| Message ID | ad66e0a0ad96feb848814842ecf5b6a4539ef35c.1605121038.git.lukas@wunner.de (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | e1483ac030fb4c57734289742f1c1d38dca61e22 |
| Headers | show |
| Series | Use-after-free be gone | expand |
On 11/11/20 11:07 AM, Lukas Wunner wrote: > 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>
diff --git a/drivers/spi/spi-bcm2835.c b/drivers/spi/spi-bcm2835.c index 7104cf17b848..197485f2c2b2 100644 --- a/drivers/spi/spi-bcm2835.c +++ b/drivers/spi/spi-bcm2835.c @@ -1278,7 +1278,7 @@ static int bcm2835_spi_probe(struct platform_device *pdev) 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; @@ -1299,23 +1299,17 @@ static int bcm2835_spi_probe(struct platform_device *pdev) bs->ctlr = 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 = dev_err_probe(&pdev->dev, PTR_ERR(bs->clk), - "could not get clk\n"); - goto out_controller_put; - } + if (IS_ERR(bs->clk)) + return dev_err_probe(&pdev->dev, PTR_ERR(bs->clk), + "could not get clk\n"); 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); @@ -1349,8 +1343,6 @@ static int bcm2835_spi_probe(struct platform_device *pdev) bcm2835_dma_release(ctlr, bs); out_clk_disable: clk_disable_unprepare(bs->clk); -out_controller_put: - spi_controller_put(ctlr); return err; }
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> --- drivers/spi/spi-bcm2835.c | 24 ++++++++---------------- 1 file changed, 8 insertions(+), 16 deletions(-)