[PATCH 4.4 099/138] ALSA: hda: Fix krealloc() with __GFP_ZERO usage

Greg Kroah-Hartman
2016-08-18T14:05:24Z

From: Takashi Iwai <tiwai@suse.de>

commit 33baefe5e72f17a6df378e48196cd8cada11deec upstream.

krealloc() doesn't work always properly with __GFP_ZERO flag as
expected. For clearing the reallocated area, we need to clear
explicitly instead.

Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
sound/hda/array.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

--- a/sound/hda/array.c
+++ b/sound/hda/array.c
@@ -21,13 +21,15 @@ void *snd_array_new(struct snd_array *ar
return NULL;
if (array->used >= array->alloced) {
int num = array->alloced + array->alloc_align;
+ int oldsize = array->alloced * array->elem_size;
int size = (num + 1) * array->elem_size;
void *nlist;
if (snd_BUG_ON(num >= 4096))
return NULL;
- nlist = krealloc(array->list, size, GFP_KERNEL | __GFP_ZERO);
+ nlist = krealloc(array->list, size, GFP_KERNEL);
if (!nlist)
return NULL;
+ memset(nlist + oldsize, 0, size - oldsize);
array->list = nlist;
array->alloced = num;
}