Patch "mmc: sdhci: plug DMA mapping leak on error" has been added to the 4.5-stable tree

Patch "mmc: sdhci: plug DMA mapping leak on error" has been added to the 4.5-stable tree

[gregkh]

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

    mmc: sdhci: plug DMA mapping leak on error

to the 4.5-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:
     mmc-sdhci-plug-dma-mapping-leak-on-error.patch
and it can be found in the queue-4.5 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 054cedff5e025a54ceefff891c6ea42ee8b37eab Mon Sep 17 00:00:00 2001
From: Russell King <rmk+kernel@arm.linux.org.uk>
Date: Tue, 26 Jan 2016 13:40:42 +0000
Subject: mmc: sdhci: plug DMA mapping leak on error

From: Russell King <rmk+kernel@arm.linux.org.uk>

commit 054cedff5e025a54ceefff891c6ea42ee8b37eab upstream.

If we terminate a command early, we fail to properly clean up the DMA
mappings for the data part of the request.  Put this clean up to the
tasklet, which is the common path for finishing a request so we always
clean up after ourselves.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
[ Split original patch so that it now contains only the fix ]
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Tested-by: Gregory CLEMENT <gregory.clement@free-electrons.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/mmc/host/sdhci.c |   16 ++++++++++++++++
 1 file changed, 16 insertions(+)

--- a/drivers/mmc/host/sdhci.c
+++ b/drivers/mmc/host/sdhci.c
@@ -2207,6 +2207,22 @@ static void sdhci_tasklet_finish(unsigne
 	mrq = host->mrq;
 
 	/*
+	 * Always unmap the data buffers if they were mapped by
+	 * sdhci_prepare_data() whenever we finish with a request.
+	 * This avoids leaking DMA mappings on error.
+	 */
+	if (host->flags & SDHCI_REQ_USE_DMA) {
+		struct mmc_data *data = mrq->data;
+
+		if (data && data->host_cookie == COOKIE_MAPPED) {
+			dma_unmap_sg(mmc_dev(host->mmc), data->sg, data->sg_len,
+				     (data->flags & MMC_DATA_READ) ?
+				     DMA_FROM_DEVICE : DMA_TO_DEVICE);
+			data->host_cookie = COOKIE_UNMAPPED;
+		}
+	}
+
+	/*
 	 * The controller needs a reset of internal state machines
 	 * upon error conditions.
 	 */


Patches currently in stable-queue which might be from rmk+kernel@arm.linux.org.uk are

queue-4.5/mmc-sdhci-fix-command-response-crc-error-handling.patch
queue-4.5/mmc-sdhci-avoid-unnecessary-mapping-unmapping-of-align-buffer.patch
queue-4.5/mmc-sdhci-move-initialisation-of-command-error-member.patch
queue-4.5/mmc-sdhci-fix-data-timeout-part-2.patch
queue-4.5/mmc-sdhci-clean-up-command-error-handling.patch
queue-4.5/mmc-sdhci-further-fix-for-dma-unmapping-in-sdhci_post_req.patch
queue-4.5/mmc-sdhci-pxav3-fix-higher-speed-mode-capabilities.patch
queue-4.5/mmc-sdhci-fix-data-timeout-part-1.patch
queue-4.5/mmc-sdhci-plug-dma-mapping-leak-on-error.patch