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 5BA04356A12; Tue, 21 Jul 2026 19:32:45 +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=1784662366; cv=none; b=irvwcNewapzpK/P/KrZ06ucnJOWcDgeHWnybnHzKX9On/PU00FXdUNBjGnwQxZKgI2JlG7QRiMvF+zOJINPJAFA3ulk0q0wq3tTHBHZTuaTSEK+803cWJefG3IqrKzQC/+7SQaYVj3PX3Hec0p+FgRTzU2RqfRtrqYCe1nMC0a0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784662366; c=relaxed/simple; bh=MK4gfkq5lH9fJk1tBNz2q4qHOdKM4m/Yo0eBk5POKZw=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=JJsdc6m++Hk5l7Le1/pbgDD5Igo6fr+4l/QrTO6uvRUgKJ5pCSjlRsyYp2szAR3TDw0zmr9hMgZa90FZUT6eRjYGWNJNBwc1mOWYvQl0KNrqzNooz9i660GmLi+JJn2FrcUpC3G/NqtXLQzKZGUBUBU9QEJYiV9O+07VMpk8wUI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=WYulsQ07; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="WYulsQ07" Received: by smtp.kernel.org (Postfix) with ESMTPSA id C17861F000E9; Tue, 21 Jul 2026 19:32:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1784662365; bh=UHKMNn8T9xfKWCmN3uDFSCH8zQa5Ezyli9PQHlTWX0w=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=WYulsQ07QX4Y1o1MDyxQBUTnKWyaKMdZ+X3Rdvaf5eAOqSHWflnYClKxJ6G4lmJqk XKHFYmErwqj6kfutTZbQq6585Q/H1N4Or296RYKkMD4r6gaQdE3vrK21dtslPZzyEN X31aFjMpUR91mhfut8VOY5aAZBovVmmHsmfxmh70= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Matthieu Buffet , =?UTF-8?q?Micka=C3=ABl=20Sala=C3=BCn?= , Sasha Levin Subject: [PATCH 6.12 0373/1276] landlock: Fix unmarked concurrent access to socket family Date: Tue, 21 Jul 2026 17:13:36 +0200 Message-ID: <20260721152454.454167512@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260721152446.065700225@linuxfoundation.org> References: <20260721152446.065700225@linuxfoundation.org> User-Agent: quilt/0.69 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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Matthieu Buffet [ Upstream commit 0ce4243509d1580349dd0d50624036d6b097e958 ] Socket family is read (twice) in a context where the socket is not locked, so another thread can setsockopt(IPV6_ADDRFORM) to write it concurrently. Add needed READ_ONCE() annotation. Use the proper macro to access __sk_common.skc_family like everywhere else. Fixes: fff69fb03dde ("landlock: Support network rules with TCP bind and connect") Signed-off-by: Matthieu Buffet Link: https://patch.msgid.link/20260609211511.85630-1-matthieu@buffet.re Link: https://patch.msgid.link/20260609211511.85630-2-matthieu@buffet.re [mic: Squash two patches, move variable to ease backport, fix comment formatting] Signed-off-by: Mickaël Salaün Signed-off-by: Sasha Levin --- security/landlock/net.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/security/landlock/net.c b/security/landlock/net.c index 53d479893475f8..9c9608924fbdbb 100644 --- a/security/landlock/net.c +++ b/security/landlock/net.c @@ -48,6 +48,7 @@ static int current_check_access_socket(struct socket *const sock, const int addrlen, access_mask_t access_request) { + unsigned short sock_family; __be16 port; layer_mask_t layer_masks[LANDLOCK_NUM_ACCESS_NET] = {}; const struct landlock_rule *rule; @@ -70,6 +71,12 @@ static int current_check_access_socket(struct socket *const sock, if (addrlen < offsetofend(typeof(*address), sa_family)) return -EINVAL; + /* + * The socket is not locked, so sk_family can change concurrently due to + * e.g. setsockopt(IPV6_ADDRFORM). + */ + sock_family = READ_ONCE(sock->sk->sk_family); + switch (address->sa_family) { case AF_UNSPEC: if (access_request == LANDLOCK_ACCESS_NET_CONNECT_TCP) { @@ -106,7 +113,7 @@ static int current_check_access_socket(struct socket *const sock, * these checks, but it is safer to return a proper * error and test consistency thanks to kselftest. */ - if (sock->sk->__sk_common.skc_family == AF_INET) { + if (sock_family == AF_INET) { const struct sockaddr_in *const sockaddr = (struct sockaddr_in *)address; @@ -154,7 +161,7 @@ static int current_check_access_socket(struct socket *const sock, * check, but it is safer to return a proper error and test * consistency thanks to kselftest. */ - if (address->sa_family != sock->sk->__sk_common.skc_family && + if (address->sa_family != sock_family && address->sa_family != AF_UNSPEC) return -EINVAL; -- 2.53.0