From b9130b776ee481acbc27a7e56d98df75680de369 Mon Sep 17 00:00:00 2001 From: Tony Lindgren Date: Tue, 24 Jan 2012 16:28:08 -0800 Subject: [PATCH] pinctrl: add checks for empty function names This is needed as otherwise we can get the following when dealing with buggy data in a pinmux driver for pinmux_search_function: Unable to handle kernel NULL pointer dereference at virtual address 00000000 ... PC is at strcmp+0xc/0x34 LR is at pinmux_get+0x350/0x8f4 ... As we need pctldev initialized to call ops->list_functions, let's initialize it before check_ops calls and pass the pctldev to the check_ops functions. Do this for both pinmux and pinconf check_ops functions. Signed-off-by: Tony Lindgren Signed-off-by: Linus Walleij --- drivers/pinctrl/core.c | 40 +++++++++++++++++++-------------------- drivers/pinctrl/pinconf.c | 4 +++- drivers/pinctrl/pinconf.h | 4 ++-- drivers/pinctrl/pinmux.c | 17 ++++++++++++++++- drivers/pinctrl/pinmux.h | 4 ++-- 5 files changed, 43 insertions(+), 26 deletions(-) diff --git a/drivers/pinctrl/core.c b/drivers/pinctrl/core.c index d9d35fcbfc6b..8fe15cf15ac8 100644 --- a/drivers/pinctrl/core.c +++ b/drivers/pinctrl/core.c @@ -583,26 +583,6 @@ struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc, if (pctldesc->name == NULL) return NULL; - /* If we're implementing pinmuxing, check the ops for sanity */ - if (pctldesc->pmxops) { - ret = pinmux_check_ops(pctldesc->pmxops); - if (ret) { - pr_err("%s pinmux ops lacks necessary functions\n", - pctldesc->name); - return NULL; - } - } - - /* If we're implementing pinconfig, check the ops for sanity */ - if (pctldesc->confops) { - ret = pinconf_check_ops(pctldesc->confops); - if (ret) { - pr_err("%s pin config ops lacks necessary functions\n", - pctldesc->name); - return NULL; - } - } - pctldev = kzalloc(sizeof(struct pinctrl_dev), GFP_KERNEL); if (pctldev == NULL) return NULL; @@ -617,6 +597,26 @@ struct pinctrl_dev *pinctrl_register(struct pinctrl_desc *pctldesc, mutex_init(&pctldev->gpio_ranges_lock); pctldev->dev = dev; + /* If we're implementing pinmuxing, check the ops for sanity */ + if (pctldesc->pmxops) { + ret = pinmux_check_ops(pctldev); + if (ret) { + pr_err("%s pinmux ops lacks necessary functions\n", + pctldesc->name); + goto out_err; + } + } + + /* If we're implementing pinconfig, check the ops for sanity */ + if (pctldesc->confops) { + ret = pinconf_check_ops(pctldev); + if (ret) { + pr_err("%s pin config ops lacks necessary functions\n", + pctldesc->name); + goto out_err; + } + } + /* Register all the pins */ pr_debug("try to register %d pins on %s...\n", pctldesc->npins, pctldesc->name); diff --git a/drivers/pinctrl/pinconf.c b/drivers/pinctrl/pinconf.c index 1892a3794b99..9fb75456824c 100644 --- a/drivers/pinctrl/pinconf.c +++ b/drivers/pinctrl/pinconf.c @@ -205,8 +205,10 @@ int pin_config_group_set(const char *dev_name, const char *pin_group, } EXPORT_SYMBOL(pin_config_group_set); -int pinconf_check_ops(const struct pinconf_ops *ops) +int pinconf_check_ops(struct pinctrl_dev *pctldev) { + const struct pinconf_ops *ops = pctldev->desc->confops; + /* We must be able to read out pin status */ if (!ops->pin_config_get && !ops->pin_config_group_get) return -EINVAL; diff --git a/drivers/pinctrl/pinconf.h b/drivers/pinctrl/pinconf.h index e7dc6165032a..006b77fa737e 100644 --- a/drivers/pinctrl/pinconf.h +++ b/drivers/pinctrl/pinconf.h @@ -13,7 +13,7 @@ #ifdef CONFIG_PINCONF -int pinconf_check_ops(const struct pinconf_ops *ops); +int pinconf_check_ops(struct pinctrl_dev *pctldev); void pinconf_init_device_debugfs(struct dentry *devroot, struct pinctrl_dev *pctldev); int pin_config_get_for_pin(struct pinctrl_dev *pctldev, unsigned pin, @@ -23,7 +23,7 @@ int pin_config_set_for_pin(struct pinctrl_dev *pctldev, unsigned pin, #else -static inline int pinconf_check_ops(const struct pinconf_ops *ops) +static inline int pinconf_check_ops(struct pinctrl_dev *pctldev) { return 0; } diff --git a/drivers/pinctrl/pinmux.c b/drivers/pinctrl/pinmux.c index 3ffa9324ed82..7c3193f7a044 100644 --- a/drivers/pinctrl/pinmux.c +++ b/drivers/pinctrl/pinmux.c @@ -889,8 +889,11 @@ void pinmux_disable(struct pinmux *pmx) } EXPORT_SYMBOL_GPL(pinmux_disable); -int pinmux_check_ops(const struct pinmux_ops *ops) +int pinmux_check_ops(struct pinctrl_dev *pctldev) { + const struct pinmux_ops *ops = pctldev->desc->pmxops; + unsigned selector = 0; + /* Check that we implement required operations */ if (!ops->list_functions || !ops->get_function_name || @@ -899,6 +902,18 @@ int pinmux_check_ops(const struct pinmux_ops *ops) !ops->disable) return -EINVAL; + /* Check that all functions registered have names */ + while (ops->list_functions(pctldev, selector) >= 0) { + const char *fname = ops->get_function_name(pctldev, + selector); + if (!fname) { + pr_err("pinmux ops has no name for function%u\n", + selector); + return -EINVAL; + } + selector++; + } + return 0; } diff --git a/drivers/pinctrl/pinmux.h b/drivers/pinctrl/pinmux.h index 844500b3331b..97f52223fbc2 100644 --- a/drivers/pinctrl/pinmux.h +++ b/drivers/pinctrl/pinmux.h @@ -12,7 +12,7 @@ */ #ifdef CONFIG_PINMUX -int pinmux_check_ops(const struct pinmux_ops *ops); +int pinmux_check_ops(struct pinctrl_dev *pctldev); void pinmux_init_device_debugfs(struct dentry *devroot, struct pinctrl_dev *pctldev); void pinmux_init_debugfs(struct dentry *subsys_root); @@ -21,7 +21,7 @@ void pinmux_unhog_maps(struct pinctrl_dev *pctldev); #else -static inline int pinmux_check_ops(const struct pinmux_ops *ops) +static inline int pinmux_check_ops(struct pinctrl_dev *pctldev) { return 0; }