wlan: prevent kernel crash when fwpath param is retrieved
The fwpath parameter is used to allow userspace to notify the driver
which mode of operation is being started. The driver could handle
writes to the parameter, but could not handle reads. Clean up the
module parameter handling so that all parmeters can be properly
written and read.
Change-Id: Ia2bfffd69d7c02caaa1c94394c66966c2af7cf24
CRs-fixed: 475820
diff --git a/CORE/HDD/src/wlan_hdd_main.c b/CORE/HDD/src/wlan_hdd_main.c
index 8570065..89fa9ca 100644
--- a/CORE/HDD/src/wlan_hdd_main.c
+++ b/CORE/HDD/src/wlan_hdd_main.c
@@ -144,7 +144,11 @@
/* the Android framework expects this param even though we don't use it */
#define BUF_LEN 20
-static char fwpath[BUF_LEN];
+static char fwpath_buffer[BUF_LEN];
+static struct kparam_string fwpath = {
+ .string = fwpath_buffer,
+ .maxlen = BUF_LEN,
+};
#ifndef MODULE
static int wlan_hdd_inited;
#endif
@@ -5537,8 +5541,7 @@
static int fwpath_changed_handler(const char *kmessage,
struct kernel_param *kp)
{
- /* nothing to do when driver is DLKM */
- return 0;
+ return param_set_copystring(kmessage, kp);
}
static int con_mode_handler(const char *kmessage,
@@ -5549,18 +5552,18 @@
#else /* #ifdef MODULE */
/**---------------------------------------------------------------------------
- \brief fwpath_changed_handler() - Handler Function
+ \brief kickstart_driver
- This is the driver entry point
+ This is the driver entry point
- delayed driver initialization when driver is statically linked
- - invoked when module parameter fwpath is modified from userpspace to signal
- initializing the WLAN driver
+ - invoked when module parameter fwpath is modified from userspace to signal
+ initializing the WLAN driver or when con_mode is modified from userspace
+ to signal a switch in operating mode
\return - 0 for success, non zero for failure
--------------------------------------------------------------------------*/
-static int fwpath_changed_handler(const char *kmessage,
- struct kernel_param *kp)
+static int kickstart_driver(void)
{
int ret_status;
@@ -5571,9 +5574,9 @@
}
hdd_driver_exit();
-
+
msleep(200);
-
+
ret_status = hdd_driver_init();
wlan_hdd_inited = ret_status ? 0 : 1;
return ret_status;
@@ -5581,26 +5584,45 @@
/**---------------------------------------------------------------------------
+ \brief fwpath_changed_handler() - Handler Function
+
+ Handle changes to the fwpath parameter
+
+ \return - 0 for success, non zero for failure
+
+ --------------------------------------------------------------------------*/
+static int fwpath_changed_handler(const char *kmessage,
+ struct kernel_param *kp)
+{
+ int ret;
+
+ ret = param_set_copystring(kmessage, kp);
+ if (0 == ret)
+ ret = kickstart_driver();
+ return ret;
+}
+
+/**---------------------------------------------------------------------------
+
\brief con_mode_handler() -
Handler function for module param con_mode when it is changed by userspace
Dynamically linked - do nothing
Statically linked - exit and init driver, as in rmmod and insmod
- \param -
+ \param -
- \return -
+ \return -
--------------------------------------------------------------------------*/
-static int con_mode_handler(const char *kmessage,
- struct kernel_param *kp)
+static int con_mode_handler(const char *kmessage, struct kernel_param *kp)
{
- int ret = param_set_int(kmessage, kp);
+ int ret;
- if (ret)
- return ret;
-
- return fwpath_changed_handler(kmessage, kp);
+ ret = param_set_int(kmessage, kp);
+ if (0 == ret)
+ ret = kickstart_driver();
+ return ret;
}
#endif /* #ifdef MODULE */
@@ -6032,5 +6054,5 @@
module_param_call(con_mode, con_mode_handler, param_get_int, &con_mode,
S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
-module_param_call(fwpath, fwpath_changed_handler, param_get_string, fwpath,
+module_param_call(fwpath, fwpath_changed_handler, param_get_string, &fwpath,
S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);