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From:   Sherry Sun <sherry.sun@nxp.com>
To:     gregkh@linuxfoundation.org, jirislaby@kernel.org
Cc:     linux-serial@vger.kernel.org, linux-kernel@vger.kernel.org,
        linux-imx@nxp.com
Subject: [PATCH 1/2] tty: serial: fsl_lpuart: fix the potential bug of division or modulo by zero
Date:   Mon, 26 Apr 2021 15:49:34 +0800
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This issue is reported by Coverity Check.
In lpuart32_console_get_options, division or modulo by zero may results
in undefined behavior.

Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
---
 drivers/tty/serial/fsl_lpuart.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c
index 794035041744..777d54b593f8 100644
--- a/drivers/tty/serial/fsl_lpuart.c
+++ b/drivers/tty/serial/fsl_lpuart.c
@@ -2414,6 +2414,9 @@ lpuart32_console_get_options(struct lpuart_port *sport, int *baud,
 
 	bd = lpuart32_read(&sport->port, UARTBAUD);
 	bd &= UARTBAUD_SBR_MASK;
+	if (!bd)
+		return;
+
 	sbr = bd;
 	uartclk = lpuart_get_baud_clk_rate(sport);
 	/*
-- 
2.17.1