[Spice-devel] [PATCH spice-server 3/3] reds: Fix one case parsing invalid codec string

[Frediano Ziglio]

In case we pass something like "spice:mjpeg$%*" the last part is
ignore making the string parse correctly.
A single pair should end by either string terminator or pair terminator.

Signed-off-by: Frediano Ziglio <fziglio at redhat.com>
---
 server/reds.c                      | 10 +++++++---
 server/tests/test-codecs-parsing.c |  6 ++++++
 2 files changed, 13 insertions(+), 3 deletions(-)

Maybe for future extension we should support also syntaxes
like "encoder:codec:whatsoever" ?

diff --git a/server/reds.c b/server/reds.c
index 4d343b25..03c2bfa1 100644
--- a/server/reds.c
+++ b/server/reds.c
@@ -3555,10 +3555,14 @@ static const char* parse_video_codecs(const char *codecs, char **encoder,
     }
     int n;
     *encoder = *codec = NULL;
-    if (sscanf(codecs, "%m[0-9a-zA-Z_]:%m[0-9a-zA-Z_]%n", encoder, codec, &n) != 2) {
-        return codecs + strcspn(codecs, ";");
+    if (sscanf(codecs, "%m[0-9a-zA-Z_]:%m[0-9a-zA-Z_]%n", encoder, codec, &n) == 2) {
+        // this avoids accepting "encoder:codec" followed by garbage like "$%*"
+        if (codecs[n] != ';' && codecs[n] != '\0') {
+            free(*codec);
+            *codec = NULL;
+        }
     }
-    return codecs + n;
+    return codecs + strcspn(codecs, ";");
 }
 
 static void reds_set_video_codecs_from_string(RedsState *reds, const char *codecs)
diff --git a/server/tests/test-codecs-parsing.c b/server/tests/test-codecs-parsing.c
index 860a575e..7998501c 100644
--- a/server/tests/test-codecs-parsing.c
+++ b/server/tests/test-codecs-parsing.c
@@ -115,6 +115,12 @@ static void codecs_bad(void)
             G_LOG_LEVEL_WARNING,
             "*spice: invalid encoder:codec value*",
             TRUE,
+        },{
+            // invalid character in codec
+            "spice:mjpeg&",
+            G_LOG_LEVEL_WARNING,
+            "*spice: invalid encoder:codec value*",
+            TRUE,
         },
 #if !defined(HAVE_GSTREAMER_1_0) && !defined(HAVE_GSTREAMER_0_10)
         {
-- 
2.17.1