From 5963e8a3122471cadfe0eba41c4ceaeaa5c8bb4d Mon Sep 17 00:00:00 2001 From: Anton Vasilyev Date: Tue, 7 Aug 2018 13:59:05 +0300 Subject: [PATCH] serial: mxs-auart: Fix potential infinite loop MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit On the error path of mxs_auart_request_gpio_irq() is performed backward iterating with index i of enum type. Underline enum type may be unsigned char. In this case check (--i >= 0) will be always true and error handling goes into infinite loop. The patch changes the check so that it is valid for signed and unsigned types. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Anton Vasilyev Acked-by: Uwe Kleine-König Signed-off-by: Greg Kroah-Hartman --- drivers/tty/serial/mxs-auart.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/tty/serial/mxs-auart.c b/drivers/tty/serial/mxs-auart.c index 76aa289652f7..27235a526cce 100644 --- a/drivers/tty/serial/mxs-auart.c +++ b/drivers/tty/serial/mxs-auart.c @@ -1634,8 +1634,9 @@ static int mxs_auart_request_gpio_irq(struct mxs_auart_port *s) /* * If something went wrong, rollback. + * Be careful: i may be unsigned. */ - while (err && (--i >= 0)) + while (err && (i-- > 0)) if (irq[i] >= 0) free_irq(irq[i], s);