[PATCH 3.18 18/56] can: mpc5xxx_can: check of_iomap return before use

From: Greg Kroah-Hartman
Date: Mon Sep 03 2018 - 12:50:42 EST


3.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Nicholas Mc Guire <hofrat@xxxxxxxxx>

[ Upstream commit b5c1a23b17e563b656cc9bb76ce5323b997d90e8 ]

of_iomap() can return NULL so that return needs to be checked and NULL
treated as failure. While at it also take care of the missing
of_node_put() in the error path.

Signed-off-by: Nicholas Mc Guire <hofrat@xxxxxxxxx>
Fixes: commit afa17a500a36 ("net/can: add driver for mscan family & mpc52xx_mscan")
Signed-off-by: Marc Kleine-Budde <mkl@xxxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/net/can/mscan/mpc5xxx_can.c | 5 +++++
1 file changed, 5 insertions(+)

--- a/drivers/net/can/mscan/mpc5xxx_can.c
+++ b/drivers/net/can/mscan/mpc5xxx_can.c
@@ -86,6 +86,11 @@ static u32 mpc52xx_can_get_clock(struct
return 0;
}
cdm = of_iomap(np_cdm, 0);
+ if (!cdm) {
+ of_node_put(np_cdm);
+ dev_err(&ofdev->dev, "can't map clock node!\n");
+ return 0;
+ }

if (in_8(&cdm->ipb_clk_sel) & 0x1)
freq *= 2;