This is a note to let you know that I've just added the patch titled media: davinci: vpif: fix use-after-free on driver unbind to the 5.15-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: media-davinci-vpif-fix-use-after-free-on-driver-unbi.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e5374a0d2e9679bb6d597bf0c47508d5b2316665 Author: Johan Hovold <johan@xxxxxxxxxx> Date: Wed Dec 22 15:20:24 2021 +0100 media: davinci: vpif: fix use-after-free on driver unbind [ Upstream commit 43acb728bbc40169d2e2425e84a80068270974be ] The driver allocates and registers two platform device structures during probe, but the devices were never deregistered on driver unbind. This results in a use-after-free on driver unbind as the device structures were allocated using devres and would be freed by driver core when remove() returns. Fix this by adding the missing deregistration calls to the remove() callback and failing probe on registration errors. Note that the platform device structures must be freed using a proper release callback to avoid leaking associated resources like device names. Fixes: 479f7a118105 ("[media] davinci: vpif: adaptions for DT support") Cc: stable@xxxxxxxxxxxxxxx # 4.12 Cc: Kevin Hilman <khilman@xxxxxxxxxxxx> Signed-off-by: Johan Hovold <johan@xxxxxxxxxx> Reviewed-by: Lad Prabhakar <prabhakar.csengg@xxxxxxxxx> Signed-off-by: Hans Verkuil <hverkuil-cisco@xxxxxxxxx> Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/media/platform/davinci/vpif.c b/drivers/media/platform/davinci/vpif.c index 5658c7f148d7..8ffc01c606d0 100644 --- a/drivers/media/platform/davinci/vpif.c +++ b/drivers/media/platform/davinci/vpif.c @@ -41,6 +41,11 @@ MODULE_ALIAS("platform:" VPIF_DRIVER_NAME); #define VPIF_CH2_MAX_MODES 15 #define VPIF_CH3_MAX_MODES 2 +struct vpif_data { + struct platform_device *capture; + struct platform_device *display; +}; + DEFINE_SPINLOCK(vpif_lock); EXPORT_SYMBOL_GPL(vpif_lock); @@ -423,11 +428,19 @@ int vpif_channel_getfid(u8 channel_id) } EXPORT_SYMBOL(vpif_channel_getfid); +static void vpif_pdev_release(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + + kfree(pdev); +} + static int vpif_probe(struct platform_device *pdev) { static struct resource *res, *res_irq; struct platform_device *pdev_capture, *pdev_display; struct device_node *endpoint = NULL; + struct vpif_data *data; int ret; res = platform_get_resource(pdev, IORESOURCE_MEM, 0); @@ -435,6 +448,12 @@ static int vpif_probe(struct platform_device *pdev) if (IS_ERR(vpif_base)) return PTR_ERR(vpif_base); + data = kzalloc(sizeof(*data), GFP_KERNEL); + if (!data) + return -ENOMEM; + + platform_set_drvdata(pdev, data); + pm_runtime_enable(&pdev->dev); pm_runtime_get(&pdev->dev); @@ -462,49 +481,75 @@ static int vpif_probe(struct platform_device *pdev) goto err_put_rpm; } - pdev_capture = devm_kzalloc(&pdev->dev, sizeof(*pdev_capture), - GFP_KERNEL); - if (pdev_capture) { - pdev_capture->name = "vpif_capture"; - pdev_capture->id = -1; - pdev_capture->resource = res_irq; - pdev_capture->num_resources = 1; - pdev_capture->dev.dma_mask = pdev->dev.dma_mask; - pdev_capture->dev.coherent_dma_mask = pdev->dev.coherent_dma_mask; - pdev_capture->dev.parent = &pdev->dev; - platform_device_register(pdev_capture); - } else { - dev_warn(&pdev->dev, "Unable to allocate memory for pdev_capture.\n"); + pdev_capture = kzalloc(sizeof(*pdev_capture), GFP_KERNEL); + if (!pdev_capture) { + ret = -ENOMEM; + goto err_put_rpm; } - pdev_display = devm_kzalloc(&pdev->dev, sizeof(*pdev_display), - GFP_KERNEL); - if (pdev_display) { - pdev_display->name = "vpif_display"; - pdev_display->id = -1; - pdev_display->resource = res_irq; - pdev_display->num_resources = 1; - pdev_display->dev.dma_mask = pdev->dev.dma_mask; - pdev_display->dev.coherent_dma_mask = pdev->dev.coherent_dma_mask; - pdev_display->dev.parent = &pdev->dev; - platform_device_register(pdev_display); - } else { - dev_warn(&pdev->dev, "Unable to allocate memory for pdev_display.\n"); + pdev_capture->name = "vpif_capture"; + pdev_capture->id = -1; + pdev_capture->resource = res_irq; + pdev_capture->num_resources = 1; + pdev_capture->dev.dma_mask = pdev->dev.dma_mask; + pdev_capture->dev.coherent_dma_mask = pdev->dev.coherent_dma_mask; + pdev_capture->dev.parent = &pdev->dev; + pdev_capture->dev.release = vpif_pdev_release; + + ret = platform_device_register(pdev_capture); + if (ret) + goto err_put_pdev_capture; + + pdev_display = kzalloc(sizeof(*pdev_display), GFP_KERNEL); + if (!pdev_display) { + ret = -ENOMEM; + goto err_put_pdev_capture; } + pdev_display->name = "vpif_display"; + pdev_display->id = -1; + pdev_display->resource = res_irq; + pdev_display->num_resources = 1; + pdev_display->dev.dma_mask = pdev->dev.dma_mask; + pdev_display->dev.coherent_dma_mask = pdev->dev.coherent_dma_mask; + pdev_display->dev.parent = &pdev->dev; + pdev_display->dev.release = vpif_pdev_release; + + ret = platform_device_register(pdev_display); + if (ret) + goto err_put_pdev_display; + + data->capture = pdev_capture; + data->display = pdev_display; + return 0; +err_put_pdev_display: + platform_device_put(pdev_display); +err_put_pdev_capture: + platform_device_put(pdev_capture); err_put_rpm: pm_runtime_put(&pdev->dev); pm_runtime_disable(&pdev->dev); + kfree(data); return ret; } static int vpif_remove(struct platform_device *pdev) { + struct vpif_data *data = platform_get_drvdata(pdev); + + if (data->capture) + platform_device_unregister(data->capture); + if (data->display) + platform_device_unregister(data->display); + pm_runtime_put(&pdev->dev); pm_runtime_disable(&pdev->dev); + + kfree(data); + return 0; }