From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9BD7182D98; Mon, 6 Jan 2025 14:27:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736173673; cv=none; b=sJNMMuv+/p3Ji2f6V7WreXsn7JdhFYJ1x2sZNV00MmhMsPdI49SU5QjESqci4QX3SNjrDPa2kNoWkknZqWNc1IqS7LKh5C9zIr2sRJCtNXX9KJmK6RPoaWfh1M0w/zVq2lNhd5h2tslWPa9wTJ6lIltKbBxOxtfu9RUohYN76VA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736173673; c=relaxed/simple; bh=HF9s2Rd1qqE2IHqKIMFnrzcy1PTMTigjAI80Xa4+BF0=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=lzF5kT8ZIWaIl39d0bjewgoYdBK6wNUoZAXLLXfJTa67NPp5t9+VogLZ518jEJi28YLOdK1eD9cPJbMsRzRSa17228WO3Yh24GARzD3Gg+DKkumsIzRKSjjpZV5BB6/t6yqW1QajRtS677t9pHTSNi5IpESV3ALjujlkrh5KXAw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=SOdbxTf7; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="SOdbxTf7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 33345C4CED2; Mon, 6 Jan 2025 14:27:48 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1736173673; bh=HF9s2Rd1qqE2IHqKIMFnrzcy1PTMTigjAI80Xa4+BF0=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=SOdbxTf7ceC3djrDiD6f1qlFcv/neeWlM5Ees8d4E9RNuke7w9guqO/ZYjN1t++Ed hORFvuMDzJGBKHqp5pZ49GfvEWmhd/XqXL9savqsbbPtt7w4z040QdNUGkf+eGH6ZN MA6wwVbeC2/4/2QTWyrVyRIjqF6usUMZq9zctqI2wZdINorvob3FxTuwYOZUWRwVOg Mam+WYUxcGyH6V5Mm4sj1gROTeH3jWydPcs0IxQhyERdUaPiQEtqdl87gSjyJn+uWW oejdWyFvg5dhvWhhlSzQdTThPkS68KufW2NNwUZO6xELmC75mUhxh1s2uLTOx6ISro V/1DSWuPGD+Wg== Message-ID: <2b0bcf38-5408-4268-bb69-cbea2b250521@kernel.org> Date: Mon, 6 Jan 2025 15:27:47 +0100 Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Beta Subject: Re: [syzbot] [mptcp?] general protection fault in proc_scheduler Content-Language: en-GB To: Joel Granados , Eric Dumazet , Al Viro Cc: davem@davemloft.net, geliang@kernel.org, horms@kernel.org, kuba@kernel.org, linux-kernel@vger.kernel.org, martineau@kernel.org, mptcp@lists.linux.dev, netdev@vger.kernel.org, pabeni@redhat.com, syzkaller-bugs@googlegroups.com, syzbot References: <67769ecb.050a0220.3a8527.003f.GAE@google.com> <7927eae8-4d26-4340-852a-b93fcf1eba89@kernel.org> From: Matthieu Baerts Autocrypt: addr=matttbe@kernel.org; keydata= xsFNBFXj+ekBEADxVr99p2guPcqHFeI/JcFxls6KibzyZD5TQTyfuYlzEp7C7A9swoK5iCvf YBNdx5Xl74NLSgx6y/1NiMQGuKeu+2BmtnkiGxBNanfXcnl4L4Lzz+iXBvvbtCbynnnqDDqU c7SPFMpMesgpcu1xFt0F6bcxE+0ojRtSCZ5HDElKlHJNYtD1uwY4UYVGWUGCF/+cY1YLmtfb WdNb/SFo+Mp0HItfBC12qtDIXYvbfNUGVnA5jXeWMEyYhSNktLnpDL2gBUCsdbkov5VjiOX7 CRTkX0UgNWRjyFZwThaZADEvAOo12M5uSBk7h07yJ97gqvBtcx45IsJwfUJE4hy8qZqsA62A nTRflBvp647IXAiCcwWsEgE5AXKwA3aL6dcpVR17JXJ6nwHHnslVi8WesiqzUI9sbO/hXeXw TDSB+YhErbNOxvHqCzZEnGAAFf6ges26fRVyuU119AzO40sjdLV0l6LE7GshddyazWZf0iac nEhX9NKxGnuhMu5SXmo2poIQttJuYAvTVUNwQVEx/0yY5xmiuyqvXa+XT7NKJkOZSiAPlNt6 VffjgOP62S7M9wDShUghN3F7CPOrrRsOHWO/l6I/qJdUMW+MHSFYPfYiFXoLUZyPvNVCYSgs 3oQaFhHapq1f345XBtfG3fOYp1K2wTXd4ThFraTLl8PHxCn4ywARAQABzSRNYXR0aGlldSBC YWVydHMgPG1hdHR0YmVAa2VybmVsLm9yZz7CwZEEEwEIADsCGwMFCwkIBwIGFQoJCAsCBBYC AwECHgECF4AWIQToy4X3aHcFem4n93r2t4JPQmmgcwUCZUDpDAIZAQAKCRD2t4JPQmmgcz33 EACjROM3nj9FGclR5AlyPUbAq/txEX7E0EFQCDtdLPrjBcLAoaYJIQUV8IDCcPjZMJy2ADp7 /zSwYba2rE2C9vRgjXZJNt21mySvKnnkPbNQGkNRl3TZAinO1Ddq3fp2c/GmYaW1NWFSfOmw MvB5CJaN0UK5l0/drnaA6Hxsu62V5UnpvxWgexqDuo0wfpEeP1PEqMNzyiVPvJ8bJxgM8qoC cpXLp1Rq/jq7pbUycY8GeYw2j+FVZJHlhL0w0Zm9CFHThHxRAm1tsIPc+oTorx7haXP+nN0J iqBXVAxLK2KxrHtMygim50xk2QpUotWYfZpRRv8dMygEPIB3f1Vi5JMwP4M47NZNdpqVkHrm jvcNuLfDgf/vqUvuXs2eA2/BkIHcOuAAbsvreX1WX1rTHmx5ud3OhsWQQRVL2rt+0p1DpROI 3Ob8F78W5rKr4HYvjX2Inpy3WahAm7FzUY184OyfPO/2zadKCqg8n01mWA9PXxs84bFEV2mP VzC5j6K8U3RNA6cb9bpE5bzXut6T2gxj6j+7TsgMQFhbyH/tZgpDjWvAiPZHb3sV29t8XaOF BwzqiI2AEkiWMySiHwCCMsIH9WUH7r7vpwROko89Tk+InpEbiphPjd7qAkyJ+tNIEWd1+MlX ZPtOaFLVHhLQ3PLFLkrU3+Yi3tXqpvLE3gO3LM7BTQRV4/npARAA5+u/Sx1n9anIqcgHpA7l 5SUCP1e/qF7n5DK8LiM10gYglgY0XHOBi0S7vHppH8hrtpizx+7t5DBdPJgVtR6SilyK0/mp 9nWHDhc9rwU3KmHYgFFsnX58eEmZxz2qsIY8juFor5r7kpcM5dRR9aB+HjlOOJJgyDxcJTwM 1ey4L/79P72wuXRhMibN14SX6TZzf+/XIOrM6TsULVJEIv1+NdczQbs6pBTpEK/G2apME7vf mjTsZU26Ezn+LDMX16lHTmIJi7Hlh7eifCGGM+g/AlDV6aWKFS+sBbwy+YoS0Zc3Yz8zrdbi Kzn3kbKd+99//mysSVsHaekQYyVvO0KD2KPKBs1S/ImrBb6XecqxGy/y/3HWHdngGEY2v2IP Qox7mAPznyKyXEfG+0rrVseZSEssKmY01IsgwwbmN9ZcqUKYNhjv67WMX7tNwiVbSrGLZoqf Xlgw4aAdnIMQyTW8nE6hH/Iwqay4S2str4HZtWwyWLitk7N+e+vxuK5qto4AxtB7VdimvKUs x6kQO5F3YWcC3vCXCgPwyV8133+fIR2L81R1L1q3swaEuh95vWj6iskxeNWSTyFAVKYYVskG V+OTtB71P1XCnb6AJCW9cKpC25+zxQqD2Zy0dK3u2RuKErajKBa/YWzuSaKAOkneFxG3LJIv Hl7iqPF+JDCjB5sAEQEAAcLBXwQYAQIACQUCVeP56QIbDAAKCRD2t4JPQmmgc5VnD/9YgbCr HR1FbMbm7td54UrYvZV/i7m3dIQNXK2e+Cbv5PXf19ce3XluaE+wA8D+vnIW5mbAAiojt3Mb 6p0WJS3QzbObzHNgAp3zy/L4lXwc6WW5vnpWAzqXFHP8D9PTpqvBALbXqL06smP47JqbyQxj Xf7D2rrPeIqbYmVY9da1KzMOVf3gReazYa89zZSdVkMojfWsbq05zwYU+SCWS3NiyF6QghbW voxbFwX1i/0xRwJiX9NNbRj1huVKQuS4W7rbWA87TrVQPXUAdkyd7FRYICNW+0gddysIwPoa KrLfx3Ba6Rpx0JznbrVOtXlihjl4KV8mtOPjYDY9u+8x412xXnlGl6AC4HLu2F3ECkamY4G6 UxejX+E6vW6Xe4n7H+rEX5UFgPRdYkS1TA/X3nMen9bouxNsvIJv7C6adZmMHqu/2azX7S7I vrxxySzOw9GxjoVTuzWMKWpDGP8n71IFeOot8JuPZtJ8omz+DZel+WCNZMVdVNLPOd5frqOv mpz0VhFAlNTjU1Vy0CnuxX3AM51J8dpdNyG0S8rADh6C8AKCDOfUstpq28/6oTaQv7QZdge0 JY6dglzGKnCi/zsmp2+1w559frz4+IC7j/igvJGX4KDDKUs0mlld8J2u2sBXv7CGxdzQoHaz lzVbFe7fduHbABmYz9cefQpO7wDE/Q== Organization: NGI0 Core In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Hi Joel, Eric, Al, On 06/01/2025 14:32, Joel Granados wrote: > On Sat, Jan 04, 2025 at 08:11:52PM +0100, Matthieu Baerts wrote: >> Hi Eric, >> >> (+cc Joel) >> >> Thank you for your reply! >> >> On 04/01/2025 19:53, Eric Dumazet wrote: >>> On Sat, Jan 4, 2025 at 7:38 PM Matthieu Baerts wrote: >>>> >>>> Hi Eric, >>>> >>>> Thank you for the bug report! >>>> >>>> On 02/01/2025 16:21, Eric Dumazet wrote: >>>>> On Thu, Jan 2, 2025 at 3:12 PM syzbot >>>>> wrote: >>>>>> >>>>>> Hello, >>>>>> >>>>>> syzbot found the following issue on: >>>>>> >>>>>> HEAD commit: ccb98ccef0e5 Merge tag 'platform-drivers-x86-v6.13-4' of g.. >>>>>> git tree: upstream >>>>>> console output: https://syzkaller.appspot.com/x/log.txt?x=128f6ac4580000 >>>>>> kernel config: https://syzkaller.appspot.com/x/.config?x=86dd15278dbfe19f >>>>>> dashboard link: https://syzkaller.appspot.com/bug?extid=e364f774c6f57f2c86d1 >>>>>> 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=1245eaf8580000 >>>>>> >>>>>> Downloadable assets: >>>>>> disk image: https://storage.googleapis.com/syzbot-assets/d24eb225cff7/disk-ccb98cce.raw.xz >>>>>> vmlinux: https://storage.googleapis.com/syzbot-assets/dd81532f8240/vmlinux-ccb98cce.xz >>>>>> kernel image: https://storage.googleapis.com/syzbot-assets/18b08e4bbf40/bzImage-ccb98cce.xz >>>>>> >>>>>> IMPORTANT: if you fix the issue, please add the following tag to the commit: >>>>>> Reported-by: syzbot+e364f774c6f57f2c86d1@syzkaller.appspotmail.com >>>>>> >>>>>> Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN PTI >>>>>> KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] >>>>>> CPU: 1 UID: 0 PID: 5924 Comm: syz-executor Not tainted 6.13.0-rc5-syzkaller-00004-gccb98ccef0e5 #0 >>>>>> Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024 >>>>>> RIP: 0010:proc_scheduler+0xc6/0x3c0 net/mptcp/ctrl.c:125 >>>>>> Code: 03 42 80 3c 38 00 0f 85 fe 02 00 00 4d 8b a4 24 08 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7c 24 28 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 cc 02 00 00 4d 8b 7c 24 28 48 8d 84 24 c8 00 00 >>>>>> RSP: 0018:ffffc900034774e8 EFLAGS: 00010206 >>>>>> >>>>>> RAX: dffffc0000000000 RBX: 1ffff9200068ee9e RCX: ffffc90003477620 >>>>>> RDX: 0000000000000005 RSI: ffffffff8b08f91e RDI: 0000000000000028 >>>>>> RBP: 0000000000000001 R08: ffffc90003477710 R09: 0000000000000040 >>>>>> R10: 0000000000000040 R11: 00000000726f7475 R12: 0000000000000000 >>>>>> R13: ffffc90003477620 R14: ffffc90003477710 R15: dffffc0000000000 >>>>>> FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 >>>>>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >>>>>> CR2: 00007fee3cd452d8 CR3: 000000007d116000 CR4: 00000000003526f0 >>>>>> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >>>>>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 >>>>>> Call Trace: >>>>>> >>>>>> proc_sys_call_handler+0x403/0x5d0 fs/proc/proc_sysctl.c:601 >>>>>> __kernel_write_iter+0x318/0xa80 fs/read_write.c:612 >>>>>> __kernel_write+0xf6/0x140 fs/read_write.c:632 >>>>>> do_acct_process+0xcb0/0x14a0 kernel/acct.c:539 >>>>>> acct_pin_kill+0x2d/0x100 kernel/acct.c:192 >>>>>> pin_kill+0x194/0x7c0 fs/fs_pin.c:44 >>>>>> mnt_pin_kill+0x61/0x1e0 fs/fs_pin.c:81 >>>>>> cleanup_mnt+0x3ac/0x450 fs/namespace.c:1366 >>>>>> task_work_run+0x14e/0x250 kernel/task_work.c:239 >>>>>> exit_task_work include/linux/task_work.h:43 [inline] >>>>>> do_exit+0xad8/0x2d70 kernel/exit.c:938 >>>>>> do_group_exit+0xd3/0x2a0 kernel/exit.c:1087 >>>>>> get_signal+0x2576/0x2610 kernel/signal.c:3017 >>>>>> arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337 >>>>>> exit_to_user_mode_loop kernel/entry/common.c:111 [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+0x150/0x2a0 kernel/entry/common.c:218 >>>>>> do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89 >>>>>> entry_SYSCALL_64_after_hwframe+0x77/0x7f >>>>>> RIP: 0033:0x7fee3cb87a6a >>>>>> Code: Unable to access opcode bytes at 0x7fee3cb87a40. >>>>>> RSP: 002b:00007fffcccac688 EFLAGS: 00000202 ORIG_RAX: 0000000000000037 >>>>>> RAX: 0000000000000000 RBX: 00007fffcccac710 RCX: 00007fee3cb87a6a >>>>>> RDX: 0000000000000041 RSI: 0000000000000000 RDI: 0000000000000003 >>>>>> RBP: 0000000000000003 R08: 00007fffcccac6ac R09: 00007fffcccacac7 >>>>>> R10: 00007fffcccac710 R11: 0000000000000202 R12: 00007fee3cd49500 >>>>>> R13: 00007fffcccac6ac R14: 0000000000000000 R15: 00007fee3cd4b000 >>>>>> >>>>>> Modules linked in: >>>>>> ---[ end trace 0000000000000000 ]--- >>>>>> RIP: 0010:proc_scheduler+0xc6/0x3c0 net/mptcp/ctrl.c:125 >>>>>> Code: 03 42 80 3c 38 00 0f 85 fe 02 00 00 4d 8b a4 24 08 09 00 00 48 b8 00 00 00 00 00 fc ff df 49 8d 7c 24 28 48 89 fa 48 c1 ea 03 <80> 3c 02 00 0f 85 cc 02 00 00 4d 8b 7c 24 28 48 8d 84 24 c8 00 00 >>>>>> RSP: 0018:ffffc900034774e8 EFLAGS: 00010206 >>>>>> RAX: dffffc0000000000 RBX: 1ffff9200068ee9e RCX: ffffc90003477620 >>>>>> RDX: 0000000000000005 RSI: ffffffff8b08f91e RDI: 0000000000000028 >>>>>> RBP: 0000000000000001 R08: ffffc90003477710 R09: 0000000000000040 >>>>>> R10: 0000000000000040 R11: 00000000726f7475 R12: 0000000000000000 >>>>>> R13: ffffc90003477620 R14: ffffc90003477710 R15: dffffc0000000000 >>>>>> FS: 0000000000000000(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 >>>>>> CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 >>>>>> CR2: 00007fee3cd452d8 CR3: 000000007d116000 CR4: 00000000003526f0 >>>>>> DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 >>>>>> DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 >>>>>> ---------------- >>>>>> Code disassembly (best guess), 1 bytes skipped: >>>>>> 0: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) >>>>>> 5: 0f 85 fe 02 00 00 jne 0x309 >>>>>> b: 4d 8b a4 24 08 09 00 mov 0x908(%r12),%r12 >>>>>> 12: 00 >>>>>> 13: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax >>>>>> 1a: fc ff df >>>>>> 1d: 49 8d 7c 24 28 lea 0x28(%r12),%rdi >>>>>> 22: 48 89 fa mov %rdi,%rdx >>>>>> 25: 48 c1 ea 03 shr $0x3,%rdx >>>>>> * 29: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction >>>>>> 2d: 0f 85 cc 02 00 00 jne 0x2ff >>>>>> 33: 4d 8b 7c 24 28 mov 0x28(%r12),%r15 >>>>>> 38: 48 rex.W >>>>>> 39: 8d .byte 0x8d >>>>>> 3a: 84 24 c8 test %ah,(%rax,%rcx,8) >>>> >>>> (...) >>>> >>>>> I thought acct(2) was only allowing regular files. >>>>> >>>>> acct_on() indeed has : >>>>> >>>>> if (!S_ISREG(file_inode(file)->i_mode)) { >>>>> kfree(acct); >>>>> filp_close(file, NULL); >>>>> return -EACCES; >>>>> } >>>>> >>>>> It seems there are other ways to call do_acct_process() targeting a sysfs file ? > If this is the case, can you point me to the place where this happens? > >>>> >>>> Just to be sure I'm not misunderstanding your comment: do you mean that >>>> here, the issue is *not* in MPTCP code where we get the 'struct net' >>>> pointer via 'current->nsproxy->net_ns', but in the FS part, right? >>>> >>>> Here, we have an issue because 'current->nsproxy' is NULL, but is it >>>> normal? Or should we simply exit with an error if it is the case because >>>> we are in an exiting phase? >>>> >>>> I'm just a bit confused, because it looks like 'net' is retrieved from >>>> different places elsewhere when dealing with sysfs: some get it from >>>> 'current' like us, some assign 'net' to 'table->extra2', others get it >>>> from 'table->data' (via a container_of()), etc. Maybe we should not use >>>> 'current->nsproxy->net_ns' here then? >>> >>> I do think this is a bug in process accounting, not in networking. >>> >>> It might make sense to output a record on a regular file, but probably >>> not on any other files. > It for sure does not make sense to output a record on a sysctl file that > has a maxlen of just 3*sizeof(int) (kernel/acct.c:79). > >>> >>> diff --git a/kernel/acct.c b/kernel/acct.c >>> index 179848ad33e978a557ce695a0d6020aa169177c6..a211305cb930f6860d02de7f45ebd260ae03a604 >>> 100644 >>> --- a/kernel/acct.c >>> +++ b/kernel/acct.c >>> @@ -495,6 +495,9 @@ static void do_acct_process(struct bsd_acct_struct *acct) >>> const struct cred *orig_cred; >>> struct file *file = acct->file; >>> >>> + if (S_ISREG(file_inode(file)->i_mode)) >>> + return; >>> + > This seems like it does not handle the actual culprit which is. Why is > the sysctl file being used for the accounting. > >>> /* >>> * Accounting records are not subject to resource limits. >>> */ >> >> OK, thank you, that's clearer. >> >> So this is then more a question for Joel, right? >> >> Do you plan to send this patch to him? >> >> #syz set subsystems: fs >> >> Cheers, >> Matt >> -- >> Sponsored by the NGI0 Core fund. >> > > So what is happening is that: > 1. The accounting file is set to a non-sysctl file. > 2. And when accounting tries to write to this file, you get the > behaviour explained in this mail? > > Please correct me if I have miss-read the situation. @Joel: Thank you for your reply! I'm sorry, I'm not sure whether I can help here. I hope Eric and/or Al can jump in. What I can say is that the original issue has been found by syzbot, and the reproducer [1] shows that 3 syscalls have been used: - openat('/proc/sys/net/mptcp/scheduler') - mprotect() - acct() Please also note that the conversation continued in a sub-tread where you are not in the Cc list, see [2]. In short, Eric suggested another patch only for sysfs, and Al recommended dropping the use of 'current->nsproxy'. On my side, I'm looking at dropping the use of 'current->nsproxy' in sysctl callbacks. I guess such patches will be seen as fixes, except if Eric's new patch is enough for stable? [1] https://syzkaller.appspot.com/x/repro.syz?x=1245eaf8580000 [2] https://lore.kernel.org/netdev/67769ecb.050a0220.3a8527.003f.GAE@google.com/T/#m862d0913ebfcec5e462a9c33b47bc3f6440a2900 Cheers, Matt -- Sponsored by the NGI0 Core fund.