ALSA: core: fix buffer overflow in snd_info_get_line()
snd_info_get_line() documents that its last parameter must be one
less than the buffer size, but this API design guarantees that
(literally) every caller gets it wrong.
Just change this parameter to have its obvious meaning.
Reported-by: Tommi Rantala <tt.rantala@gmail.com>
Cc: <stable@vger.kernel.org> # v2.2.26+
Signed-off-by: Clemens Ladisch <clemens@ladisch.de>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
diff --git a/sound/core/info.c b/sound/core/info.c
index 051d55b..9f404e9 100644
--- a/sound/core/info.c
+++ b/sound/core/info.c
@@ -684,7 +684,7 @@
* snd_info_get_line - read one line from the procfs buffer
* @buffer: the procfs buffer
* @line: the buffer to store
- * @len: the max. buffer size - 1
+ * @len: the max. buffer size
*
* Reads one line from the buffer and stores the string.
*
@@ -704,7 +704,7 @@
buffer->stop = 1;
if (c == '\n')
break;
- if (len) {
+ if (len > 1) {
len--;
*line++ = c;
}