Driver core: change add_uevent_var to use a struct

This changes the uevent buffer functions to use a struct instead of a
long list of parameters. It does no longer require the caller to do the
proper buffer termination and size accounting, which is currently wrong
in some places. It fixes a known bug where parts of the uevent
environment are overwritten because of wrong index calculations.

Many thanks to Mathieu Desnoyers for finding bugs and improving the
error handling.

Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 4 insertions, 10 deletions

diff --git a/drivers/s390/crypto/ap_bus.c b/drivers/s390/crypto/ap_bus.c
index 90bd220..e997130 100644
--- a/drivers/s390/crypto/ap_bus.c
+++ b/drivers/s390/crypto/ap_bus.c
@@ -458,28 +458,22 @@ static int ap_bus_match(struct device *dev, struct device_driver *drv)
  * uevent function for AP devices. It sets up a single environment
  * variable DEV_TYPE which contains the hardware device type.
  */
-static int ap_uevent (struct device *dev, char **envp, int num_envp,
-		       char *buffer, int buffer_size)
+static int ap_uevent (struct device *dev, struct kobj_uevent_env *env)
 {
 	struct ap_device *ap_dev = to_ap_dev(dev);
-	int retval = 0, length = 0, i = 0;
+	int retval = 0;
 
 	if (!ap_dev)
 		return -ENODEV;
 
 	/* Set up DEV_TYPE environment variable. */
-	retval = add_uevent_var(envp, num_envp, &i,
-				buffer, buffer_size, &length,
-				"DEV_TYPE=%04X", ap_dev->device_type);
+	retval = add_uevent_var(env, "DEV_TYPE=%04X", ap_dev->device_type);
 	if (retval)
 		return retval;
 
 	/* Add MODALIAS= */
-	retval = add_uevent_var(envp, num_envp, &i,
-				buffer, buffer_size, &length,
-				"MODALIAS=ap:t%02X", ap_dev->device_type);
+	retval = add_uevent_var(env, "MODALIAS=ap:t%02X", ap_dev->device_type);
 
-	envp[i] = NULL;
 	return retval;
 }