Patch "spi: bcm-qspi: Fix use after free in bcm_qspi_probe() in error path" has been added to the 4.9-stable tree

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

spi: bcm-qspi: Fix use after free in bcm_qspi_probe() in error path

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:
spi-bcm-qspi-fix-use-after-free-in-bcm_qspi_probe-in-error-path.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 <[email protected]> know about it.

From: Florian Fainelli <[email protected]>
Date: Wed, 11 Oct 2017 14:59:22 -0700
Subject: spi: bcm-qspi: Fix use after free in bcm_qspi_probe() in error path

From: Florian Fainelli <[email protected]>

commit c0368e4db4a3e8a3dce40f3f621c06e14c560d79 upstream.

There was an inversion in how the error path in bcm_qspi_probe() is done which would make us trip over a KASAN use-after-free report. Turns out that qspi->dev_ids does not get allocated until later in the probe process. Fix this by introducing a new lable: qspi_resource_err which takes care of cleaning up the SPI master instance.

---
 drivers/spi/spi-bcm-qspi.c |    9 +++++----
 1 file changed, 5 insertions(+), 4 deletions(-)

@@ -1215,7 +1215,7 @@ int bcm_qspi_probe(struct platform_devic
 			goto qspi_probe_err;
 		}
 	} else {
-		goto qspi_probe_err;
+		goto qspi_resource_err;
 	}
 
 	res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "bspi");

@@ -1237,7 +1237,7 @@ int bcm_qspi_probe(struct platform_devic
 		qspi->base[CHIP_SELECT]  = devm_ioremap_resource(dev, res);
 		if (IS_ERR(qspi->base[CHIP_SELECT])) {
 			ret = PTR_ERR(qspi->base[CHIP_SELECT]);
-			goto qspi_probe_err;
+			goto qspi_resource_err;
 		}
 	}
 

@@ -1245,7 +1245,7 @@ int bcm_qspi_probe(struct platform_devic
 				GFP_KERNEL);
 	if (!qspi->dev_ids) {
 		ret = -ENOMEM;
-		goto qspi_probe_err;
+		goto qspi_resource_err;
 	}
 
 	for (val = 0; val < num_irqs; val++) {

@@ -1334,8 +1334,9 @@ qspi_reg_err:
 	bcm_qspi_hw_uninit(qspi);
 	clk_disable_unprepare(qspi->clk);
 qspi_probe_err:
-	spi_master_put(master);
 	kfree(qspi->dev_ids);
+qspi_resource_err:
+	spi_master_put(master);
 	return ret;
 }
 /* probe function to be called by SoC specific platform driver probe */

Patches currently in stable-queue which might be from [email protected] are

queue-4.9/spi-bcm-qspi-fix-use-after-free-in-bcm_qspi_probe-in-error-path.patch