This is a note to let you know that I've just added the patch titled
spi: bcm2835aux: Fix use-after-free on unbind
to the 5.9-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-bcm2835aux-fix-use-after-free-on-unbind.patch
and it can be found in the queue-5.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From e13ee6cc4781edaf8c7321bee19217e3702ed481 Mon Sep 17 00:00:00 2001
From: Lukas Wunner <lukas@xxxxxxxxx>
Date: Wed, 11 Nov 2020 20:07:30 +0100
Subject: spi: bcm2835aux: Fix use-after-free on unbind
From: Lukas Wunner <lukas@xxxxxxxxx>
commit e13ee6cc4781edaf8c7321bee19217e3702ed481 upstream.
bcm2835aux_spi_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: b9dd3f6d4172 ("spi: bcm2835aux: Fix controller unregister order")
Signed-off-by: Lukas Wunner <lukas@xxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> # v4.4+: 123456789abc: spi: Introduce device-managed SPI controller allocation
Cc: <stable@xxxxxxxxxxxxxxx> # v4.4+: b9dd3f6d4172: spi: bcm2835aux: Fix controller unregister order
Cc: <stable@xxxxxxxxxxxxxxx> # v4.4+
Link: https://lore.kernel.org/r/b290b06357d0c0bdee9cecc539b840a90630f101.1605121038.git.lukas@xxxxxxxxx
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/spi/spi-bcm2835aux.c | 21 +++++++--------------
1 file changed, 7 insertions(+), 14 deletions(-)
--- a/drivers/spi/spi-bcm2835aux.c
+++ b/drivers/spi/spi-bcm2835aux.c
@@ -494,7 +494,7 @@ static int bcm2835aux_spi_probe(struct p
unsigned long clk_hz;
int err;
- master = spi_alloc_master(&pdev->dev, sizeof(*bs));
+ master = devm_spi_alloc_master(&pdev->dev, sizeof(*bs));
if (!master)
return -ENOMEM;
@@ -524,29 +524,24 @@ static int bcm2835aux_spi_probe(struct p
/* the main area */
bs->regs = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(bs->regs)) {
- err = PTR_ERR(bs->regs);
- goto out_master_put;
- }
+ if (IS_ERR(bs->regs))
+ return PTR_ERR(bs->regs);
bs->clk = devm_clk_get(&pdev->dev, NULL);
if (IS_ERR(bs->clk)) {
- err = PTR_ERR(bs->clk);
dev_err(&pdev->dev, "could not get clk: %d\n", err);
- goto out_master_put;
+ return PTR_ERR(bs->clk);
}
bs->irq = platform_get_irq(pdev, 0);
- if (bs->irq <= 0) {
- err = bs->irq ? bs->irq : -ENODEV;
- goto out_master_put;
- }
+ if (bs->irq <= 0)
+ return bs->irq ? bs->irq : -ENODEV;
/* this also enables the HW block */
err = clk_prepare_enable(bs->clk);
if (err) {
dev_err(&pdev->dev, "could not prepare clock: %d\n", err);
- goto out_master_put;
+ return err;
}
/* just checking if the clock returns a sane value */
@@ -581,8 +576,6 @@ static int bcm2835aux_spi_probe(struct p
out_clk_disable:
clk_disable_unprepare(bs->clk);
-out_master_put:
- spi_master_put(master);
return err;
}
Patches currently in stable-queue which might be from lukas@xxxxxxxxx are
queue-5.9/spi-bcm2835aux-fix-use-after-free-on-unbind.patch
queue-5.9/spi-lpspi-fix-use-after-free-on-unbind.patch
queue-5.9/spi-npcm-fiu-don-t-leak-spi-master-in-probe-error-path.patch
queue-5.9/spi-introduce-device-managed-spi-controller-allocation.patch
