ALSA: hda - Fix and neaten print_nid_path/debug_badness

print_nid_path has a possible buffer overflow if
struct nid_path.path values are > 256.

Avoid this and neaten the output to remove the leading ':'

Neaten debug_badness to always verify arguments.

Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>

1 files changed, 11 insertions, 9 deletions

diff --git a/sound/pci/hda/hda_generic.c b/sound/pci/hda/hda_generic.c
index a24c7b28b000..b956449ddada 100644
--- a/sound/pci/hda/hda_generic.c
+++ b/sound/pci/hda/hda_generic.c
@@ -350,16 +350,16 @@ static void print_nid_path(struct hda_codec *codec,
                            const char *pfx, struct nid_path *path)
 {
         char buf[40];
+        char *pos = buf;
         int i;
 
+        *pos = 0;
+        for (i = 0; i < path->depth; i++)
+                pos += scnprintf(pos, sizeof(buf) - (pos - buf), "%s%02x",
+                                 pos != buf ? ":" : "",
+                                 path->path[i]);
 
-        buf[0] = 0;
-        for (i = 0; i < path->depth; i++) {
-                char tmp[4];
-                sprintf(tmp, ":%02x", path->path[i]);
-                strlcat(buf, tmp, sizeof(buf));
-        }
-        codec_dbg(codec, "%s path: depth=%d %s\n", pfx, path->depth, buf);
+        codec_dbg(codec, "%s path: depth=%d '%s'\n", pfx, path->depth, buf);
 }
 
 /* called recursively */
@@ -1700,9 +1700,11 @@ static int fill_and_eval_dacs(struct hda_codec *codec,
 #define DEBUG_BADNESS
 
 #ifdef DEBUG_BADNESS
-#define debug_badness(fmt, args...)     codec_dbg(codec, fmt, ##args)
+#define debug_badness(fmt, ...)                                         \
+        codec_dbg(codec, fmt, ##__VA_ARGS__)
 #else
-#define debug_badness(...)
+#define debug_badness(fmt, ...)                                         \
+        do { if (0) codec_dbg(codec, fmt, ##__VA_ARGS__); } while (0)
 #endif
 
 #ifdef DEBUG_BADNESS