From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 D9A28341ABB for ; Thu, 23 Jul 2026 19:59:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784836756; cv=none; b=no/Tg1M9MRv6+3aSf3lHtaf2ficF76pt27BsJYceUygkdplDpGraJpkwhZ6PN66NgMJlw/yO67drU27g1avD9lkh/j/UwBUNWs6fdjbor/ntEbCm6tHDUstyRT8Q+bkyoQ6kpHd+4l9L47lU1H2kjACy9+1cbaEVqyyvEBPQyRQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784836756; c=relaxed/simple; bh=VxZwcSb1QdN4wsKx6LrWqTy7RWNSYmgjBYXHG2aYwf4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=tXP7Rue0MbAIs+mO/9T8mzYdFcv8oOuDf3BLwmc1i113c76cS2z+5dNViapJ2Pl2CD6cxF0OZA/OpNK8CGu1QAhWAvBOkTqOAFDTPgj7U1epVnfQFjUJqMKlNpwq9cyB3kx9IKbotrzWP4U8x75xSwyhihudQ94m5DbHGnl14HA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=mCNRmq2Z; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="mCNRmq2Z" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 0C9291F000E9; Thu, 23 Jul 2026 19:59:13 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1784836754; bh=fKfnLzsInL2+Vl2vPv3O2SGuIl0Ho6Lt8OXBH9C8PxM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=mCNRmq2ZkGwOyPbpRgqpuZpzYan+zJxHg4hMTzx9KeNjlXQCeuv32MuefNv1iuEZ8 nqBjCtxk01+zCfN1f9LEmVEV2ieaBUapChIkajhyn/IMvjz0hLxh8VnS4dgdGuhsHZ bFqDqZGEv1Zs9kBu+3SocyUjpN4+ZPUSw5QSDU3eLkEO6q9Mm3NUDOO+vcDqGFWDsf DTu/J8Wwgn/dRv5M1IywnaBQkQmXu46MKmPFbGBxzlSZzjoR8tWD5zT4JddHyaFlz3 RZuT5/WIOOZEBUbAzEA7pLhzZwNj6vk9tAPIwrc0gS1vaoxybNv/ZDTW1n7G+vhxyN FsHQ7OAWyE9BA== From: Sasha Levin To: stable@vger.kernel.org Cc: Tristan Madani , Stephen Smalley , Paul Moore , Sasha Levin Subject: [PATCH 5.15.y 3/3] selinux: avoid sk_socket dereference in selinux_sctp_bind_connect() Date: Thu, 23 Jul 2026 15:59:09 -0400 Message-ID: <20260723195909.3685525-3-sashal@kernel.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260723195909.3685525-1-sashal@kernel.org> References: <2026072006-eggshell-gulp-8828@gregkh> <20260723195909.3685525-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Tristan Madani [ Upstream commit 56acfeb10019e200ab6787d01f8d7cbe0f01526f ] selinux_sctp_bind_connect() dereferences sk->sk_socket to pass a struct socket * to selinux_socket_bind() and selinux_socket_connect_helper(). However, when the hook is invoked from the ASCONF softirq path (sctp_process_asconf), there is no file reference guaranteeing that sk->sk_socket is non-NULL. The setsockopt callers (bindx, connectx, set_primary, sendmsg connect) hold a file reference and are not affected. Both selinux_socket_bind() and selinux_socket_connect_helper() immediately resolve sock->sk, never using the struct socket * for anything else. Refactor the inner logic into helpers that take a struct sock * directly so that selinux_sctp_bind_connect() never needs to touch sk->sk_socket at all. Cc: stable@vger.kernel.org Fixes: d452930fd3b9 ("selinux: Add SCTP support") Suggested-by: Stephen Smalley Signed-off-by: Tristan Madani Reviewed-by: Stephen Smalley Tested-by: Stephen Smalley Signed-off-by: Paul Moore Signed-off-by: Sasha Levin --- security/selinux/hooks.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 94c4ce88fa9827..fa91dc75cdb598 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -4763,9 +4763,8 @@ static int selinux_socket_socketpair(struct socket *socka, Need to determine whether we should perform a name_bind permission check between the socket and the port number. */ -static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) +static int __selinux_socket_bind(struct sock *sk, struct sockaddr *address, int addrlen) { - struct sock *sk = sock->sk; struct sk_security_struct *sksec = selinux_sock(sk); u16 family; int err; @@ -4901,13 +4900,17 @@ static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, in return -EAFNOSUPPORT; } +static int selinux_socket_bind(struct socket *sock, struct sockaddr *address, int addrlen) +{ + return __selinux_socket_bind(sock->sk, address, addrlen); +} + /* This supports connect(2) and SCTP connect services such as sctp_connectx(3) * and sctp_sendmsg(3) as described in Documentation/security/SCTP.rst */ -static int selinux_socket_connect_helper(struct socket *sock, +static int selinux_socket_connect_helper(struct sock *sk, struct sockaddr *address, int addrlen) { - struct sock *sk = sock->sk; struct sk_security_struct *sksec = selinux_sock(sk); int err; @@ -5001,7 +5004,7 @@ static int selinux_socket_connect(struct socket *sock, int err; struct sock *sk = sock->sk; - err = selinux_socket_connect_helper(sock, address, addrlen); + err = selinux_socket_connect_helper(sk, address, addrlen); if (err) return err; @@ -5466,13 +5469,11 @@ static int selinux_sctp_bind_connect(struct sock *sk, int optname, int len, err = 0, walk_size = 0; void *addr_buf; struct sockaddr *addr; - struct socket *sock; if (!selinux_policycap_extsockclass()) return 0; /* Process one or more addresses that may be IPv4 or IPv6 */ - sock = sk->sk_socket; addr_buf = address; while (walk_size < addrlen) { @@ -5501,14 +5502,14 @@ static int selinux_sctp_bind_connect(struct sock *sk, int optname, case SCTP_PRIMARY_ADDR: case SCTP_SET_PEER_PRIMARY_ADDR: case SCTP_SOCKOPT_BINDX_ADD: - err = selinux_socket_bind(sock, addr, len); + err = __selinux_socket_bind(sk, addr, len); break; /* Connect checks */ case SCTP_SOCKOPT_CONNECTX: case SCTP_PARAM_SET_PRIMARY: case SCTP_PARAM_ADD_IP: case SCTP_SENDMSG_CONNECT: - err = selinux_socket_connect_helper(sock, addr, len); + err = selinux_socket_connect_helper(sk, addr, len); if (err) return err; -- 2.53.0