netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Sasha Levin <sasha.levin@oracle.com>
To: davem@davemloft.net, jmorris@namei.org, yoshfuji@linux-ipv6.org,
	kaber@trash.net
Cc: netdev@vger.kernel.org, linux-kernel@vger.kernel.org,
	Sasha Levin <sasha.levin@oracle.com>
Subject: [PATCH] iovec: make sure the caller actually wants anything in memcpy_fromiovecend
Date: Thu, 31 Jul 2014 23:00:35 -0400	[thread overview]
Message-ID: <1406862035-27818-1-git-send-email-sasha.levin@oracle.com> (raw)

Check for cases when the caller requests 0 bytes instead of running off
and dereferencing potentially invalid iovecs.

Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
---
 lib/iovec.c |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/iovec.c b/lib/iovec.c
index 7a7c2da..df3abd1 100644
--- a/lib/iovec.c
+++ b/lib/iovec.c
@@ -85,6 +85,10 @@ EXPORT_SYMBOL(memcpy_toiovecend);
 int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov,
 			int offset, int len)
 {
+	/* No data? Done! */
+	if (len == 0)
+		return 0;
+
 	/* Skip over the finished iovecs */
 	while (offset >= iov->iov_len) {
 		offset -= iov->iov_len;
-- 
1.7.10.4

             reply	other threads:[~2014-08-01  3:00 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-08-01  3:00 Sasha Levin [this message]
2014-08-02 22:26 ` [PATCH] iovec: make sure the caller actually wants anything in memcpy_fromiovecend David Miller

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=1406862035-27818-1-git-send-email-sasha.levin@oracle.com \
    --to=sasha.levin@oracle.com \
    --cc=davem@davemloft.net \
    --cc=jmorris@namei.org \
    --cc=kaber@trash.net \
    --cc=linux-kernel@vger.kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=yoshfuji@linux-ipv6.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).