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 E8C9B248BB2; Wed, 15 Jan 2025 10:40:53 +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=1736937654; cv=none; b=LGaHJzAo6g6koW/AELgNO+1VQSvcqKiio/y/i7DmYrLrua2zE5Dgs5BmAIjD2Z1Re1Y3r3W9MJ5GUT0+98CFsewPHB84Ju6URaiBhM1NApUKm7gV9AR/GmJnnsP7Bs2aPO2dUiXFITLZ+fRk9cHprJ+8fIACBjUSSWX3wEw+2Q0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736937654; c=relaxed/simple; bh=mlgLev/IVSTeh8D4AOxxrsutLvUcDP35a7cbK+hyFDw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ACuFBaaqYXiqXrx9dpfR7ivljIPrtNtiFRs1+SNAJAIeUQiB9g3rmhI3cxLsN8D83scMaEBfz+hf2j/B1eadWnXJO9gbpvewxiBETGs/vrqiEACbfbnvF4xEx0qT7QqyEExiOVFPbeo4tsXTuefkrt9QXshpwpATeAlJPSlGpME= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=d0JOC78j; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="d0JOC78j" Received: by smtp.kernel.org (Postfix) with ESMTPSA id E0C5AC4CEE1; Wed, 15 Jan 2025 10:40:52 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1736937653; bh=mlgLev/IVSTeh8D4AOxxrsutLvUcDP35a7cbK+hyFDw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=d0JOC78jfJ7THJAl9xQ7xLWPZMmRh13CW0NPFQTBfnu2Fda7RxOj53wWx7pHiZSOC /W4vDN/ATaR/xaUUTHtYVoXiNIvTmdv88jajDAPXbGBfaLXGwln19XEsqYFolB3FNu C9KXsIe/jrqdoMCSANg5rFKmjIXWFYKqz+exeFoY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Al Viro , "Matthieu Baerts (NGI0)" , Jakub Kicinski Subject: [PATCH 6.1 42/92] sctp: sysctl: plpmtud_probe_interval: avoid using current->nsproxy Date: Wed, 15 Jan 2025 11:37:00 +0100 Message-ID: <20250115103549.210778501@linuxfoundation.org> X-Mailer: git-send-email 2.48.0 In-Reply-To: <20250115103547.522503305@linuxfoundation.org> References: <20250115103547.522503305@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ From: Matthieu Baerts (NGI0) commit 6259d2484d0ceff42245d1f09cc8cb6ee72d847a upstream. As mentioned in a previous commit of this series, using the 'net' structure via 'current' is not recommended for different reasons: - Inconsistency: getting info from the reader's/writer's netns vs only from the opener's netns. - current->nsproxy can be NULL in some cases, resulting in an 'Oops' (null-ptr-deref), e.g. when the current task is exiting, as spotted by syzbot [1] using acct(2). The 'net' structure can be obtained from the table->data using container_of(). Note that table->data could also be used directly, as this is the only member needed from the 'net' structure, but that would increase the size of this fix, to use '*data' everywhere 'net->sctp.probe_interval' is used. Fixes: d1e462a7a5f3 ("sctp: add probe_interval in sysctl and sock/asoc/transport") Cc: stable@vger.kernel.org Link: https://lore.kernel.org/67769ecb.050a0220.3a8527.003f.GAE@google.com [1] Suggested-by: Al Viro Signed-off-by: Matthieu Baerts (NGI0) Link: https://patch.msgid.link/20250108-net-sysctl-current-nsproxy-v1-8-5df34b2083e8@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/sctp/sysctl.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/net/sctp/sysctl.c +++ b/net/sctp/sysctl.c @@ -562,7 +562,8 @@ static int proc_sctp_do_udp_port(struct static int proc_sctp_do_probe_interval(struct ctl_table *ctl, int write, void *buffer, size_t *lenp, loff_t *ppos) { - struct net *net = current->nsproxy->net_ns; + struct net *net = container_of(ctl->data, struct net, + sctp.probe_interval); struct ctl_table tbl; int ret, new_value;