Patch "scsi: storvsc: fix memory leak on ring buffer busy" has been added to the 4.9-stable tree

[<gregkh@linuxfoundation.org>]

This is a note to let you know that I've just added the patch titled

    scsi: storvsc: fix memory leak on ring buffer busy

to the 4.9-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     scsi-storvsc-fix-memory-leak-on-ring-buffer-busy.patch
and it can be found in the queue-4.9 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 0208eeaa650c5c866a3242201678a19e6dc4a14e Mon Sep 17 00:00:00 2001
From: Long Li <longli@microsoft.com>
Date: Mon, 28 Aug 2017 17:43:59 -0700
Subject: scsi: storvsc: fix memory leak on ring buffer busy

From: Long Li <longli@microsoft.com>

commit 0208eeaa650c5c866a3242201678a19e6dc4a14e upstream.

When storvsc is sending I/O to Hyper-v, it may allocate a bigger buffer
descriptor for large data payload that can't fit into a pre-allocated
buffer descriptor. This bigger buffer is freed on return path.

If I/O request to Hyper-v fails due to ring buffer busy, the storvsc
allocated buffer descriptor should also be freed.

[mkp: applied by hand]

Fixes: be0cf6ca301c ("scsi: storvsc: Set the tablesize based on the information given by the host")
Signed-off-by: Long Li <longli@microsoft.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/scsi/storvsc_drv.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/drivers/scsi/storvsc_drv.c
+++ b/drivers/scsi/storvsc_drv.c
@@ -1559,6 +1559,8 @@ static int storvsc_queuecommand(struct S
 	ret = storvsc_do_io(dev, cmd_request);
 
 	if (ret == -EAGAIN) {
+		if (payload_sz > sizeof(cmd_request->mpb))
+			kfree(payload);
 		/* no more space */
 		return SCSI_MLQUEUE_DEVICE_BUSY;
 	}


Patches currently in stable-queue which might be from longli@microsoft.com are

queue-4.9/scsi-storvsc-fix-memory-leak-on-ring-buffer-busy.patch