From: syzbot <syzbot+4472ecce287501aa597a@syzkaller.appspotmail.com>
To: davem@davemloft.net, dsahern@kernel.org, edumazet@google.com,
horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org,
netdev@vger.kernel.org, pabeni@redhat.com,
syzkaller-bugs@googlegroups.com
Subject: [syzbot] [net?] KMSAN: uninit-value in __ipv6_dev_mc_dec (2)
Date: Fri, 09 May 2025 12:59:25 -0700 [thread overview]
Message-ID: <681e5e9d.050a0220.a19a9.013c.GAE@google.com> (raw)
Hello,
syzbot found the following issue on:
HEAD commit: 02ddfb981de8 Merge tag 'scsi-fixes' of git://git.kernel.or..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13a14670580000
kernel config: https://syzkaller.appspot.com/x/.config?x=9dc42c34a3f5c357
dashboard link: https://syzkaller.appspot.com/bug?extid=4472ecce287501aa597a
compiler: Debian clang version 20.1.2 (++20250402124445+58df0ef89dd6-1~exp1~20250402004600.97), Debian LLD 20.1.2
userspace arch: i386
Unfortunately, I don't have any reproducer for this issue yet.
Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/7dc8afe7520f/disk-02ddfb98.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/3194559250c2/vmlinux-02ddfb98.xz
kernel image: https://storage.googleapis.com/syzbot-assets/86c7c494f08f/bzImage-02ddfb98.xz
IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+4472ecce287501aa597a@syzkaller.appspotmail.com
=====================================================
BUG: KMSAN: uninit-value in __ipv6_dev_mc_dec+0x68a/0xd30 net/ipv6/mcast.c:1014
__ipv6_dev_mc_dec+0x68a/0xd30 net/ipv6/mcast.c:1014
addrconf_leave_solict net/ipv6/addrconf.c:2254 [inline]
__ipv6_ifa_notify+0xf97/0x1990 net/ipv6/addrconf.c:6299
addrconf_ifdown+0x1c61/0x32e0 net/ipv6/addrconf.c:3978
addrconf_notify+0x183/0x1d10 net/ipv6/addrconf.c:3777
notifier_call_chain kernel/notifier.c:85 [inline]
raw_notifier_call_chain+0xdd/0x410 kernel/notifier.c:453
call_netdevice_notifiers_info+0x1ac/0x2b0 net/core/dev.c:2176
call_netdevice_notifiers_extack net/core/dev.c:2214 [inline]
call_netdevice_notifiers net/core/dev.c:2228 [inline]
dev_close_many+0x52a/0x8f0 net/core/dev.c:1731
unregister_netdevice_many_notify+0x1106/0x4970 net/core/dev.c:11952
unregister_netdevice_many net/core/dev.c:12046 [inline]
unregister_netdevice_queue+0x3b1/0x600 net/core/dev.c:11889
unregister_netdevice include/linux/netdevice.h:3374 [inline]
__tun_detach+0x16c8/0x20c0 drivers/net/tun.c:620
tun_detach drivers/net/tun.c:636 [inline]
tun_chr_close+0xb7/0x290 drivers/net/tun.c:3390
__fput+0x608/0x1040 fs/file_table.c:465
____fput+0x25/0x30 fs/file_table.c:493
task_work_run+0x206/0x2b0 kernel/task_work.c:227
resume_user_mode_work+0x105/0x160 include/linux/resume_user_mode.h:50
exit_to_user_mode_loop kernel/entry/common.c:114 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:329 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x7b/0xb0 kernel/entry/common.c:218
__do_fast_syscall_32+0xbd/0x110 arch/x86/entry/syscall_32.c:309
do_fast_syscall_32+0x38/0x80 arch/x86/entry/syscall_32.c:331
do_SYSENTER_32+0x1f/0x30 arch/x86/entry/syscall_32.c:369
entry_SYSENTER_compat_after_hwframe+0x84/0x8e
Local variable maddr.i created at:
addrconf_leave_solict net/ipv6/addrconf.c:2248 [inline]
__ipv6_ifa_notify+0xe6f/0x1990 net/ipv6/addrconf.c:6299
addrconf_ifdown+0x1c61/0x32e0 net/ipv6/addrconf.c:3978
CPU: 1 UID: 0 PID: 10959 Comm: syz.4.717 Not tainted 6.15.0-rc3-syzkaller-00094-g02ddfb981de8 #0 PREEMPT(undef)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/29/2025
=====================================================
---
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reply other threads:[~2025-05-09 19:59 UTC|newest]
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