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, 10 insertions, 23 deletions

diff --git a/sound/aoa/soundbus/core.c b/sound/aoa/soundbus/core.c
index 64d163914335..f84f3e505788 100644
--- a/sound/aoa/soundbus/core.c
+++ b/sound/aoa/soundbus/core.c
@@ -56,13 +56,12 @@ static int soundbus_probe(struct device *dev)
 }
 
 
-static int soundbus_uevent(struct device *dev, char **envp, int num_envp,
-                           char *buffer, int buffer_size)
+static int soundbus_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
         struct soundbus_dev * soundbus_dev;
         struct of_device * of;
         const char *compat;
-        int retval = 0, i = 0, length = 0;
+        int retval = 0;
         int cplen, seen = 0;
 
         if (!dev)
@@ -75,15 +74,11 @@ static int soundbus_uevent(struct device *dev, char **envp, int num_envp,
         of = &soundbus_dev->ofdev;
 
         /* stuff we want to pass to /sbin/hotplug */
-        retval = add_uevent_var(envp, num_envp, &i,
-                                buffer, buffer_size, &length,
-                                "OF_NAME=%s", of->node->name);
+        retval = add_uevent_var(env, "OF_NAME=%s", of->node->name);
         if (retval)
                 return retval;
 
-        retval = add_uevent_var(envp, num_envp, &i,
-                                buffer, buffer_size, &length,
-                                "OF_TYPE=%s", of->node->type);
+        retval = add_uevent_var(env, "OF_TYPE=%s", of->node->type);
         if (retval)
                 return retval;
 
@@ -93,27 +88,19 @@ static int soundbus_uevent(struct device *dev, char **envp, int num_envp,
 
         compat = of_get_property(of->node, "compatible", &cplen);
         while (compat && cplen > 0) {
-                int tmp = length;
-                retval = add_uevent_var(envp, num_envp, &i,
-                                        buffer, buffer_size, &length,
-                                        "OF_COMPATIBLE_%d=%s", seen, compat);
+                int tmp = env->buflen;
+                retval = add_uevent_var(env, "OF_COMPATIBLE_%d=%s", seen, compat);
                 if (retval)
                         return retval;
-                compat += length - tmp;
-                cplen -= length - tmp;
+                compat += env->buflen - tmp;
+                cplen -= env->buflen - tmp;
                 seen += 1;
         }
 
-        retval = add_uevent_var(envp, num_envp, &i,
-                                buffer, buffer_size, &length,
-                                "OF_COMPATIBLE_N=%d", seen);
+        retval = add_uevent_var(env, "OF_COMPATIBLE_N=%d", seen);
         if (retval)
                 return retval;
-        retval = add_uevent_var(envp, num_envp, &i,
-                                buffer, buffer_size, &length,
-                                "MODALIAS=%s", soundbus_dev->modalias);
-
-        envp[i] = NULL;
+        retval = add_uevent_var(env, "MODALIAS=%s", soundbus_dev->modalias);
 
         return retval;
 }