pinctrl: imx: reset group index on probe
authorStefan Agner <stefan@agner.ch>
Tue, 18 Oct 2016 21:09:15 +0000 (14:09 -0700)
committerLinus Walleij <linus.walleij@linaro.org>
Mon, 31 Oct 2016 20:25:15 +0000 (21:25 +0100)
commit9999fe5df58773489b9564467b5c8cfb364e0b80
tree85eb4e7a1fbcd5861ae84db0bf0f0da1a25b6a3b
parent0553d8d0b03ad58f9917460c40a2e2b680f5bfdb
pinctrl: imx: reset group index on probe

Group index is incremented on every new group parsed. Since the
field is part of struct imx_pinctrl_soc_info, which is typically
a global variable passed by the individual pinctrl-imx.c based
driver, it does not get cleared automatically when re-probing the
driver. This lead imx_pinctrl_parse_functions passing a group
pointer which is outside of the allocated group space on second
probe and onwards. Typically this ended up in a NULL pointer
dereference when accessing the name field like this:
Unable to handle kernel NULL pointer dereference at virtual address 00000000
...
PC is at strcmp+0x18/0x44
LR is at imx_dt_node_to_map+0xc4/0x290

Avoid this by setting group_index to 0 on probe.

This has been observed when using DEBUG_TEST_DRIVER_REMOVE.

Signed-off-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
drivers/pinctrl/freescale/pinctrl-imx.c