0x8567/0xdb80
 __bpf_prog_run512+0xb5/0xe0 kernel/bpf/core.c:2203
 bpf_dispatcher_nop_func include/linux/bpf.h:1196 [inline]
 __bpf_prog_run include/linux/filter.h:651 [inline]
 bpf_prog_run include/linux/filter.h:658 [inline]
 bpf_test_run+0x482/0xb00 net/bpf/test_run.c:423
 bpf_prog_test_run_skb+0x14e5/0x1f20 net/bpf/test_run.c:1045
 bpf_prog_test_run+0x6af/0xac0 kernel/bpf/syscall.c:4040
 __sys_bpf+0x649/0xd60 kernel/bpf/syscall.c:5401
 __do_sys_bpf kernel/bpf/syscall.c:5487 [inline]
 __se_sys_bpf kernel/bpf/syscall.c:5485 [inline]
 __x64_sys_bpf+0xa0/0xe0 kernel/bpf/syscall.c:5485
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0x6d/0x140 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Local variable stack created at:
 __bpf_prog_run512+0x45/0xe0 kernel/bpf/core.c:2203
 bpf_dispatcher_nop_func include/linux/bpf.h:1196 [inline]
 __bpf_prog_run include/linux/filter.h:651 [inline]
 bpf_prog_run include/linux/filter.h:658 [inline]
 bpf_test_run+0x482/0xb00 net/bpf/test_run.c:423

CPU: 0 PID: 5010 Comm: syz-executor315 Not tainted 6.7.0-syzkaller-00562-g9f8413c4a66f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023
=====================================================


---
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.

      reply	other threads:[~2024-01-22  7:46 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-12-26 15:59 [syzbot] [bpf?] KMSAN: uninit-value in ___bpf_prog_run (4) syzbot
2024-01-22  7:46 ` syzbot [this message]

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=000000000000893270060f840665@google.com \
    --to=syzbot+853242d9c9917165d791@syzkaller.appspotmail.com \
    --cc=andrii@kernel.org \
    --cc=ast@kernel.org \
    --cc=bpf@vger.kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=haoluo@google.com \
    --cc=john.fastabend@gmail.com \
    --cc=jolsa@kernel.org \
    --cc=kpsingh@kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=martin.lau@linux.dev \
    --cc=sdf@google.com \
    --cc=song@kernel.org \
    --cc=syzkaller-bugs@googlegroups.com \
    --cc=yonghong.song@linux.dev \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.