[PATCH] Fix snd-usb-audio in 32-bit compat environment
I'm getting oopses with snd-usb-audio in 32-bit compat environments:
control_compat.c:get_ctl_type() doesn't initialize 'info', so
'itemlist[uinfo->value.enumerated.item]' in
usbmixer.c:mixer_ctl_selector_info() might access random memory (The 'if
((int)uinfo->value.enumerated.item >= cval->max)' doesn't fix all problems
because of the unsigned -> signed conversion.)
Signed-off-by: Juergen Kreileder <jk@blackdown.de>
Cc: Jaroslav Kysela <perex@suse.cz>
Acked-by: Takashi Iwai <tiwai@suse.de>
Cc: Greg KH <greg@kroah.com>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/sound/core/control_compat.c b/sound/core/control_compat.c
index 418c6d4..a529b62 100644
--- a/sound/core/control_compat.c
+++ b/sound/core/control_compat.c
@@ -167,7 +167,7 @@
int *countp)
{
struct snd_kcontrol *kctl;
- struct snd_ctl_elem_info info;
+ struct snd_ctl_elem_info *info;
int err;
down_read(&card->controls_rwsem);
@@ -176,13 +176,19 @@
up_read(&card->controls_rwsem);
return -ENXIO;
}
- info.id = *id;
- err = kctl->info(kctl, &info);
+ info = kzalloc(sizeof(*info), GFP_KERNEL);
+ if (info == NULL) {
+ up_read(&card->controls_rwsem);
+ return -ENOMEM;
+ }
+ info->id = *id;
+ err = kctl->info(kctl, info);
up_read(&card->controls_rwsem);
if (err >= 0) {
- err = info.type;
- *countp = info.count;
+ err = info->type;
+ *countp = info->count;
}
+ kfree(info);
return err;
}