[PATCH -next] hte: fix possible use-after-free in tegra_hte_test_remove()

From: Yang Yingliang
Date: Fri May 06 2022 - 04:37:54 EST


del_timer() does not wait until the timer handler finishing.
This means that the timer handler may still be running after
the driver's remove function has finished, which would result
in a use-after-free.
Fix it by calling del_timer_sync(), which makes sure the timer
handler has finished.

Reported-by: Hulk Robot <hulkci@xxxxxxxxxx>
Signed-off-by: Yang Yingliang <yangyingliang@xxxxxxxxxx>
---
drivers/hte/hte-tegra194-test.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/hte/hte-tegra194-test.c b/drivers/hte/hte-tegra194-test.c
index bc3ab18dfdc5..f69a274a7d8d 100644
--- a/drivers/hte/hte-tegra194-test.c
+++ b/drivers/hte/hte-tegra194-test.c
@@ -220,7 +220,7 @@ static int tegra_hte_test_remove(struct platform_device *pdev)
free_irq(hte.gpio_in_irq, &hte);
gpiod_put(hte.gpio_in);
gpiod_put(hte.gpio_out);
- del_timer(&hte.timer);
+ del_timer_sync(&hte.timer);

return 0;
}
--
2.25.1