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

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.

Fixes: fa236a7ef240 ("spi: bcm-qspi: Add Broadcom MSPI driver")
Signed-off-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org

1 files changed, 5 insertions, 4 deletions

diff --git a/drivers/spi/spi-bcm-qspi.c b/drivers/spi/spi-bcm-qspi.c
index 6ef6c44f39f5..a172ab299e80 100644
--- a/drivers/spi/spi-bcm-qspi.c
+++ b/drivers/spi/spi-bcm-qspi.c
@@ -1250,7 +1250,7 @@ int bcm_qspi_probe(struct platform_device *pdev,
                         goto qspi_probe_err;
                 }
         } else {
-                goto qspi_probe_err;
+                goto qspi_resource_err;
         }
 
         res = platform_get_resource_byname(pdev, IORESOURCE_MEM, "bspi");
@@ -1272,7 +1272,7 @@ int bcm_qspi_probe(struct platform_device *pdev,
                 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;
                 }
         }
 
@@ -1280,7 +1280,7 @@ int bcm_qspi_probe(struct platform_device *pdev,
                                 GFP_KERNEL);
         if (!qspi->dev_ids) {
                 ret = -ENOMEM;
-                goto qspi_probe_err;
+                goto qspi_resource_err;
         }
 
         for (val = 0; val < num_irqs; val++) {
@@ -1369,8 +1369,9 @@ 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 */