Commit 56ea1075 authored Nov 16, 2015 by Mark Brown

spi: spidev: Hold spi_lock over all defererences of spi in release()



We use the spi_lock spinlock to protect against races between the device
being removed and file operations on the spidev.  This means that in the
removal path all references to the device need to be done under lock as
in removal we dropping references to the device.

Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

parent 8005c49d

drivers/spi/spidev.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -651,11 +651,11 @@ static int spidev_release(struct inode inode, struct file filp)
		kfree(spidev->rx_buffer);
		spidev->rx_buffer = NULL;

		spin_lock_irq(&spidev->spi_lock);
		if (spidev->spi)
		spidev->speed_hz = spidev->spi->max_speed_hz;

		/* ... after we unbound from the underlying device? */
		spin_lock_irq(&spidev->spi_lock);
		dofree = (spidev->spi == NULL);
		spin_unlock_irq(&spidev->spi_lock);

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