[ALSA] Fix re-use of va_list

The va_list is designed to be used only once.  The current code
may pass va_list arguments multiple times and may cause Oops.
Copy/release the arguments temporarily to avoid this problem.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Jaroslav Kysela <perex@suse.cz>

1 files changed, 4 insertions, 1 deletions

diff --git a/sound/core/info.c b/sound/core/info.c
index e43662b33f16..0b4aab3225e5 100644
--- a/sound/core/info.c
+++ b/sound/core/info.c
@@ -120,7 +120,10 @@ int snd_iprintf(struct snd_info_buffer *buffer, char *fmt,...)
         len = buffer->len - buffer->size;
         va_start(args, fmt);
         for (;;) {
-                res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, args);
+                va_list ap;
+                va_copy(ap, args);
+                res = vsnprintf(buffer->buffer + buffer->curr, len, fmt, ap);
+                va_end(ap);
                 if (res < len)
                         break;
                 err = resize_info_buffer(buffer, buffer->len + PAGE_SIZE);