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, 2 insertions, 9 deletions

diff --git a/drivers/firewire/fw-device.c b/drivers/firewire/fw-device.c
index 2b6586341635..56681b3b297b 100644
--- a/drivers/firewire/fw-device.c
+++ b/drivers/firewire/fw-device.c
@@ -130,23 +130,16 @@ static int get_modalias(struct fw_unit *unit, char *buffer, size_t buffer_size)
 }
 
 static int
-fw_unit_uevent(struct device *dev, char **envp, int num_envp,
-               char *buffer, int buffer_size)
+fw_unit_uevent(struct device *dev, struct kobj_uevent_env *env)
 {
         struct fw_unit *unit = fw_unit(dev);
         char modalias[64];
-        int length = 0;
-        int i = 0;
 
         get_modalias(unit, modalias, sizeof(modalias));
 
-        if (add_uevent_var(envp, num_envp, &i,
-                           buffer, buffer_size, &length,
-                           "MODALIAS=%s", modalias))
+        if (add_uevent_var(env, "MODALIAS=%s", modalias))
                 return -ENOMEM;
 
-        envp[i] = NULL;
-
         return 0;
 }