lkml.org 
[lkml]   [2020]   [Dec]   [1]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 5.4 02/98] spi: bcm2835: Fix use-after-free on unbind
Date
From: Lukas Wunner <lukas@wunner.de>

commit e1483ac030fb4c57734289742f1c1d38dca61e22 upstream

bcm2835_spi_remove() accesses the driver's private data after calling
spi_unregister_controller() even though that function releases the last
reference on the spi_controller 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: f8043872e796 ("spi: add driver for BCM2835")
Reported-by: Sascha Hauer <s.hauer@pengutronix.de>
Reported-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Lukas Wunner <lukas@wunner.de>
Cc: <stable@vger.kernel.org> # v3.10+: 123456789abc: spi: Introduce device-managed SPI controller allocation
Cc: <stable@vger.kernel.org> # v3.10+
Cc: Vladimir Oltean <olteanv@gmail.com>
Tested-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Link: https://lore.kernel.org/r/ad66e0a0ad96feb848814842ecf5b6a4539ef35c.1605121038.git.lukas@wunner.de
Signed-off-by: Mark Brown <broonie@kernel.org>
[sudip: dev_err_probe() not yet available]
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/spi/spi-bcm2835.c | 18 ++++++------------
1 file changed, 6 insertions(+), 12 deletions(-)

--- a/drivers/spi/spi-bcm2835.c
+++ b/drivers/spi/spi-bcm2835.c
@@ -1264,7 +1264,7 @@ static int bcm2835_spi_probe(struct plat
struct bcm2835_spi *bs;
int err;

- ctlr = spi_alloc_master(&pdev->dev, ALIGN(sizeof(*bs),
+ ctlr = devm_spi_alloc_master(&pdev->dev, ALIGN(sizeof(*bs),
dma_get_cache_alignment()));
if (!ctlr)
return -ENOMEM;
@@ -1284,23 +1284,19 @@ static int bcm2835_spi_probe(struct plat
bs = spi_controller_get_devdata(ctlr);

bs->regs = devm_platform_ioremap_resource(pdev, 0);
- if (IS_ERR(bs->regs)) {
- err = PTR_ERR(bs->regs);
- goto out_controller_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_controller_put;
+ return err;
}

bs->irq = platform_get_irq(pdev, 0);
- if (bs->irq <= 0) {
- err = bs->irq ? bs->irq : -ENODEV;
- goto out_controller_put;
- }
+ if (bs->irq <= 0)
+ return bs->irq ? bs->irq : -ENODEV;

clk_prepare_enable(bs->clk);

@@ -1330,8 +1326,6 @@ static int bcm2835_spi_probe(struct plat

out_clk_disable:
clk_disable_unprepare(bs->clk);
-out_controller_put:
- spi_controller_put(ctlr);
return err;
}


\
 
 \ /
  Last update: 2020-12-01 10:41    [W:0.237 / U:6.336 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site