linux-kernel - [PATCH V2 07/10] Drivers: hv: vmbus: Fix a bug in rescind processing in vmbus_close

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]

Message-Id: <1426706970-32472-7-git-send-email-kys@microsoft.com>
Date:	Wed, 18 Mar 2015 12:29:27 -0700
From:	"K. Y. Srinivasan" <kys@...rosoft.com>
To:	gregkh@...uxfoundation.org, linux-kernel@...r.kernel.org,
	devel@...uxdriverproject.org, olaf@...fle.de, apw@...onical.com,
	vkuznets@...hat.com
Cc:	"K. Y. Srinivasan" <kys@...rosoft.com>
Subject: [PATCH V2 07/10] Drivers: hv: vmbus: Fix a bug in rescind processing in vmbus_close_internal()

When a channel has been rescinded, the close operation is a noop.
Restructure the code so we deal with the rescind condition after
we properly cleanup the channel. I would like to thank
Dexuan Cui <decui@...rosoft.com> for observing this problem.
The current code leaks memory when the channel is rescinded.

The current char-next branch is broken and this patch fixes
the bug.

Signed-off-by: K. Y. Srinivasan <kys@...rosoft.com>
---
 drivers/hv/channel.c |   15 ++++++---------
 1 files changed, 6 insertions(+), 9 deletions(-)

diff --git a/drivers/hv/channel.c b/drivers/hv/channel.c
index da53180..2c8206d 100644
--- a/drivers/hv/channel.c
+++ b/drivers/hv/channel.c
@@ -501,15 +501,6 @@ static int vmbus_close_internal(struct vmbus_channel *channel)
 		put_cpu();
 	}
 
-	/*
-	 * If the channel has been rescinded; process device removal.
-	 */
-	if (channel->rescind) {
-		hv_process_channel_removal(channel,
-					   channel->offermsg.child_relid);
-		return 0;
-	}
-
 	/* Send a closing message */
 
 	msg = &channel->close_msg.msg;
@@ -549,6 +540,12 @@ static int vmbus_close_internal(struct vmbus_channel *channel)
 	free_pages((unsigned long)channel->ringbuffer_pages,
 		get_order(channel->ringbuffer_pagecount * PAGE_SIZE));
 
+	/*
+	 * If the channel has been rescinded; process device removal.
+	 */
+	if (channel->rescind)
+		hv_process_channel_removal(channel,
+					   channel->offermsg.child_relid);
 	return ret;
 }
 
-- 
1.7.4.1

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/