From 87153f7a04c9904625537d9a552eff56dfd5cef0 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 [ Upstream commit 5963e8a3122471cadfe0eba41c4ceaeaa5c8bb4d ] 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 Signed-off-by: Sasha Levin --- 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 34acdf29713d..4c188f4079b3 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);