From: Hans Verkuil Date: Tue, 11 Jan 2011 20:48:21 +0000 (-0300) Subject: [media] v4l2-device: fix 'use-after-freed' oops X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=672dcd54774ea1b03da8f2baa1cdbf827927fc85;p=linux-beck.git [media] v4l2-device: fix 'use-after-freed' oops Fix a bug in v4l2_device_unregister where the sd pointer can be dereferenced after it was freed. Normally the i2c adapter is removed before this function is called. Removing the adapter will also unregister all subdevs on that adapter, so generally v4l2_device_unregister has nothing to do. However, in the case of a platform i2c bus that bus is generally not freed. In that case, after freeing the i2c subdevice the code will fall into the second block when it tests if the subdev is a SPI device. But by that time the subdev is already freed and the kernel oopses. The fix is trivial: continue with the loop after freeing the i2c or spi subdevice. Signed-off-by: Hans Verkuil Reported-by: Daniel Drake Signed-off-by: Mauro Carvalho Chehab --- diff --git a/drivers/media/video/v4l2-device.c b/drivers/media/video/v4l2-device.c index b24f002ffa67..ce64fe16bc60 100644 --- a/drivers/media/video/v4l2-device.c +++ b/drivers/media/video/v4l2-device.c @@ -100,6 +100,7 @@ void v4l2_device_unregister(struct v4l2_device *v4l2_dev) is a platform bus, then it is never deleted. */ if (client) i2c_unregister_device(client); + continue; } #endif #if defined(CONFIG_SPI) @@ -108,6 +109,7 @@ void v4l2_device_unregister(struct v4l2_device *v4l2_dev) if (spi) spi_unregister_device(spi); + continue; } #endif }