linux-kernel - [PATCH 4.4 38/96] fix a page leak in vhost_scsi_iov_to

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Tue, 28 Nov 2017 11:22:47 +0100
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Al Viro <viro@...iv.linux.org.uk>
Subject: [PATCH 4.4 38/96] fix a page leak in vhost_scsi_iov_to_sgl() error recovery

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Al Viro <viro@...iv.linux.org.uk>

commit 11d49e9d089ccec81be87c2386dfdd010d7f7f6e upstream.

we are advancing sg as we go, so the pages we need to drop in
case of error are *before* the current sg.

Signed-off-by: Al Viro <viro@...iv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/vhost/scsi.c |    5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

--- a/drivers/vhost/scsi.c
+++ b/drivers/vhost/scsi.c
@@ -703,6 +703,7 @@ vhost_scsi_iov_to_sgl(struct vhost_scsi_
 		      struct scatterlist *sg, int sg_count)
 {
 	size_t off = iter->iov_offset;
+	struct scatterlist *p = sg;
 	int i, ret;
 
 	for (i = 0; i < iter->nr_segs; i++) {
@@ -711,8 +712,8 @@ vhost_scsi_iov_to_sgl(struct vhost_scsi_
 
 		ret = vhost_scsi_map_to_sgl(cmd, base, len, sg, write);
 		if (ret < 0) {
-			for (i = 0; i < sg_count; i++) {
-				struct page *page = sg_page(&sg[i]);
+			while (p < sg) {
+				struct page *page = sg_page(p++);
 				if (page)
 					put_page(page);
 			}