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>


diff --git a/drivers/pci/hotplug.c b/drivers/pci/hotplug.c
index 1c97e7d..2b5352a 100644
--- a/drivers/pci/hotplug.c
+++ b/drivers/pci/hotplug.c
@@ -3,12 +3,9 @@
 #include <linux/module.h>
 #include "pci.h"
 
-int pci_uevent(struct device *dev, char **envp, int num_envp,
-	       char *buffer, int buffer_size)
+int pci_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
 	struct pci_dev *pdev;
-	int i = 0;
-	int length = 0;
 
 	if (!dev)
 		return -ENODEV;
@@ -17,37 +14,24 @@
 	if (!pdev)
 		return -ENODEV;
 
-	if (add_uevent_var(envp, num_envp, &i,
-			   buffer, buffer_size, &length,
-			   "PCI_CLASS=%04X", pdev->class))
+	if (add_uevent_var(env, "PCI_CLASS=%04X", pdev->class))
 		return -ENOMEM;
 
-	if (add_uevent_var(envp, num_envp, &i,
-			   buffer, buffer_size, &length,
-			   "PCI_ID=%04X:%04X", pdev->vendor, pdev->device))
+	if (add_uevent_var(env, "PCI_ID=%04X:%04X", pdev->vendor, pdev->device))
 		return -ENOMEM;
 
-	if (add_uevent_var(envp, num_envp, &i,
-			   buffer, buffer_size, &length,
-			   "PCI_SUBSYS_ID=%04X:%04X", pdev->subsystem_vendor,
+	if (add_uevent_var(env, "PCI_SUBSYS_ID=%04X:%04X", pdev->subsystem_vendor,
 			   pdev->subsystem_device))
 		return -ENOMEM;
 
-	if (add_uevent_var(envp, num_envp, &i,
-			   buffer, buffer_size, &length,
-			   "PCI_SLOT_NAME=%s", pci_name(pdev)))
+	if (add_uevent_var(env, "PCI_SLOT_NAME=%s", pci_name(pdev)))
 		return -ENOMEM;
 
-	if (add_uevent_var(envp, num_envp, &i,
-			   buffer, buffer_size, &length,
-			   "MODALIAS=pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02x",
+	if (add_uevent_var(env, "MODALIAS=pci:v%08Xd%08Xsv%08Xsd%08Xbc%02Xsc%02Xi%02x",
 			   pdev->vendor, pdev->device,
 			   pdev->subsystem_vendor, pdev->subsystem_device,
 			   (u8)(pdev->class >> 16), (u8)(pdev->class >> 8),
 			   (u8)(pdev->class)))
 		return -ENOMEM;
-
-	envp[i] = NULL;
-
 	return 0;
 }