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 A9A6C248BA6; Wed, 15 Jan 2025 10:50:50 +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=1736938250; cv=none; b=smX6CPwndLDIYnva0Jji+UEq5lsyoUdQCTRvUVoYvRhoOFmE/RCLKQoyNcBW0DEs5MGxxnFbfTDnHGt3KiMUAl9MPGrsJwPFJjKlZffOc9Nxxofg/yOZfuA8KeL6o2VY0Cw92V1MfovV+2+terOqb6PBDKh0KmCRYfZzYtHC3vA= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1736938250; c=relaxed/simple; bh=/fhC0g/SSCzXgCh1qVuIgYyAAUdJFuXMgGRdSuPF9IQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=LIcqIcqAbjPExDlX2f4+kAbkAQizRWQcgezJHIvrl9KmNT4ZRTjDiRmGOIcHOgG/V+t7E0OR8dqYri8w+3MMy4sthpnU2vRtDSG+dzyXreZXuURHVWWyag4kaOP2aqOHsPVZZlG++Id5ukXXaP34gxuRYxyGShr801howcmkUDo= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=GGUgimF9; 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="GGUgimF9" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 23302C4CEDF; Wed, 15 Jan 2025 10:50:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1736938250; bh=/fhC0g/SSCzXgCh1qVuIgYyAAUdJFuXMgGRdSuPF9IQ=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=GGUgimF9fbdiZ77F3rCFsBd4P1E4TaNBxhKXQyfywQh2GZdWc3usrHbZplM5JTOpr avBXGDC3jK/5B6vVzxA2WZjWyBaAft0Z2VAaaKM9LIYmHPWYRNdrdDJpQKnZMUPF4h NXUJ4+Cf0DyYpKT76wIuCbXTqLhlBwf0L9S3I4aw= 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 6.12 097/189] sctp: sysctl: auth_enable: avoid using current->nsproxy Date: Wed, 15 Jan 2025 11:36:33 +0100 Message-ID: <20250115103610.189735615@linuxfoundation.org> X-Mailer: git-send-email 2.48.0 In-Reply-To: <20250115103606.357764746@linuxfoundation.org> References: <20250115103606.357764746@linuxfoundation.org> User-Agent: quilt/0.68 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Matthieu Baerts (NGI0) commit 15649fd5415eda664ef35780c2013adeb5d9c695 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, but that would increase the size of this fix, while 'sctp.ctl_sock' still needs to be retrieved from 'net' structure. Fixes: b14878ccb7fa ("net: sctp: cache auth_enable per endpoint") 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-v1-6-5df34b2083e8@kernel.org Signed-off-by: Jakub Kicinski Signed-off-by: Greg Kroah-Hartman --- net/sctp/sysctl.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/net/sctp/sysctl.c +++ b/net/sctp/sysctl.c @@ -499,7 +499,7 @@ static int proc_sctp_do_alpha_beta(const static int proc_sctp_do_auth(const 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.auth_enable); struct ctl_table tbl; int new_value, ret;