spi: mpc52xx: Add cancel_work_sync before module remove

If we remove the module which will call mpc52xx_spi_remove
it will free 'ms' through spi_unregister_controller.
while the work ms->work will be used. The sequence of operations
that may lead to a UAF bug.

Fix it by ensuring that the work is canceled before proceeding with
the cleanup in mpc52xx_spi_remove.

Fixes: ca632f556697 ("spi: reorganize drivers")
Signed-off-by: Pei Xiao <[email protected]>
Link: https://patch.msgid.link/1f16f8ae0e50ca9adb1dc849bf2ac65a40c9ceb9.1732783000.git.xiaopei01@kylinos.cn
Signed-off-by: Mark Brown <[email protected]>

diff --git a/drivers/spi/spi-mpc52xx.c b/drivers/spi/spi-mpc52xx.c
index 036bfb7bf18902744d974c6077fea858730537a4..6d4dde15ac5451624baec13e7acdda5b3031bf11 100644 (file)
--- a/drivers/spi/spi-mpc52xx.c
+++ b/drivers/spi/spi-mpc52xx.c
@@ -520,6 +520,7 @@ static void mpc52xx_spi_remove(struct platform_device *op)
        struct mpc52xx_spi *ms = spi_controller_get_devdata(host);
        int i;
 
+       cancel_work_sync(&ms->work);
        free_irq(ms->irq0, ms);
        free_irq(ms->irq1, ms);