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 3B418F9E8; Tue, 16 Jul 2024 15:41:34 +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=1721144494; cv=none; b=gzlxoRRYx2xQPf87tHk5zZ0z96obUNRrsNtswF0XgVcqOYTZOHynLel7COGgBdr9cjQ4zxXF45xP3zdBWfMKXFtiZJEoRqnx1M9VwUkeNyGeQefwjfk1wVZDQgiLwDTnvUHBuCvTrz9HGpWweTUV30w20Gw7+WyuiZ2aSZ5dDEo= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1721144494; c=relaxed/simple; bh=c9vinyLREDDORXd/8yvh7nasKt2mLmr3Nnj9LJzV8bM=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=bfuH75wt4+dt3uzuOZHgMIYzM2uKHMYPwSD2y4XSUvP/auOfhV5vySFAxqfbELn1sDd+ZAwkbE6XjtkvcPEQ95C3NYz6Ta0z2mqEHNfVncQK+y7gQazYll4yQ9NQmhP+YvyvxHpyTTAeHggZvAtvwFy86EThlmfvYxEGyGzOK7M= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=tpesJ1n0; 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="tpesJ1n0" Received: by smtp.kernel.org (Postfix) with ESMTPSA id B2632C116B1; Tue, 16 Jul 2024 15:41:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1721144494; bh=c9vinyLREDDORXd/8yvh7nasKt2mLmr3Nnj9LJzV8bM=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=tpesJ1n00OJRCsLvvxw7ngBmIziPFxuy3tTA1N3Gp/sOSwWfCkmKTAd0lIEfaNJBv LF8zMJcErRejPkzlXZcejL8GanGNzpMwNyaXhVfXfRJbtbBacE6Hq2MU+/ichwkbXb dDgo68PV9+p+su2pKBBr8J8Rth0kxI8St8+1Dr5U= 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 5.10 012/108] sctp: prefer struct_size over open coded arithmetic Date: Tue, 16 Jul 2024 17:30:27 +0200 Message-ID: <20240716152746.470524369@linuxfoundation.org> X-Mailer: git-send-email 2.45.2 In-Reply-To: <20240716152745.988603303@linuxfoundation.org> References: <20240716152745.988603303@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 5.10-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 bc4fe944ef858..79cf4cda2cf6d 100644 --- a/net/sctp/socket.c +++ b/net/sctp/socket.c @@ -6994,6 +6994,7 @@ 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)) @@ -7006,11 +7007,11 @@ 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