[PATCH 4.9 047/171] spi: img-spfi: fix potential double release

From: Greg Kroah-Hartman
Date: Thu Jan 02 2020 - 17:47:29 EST

From: Pan Bian <bianpan2016@xxxxxxx>

[ Upstream commit e9a8ba9769a0e354341bc6cc01b98aadcea1dfe9 ]

The channels spfi->tx_ch and spfi->rx_ch are not set to NULL after they
are released. As a result, they will be released again, either on the
error handling branch in the same function or in the corresponding
remove function, i.e. img_spfi_remove(). This patch fixes the bug by
setting the two members to NULL.

Signed-off-by: Pan Bian <bianpan2016@xxxxxxx>
Link: https://lore.kernel.org/r/1573007769-20131-1-git-send-email-bianpan2016@xxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
drivers/spi/spi-img-spfi.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/drivers/spi/spi-img-spfi.c b/drivers/spi/spi-img-spfi.c
index 7a37090dabbe..2e65b70c7879 100644
--- a/drivers/spi/spi-img-spfi.c
+++ b/drivers/spi/spi-img-spfi.c
@@ -673,6 +673,8 @@ static int img_spfi_probe(struct platform_device *pdev)
if (spfi->rx_ch)
+ spfi->tx_ch = NULL;
+ spfi->rx_ch = NULL;
dev_warn(spfi->dev, "Failed to get DMA channels, falling back to PIO mode\n");
} else {
master->dma_tx = spfi->tx_ch;