On Mon, Dec 28, 2020 at 12:01:44PM +0100, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
> The patch below does not apply to the 5.4-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@xxxxxxxxxxxxxxx>.
Sorry for the delay, here's the backport of 8f96c434dfbc to v5.4-stable:
-- >8 --
From: Lukas Wunner <lukas@xxxxxxxxx>
Date: Mon, 7 Dec 2020 09:17:02 +0100
Subject: [PATCH] spi: spi-geni-qcom: Fix use-after-free on unbind
commit 8f96c434dfbc85ffa755d6634c8c1cb2233fcf24 upstream.
spi_geni_remove() accesses the driver's private data after calling
spi_unregister_master() even though that function releases the last
reference on the spi_master and thereby frees the private data.
Fix by switching over to the new devm_spi_alloc_master() helper which
keeps the private data accessible until the driver has unbound.
Fixes: 561de45f72bd ("spi: spi-geni-qcom: Add SPI driver support for GENI based QUP")
Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v4.20+: 5e844cc37a5c: spi: Introduce device-managed SPI controller allocation
Cc: <stable@xxxxxxxxxxxxxxx> # v4.20+
Cc: Rajendra Nayak <rnayak@xxxxxxxxxxxxxx>
Cc: Girish Mahadevan <girishm@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/dfa1d8c41b8acdfad87ec8654cd124e6e3cb3f31.1607286887.git.lukas@xxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
[lukas: backport to v5.4.123]
Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
---
drivers/spi/spi-geni-qcom.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)
diff --git a/drivers/spi/spi-geni-qcom.c b/drivers/spi/spi-geni-qcom.c
index 6f3d64a1a2b3..01b53d816497 100644
--- a/drivers/spi/spi-geni-qcom.c
+++ b/drivers/spi/spi-geni-qcom.c
@@ -552,7 +552,7 @@ static int spi_geni_probe(struct platform_device *pdev)
return PTR_ERR(clk);
}
- spi = spi_alloc_master(&pdev->dev, sizeof(*mas));
+ spi = devm_spi_alloc_master(&pdev->dev, sizeof(*mas));
if (!spi)
return -ENOMEM;
@@ -599,7 +599,6 @@ static int spi_geni_probe(struct platform_device *pdev)
free_irq(mas->irq, spi);
spi_geni_probe_runtime_disable:
pm_runtime_disable(&pdev->dev);
- spi_master_put(spi);
return ret;
}
--
2.31.1
