All of lore.kernel.org
 help / color / mirror / Atom feed
From: Len Baker <len.baker@gmx.com>
To: James Smart <james.smart@broadcom.com>,
	Ram Vegesna <ram.vegesna@broadcom.com>,
	"James E.J. Bottomley" <jejb@linux.ibm.com>,
	"Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Len Baker <len.baker@gmx.com>, Kees Cook <keescook@chromium.org>,
	Hannes Reinecke <hare@suse.de>,
	linux-scsi@vger.kernel.org, target-devel@vger.kernel.org,
	linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] scsi: elx: libefc: Prefer kcalloc over open coded arithmetic
Date: Sun,  5 Sep 2021 08:24:48 +0200	[thread overview]
Message-ID: <20210905062448.6587-1-len.baker@gmx.com> (raw)

As noted in the "Deprecated Interfaces, Language Features, Attributes,
and Conventions" documentation [1], size calculations (especially
multiplication) should not be performed in memory allocator (or similar)
function arguments due to the risk of them overflowing. This could lead
to values wrapping around and a smaller allocation being made than the
caller was expecting. Using those allocations could lead to linear
overflows of heap memory and other misbehaviors.

So, use the purpose specific kcalloc() function instead of the argument
count * size in the kzalloc() function.

[1] https://www.kernel.org/doc/html/v5.14/process/deprecated.html#open-coded-arithmetic-in-allocator-arguments

Signed-off-by: Len Baker <len.baker@gmx.com>
---
 drivers/scsi/elx/libefc/efc_fabric.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/elx/libefc/efc_fabric.c b/drivers/scsi/elx/libefc/efc_fabric.c
index d397220d9e54..f9412437ad47 100644
--- a/drivers/scsi/elx/libefc/efc_fabric.c
+++ b/drivers/scsi/elx/libefc/efc_fabric.c
@@ -686,7 +686,7 @@ efc_process_gidpt_payload(struct efc_node *node,
 	}

 	/* Allocate a buffer for all nodes */
-	active_nodes = kzalloc(port_count * sizeof(*active_nodes), GFP_ATOMIC);
+	active_nodes = kcalloc(port_count, sizeof(*active_nodes), GFP_ATOMIC);
 	if (!active_nodes) {
 		node_printf(node, "efc_malloc failed\n");
 		return -EIO;
--
2.25.1


             reply	other threads:[~2021-09-05  6:25 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-09-05  6:24 Len Baker [this message]
2021-09-07 16:55 ` [PATCH] scsi: elx: libefc: Prefer kcalloc over open coded arithmetic James Smart
2021-09-22  4:45 ` Martin K. Petersen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210905062448.6587-1-len.baker@gmx.com \
    --to=len.baker@gmx.com \
    --cc=hare@suse.de \
    --cc=james.smart@broadcom.com \
    --cc=jejb@linux.ibm.com \
    --cc=keescook@chromium.org \
    --cc=linux-hardening@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-scsi@vger.kernel.org \
    --cc=martin.petersen@oracle.com \
    --cc=ram.vegesna@broadcom.com \
    --cc=target-devel@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.