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 429F5E541; Tue, 16 Jul 2024 15:34:31 +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=1721144071; cv=none; b=cKM7ip50NEdvSZeqRUgFVUWqk7TG4tiRuEOKhK32KSUpcienF7F9cREzQuEEAYfaegzS4hvxKJWWM18M2XedTtkUqp1bDMhf0A+GRNeSTL+Pmva+7cUq+hh2JigtjnZsFijH+G1CNos05kYMI+gOeqAeNSEiAJ4668ppf9RQAp8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721144071; c=relaxed/simple; bh=n47Se4qgNdZDTjenWrtSSWoJLJlVrw8DqlhSUe59TbI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ieZ27igURAT9JNRSDt0Jk/uU6inZufCdZDJb0Tqk+jnPmgwtf4aPoKjVqAprB0BMgcq6ESE3BSE1O+4Q+fkq0mhk/nvBngW14X4AiPVCV1eYysQ6w7p+SoopNRCDllDWT6bRe3UrFATKi38MXlro5QZFiO0P3LNO56Ow75RYQKE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=XWIBOsh7; 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="XWIBOsh7" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BC19AC116B1; Tue, 16 Jul 2024 15:34:30 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721144071; bh=n47Se4qgNdZDTjenWrtSSWoJLJlVrw8DqlhSUe59TbI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=XWIBOsh73AsJiNiLAOI9mVVWdayIyo1H6/IzTWSZAQbwDZZUq+t0bncAWBmdVxUF7 v+fIwTttFmsSF2cCInNty/oxwSW/HzITclnTkxy9LzQWSY8fnOPmOKFHshErl++daC 5rNCSCWximWjq/QhWkzWW0c6OkW9LVBTkboRRX6s= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Erick Archer , Xin Long , Kees Cook , Paolo Abeni , Sasha Levin Subject: [PATCH 4.19 06/66] sctp: prefer struct_size over open coded arithmetic Date: Tue, 16 Jul 2024 17:30:41 +0200 Message-ID: <20240716152738.410985425@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240716152738.161055634@linuxfoundation.org> References: <20240716152738.161055634@linuxfoundation.org> User-Agent: quilt/0.67 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 4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Erick Archer [ Upstream commit e5c5f3596de224422561d48eba6ece5210d967b3 ] This is an effort to get rid of all multiplications from allocation functions in order to prevent integer overflows [1][2]. As the "ids" variable is a pointer to "struct sctp_assoc_ids" and this structure ends in a flexible array: struct sctp_assoc_ids { [...] sctp_assoc_t gaids_assoc_id[]; }; the preferred way in the kernel is to use the struct_size() helper to do the arithmetic instead of the calculation "size + size * count" in the kmalloc() function. Also, refactor the code adding the "ids_size" variable to avoid sizing twice. This way, the code is more readable and safer. This code was detected with the help of Coccinelle, and audited and modified manually. Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments [1] Link: https://github.com/KSPP/linux/issues/160 [2] Signed-off-by: Erick Archer Acked-by: Xin Long Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/PAXPR02MB724871DB78375AB06B5171C88B152@PAXPR02MB7248.eurprd02.prod.outlook.com Signed-off-by: Paolo Abeni Signed-off-by: Sasha Levin --- net/sctp/socket.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-) diff --git a/net/sctp/socket.c b/net/sctp/socket.c index f954d3c8876db..c429a1a2bfe23 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -6801,6 +6801,7 @@ static int sctp_getsockopt_assoc_ids(struct sock *sk, int len, struct sctp_sock *sp = sctp_sk(sk); struct sctp_association *asoc; struct sctp_assoc_ids *ids; + size_t ids_size; u32 num = 0; if (sctp_style(sk, TCP)) @@ -6813,11 +6814,11 @@ static int sctp_getsockopt_assoc_ids(struct sock *sk, int len, num++; } - if (len < sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num) + ids_size = struct_size(ids, gaids_assoc_id, num); + if (len < ids_size) return -EINVAL; - len = sizeof(struct sctp_assoc_ids) + sizeof(sctp_assoc_t) * num; - + len = ids_size; ids = kmalloc(len, GFP_USER | __GFP_NOWARN); if (unlikely(!ids)) return -ENOMEM; -- 2.43.0