If we successfully decompress an HTTP body, return immediately.

This prevents us from calling
allowed_anonymous_connection_compression_method() on the unused
guessed method (if any), and rejecting something that was already
safe to use.

1 files changed, 18 insertions, 6 deletions

diff --git a/src/or/directory.c b/src/or/directory.c
index b6121d80d8..ac40e54ceb 100644
--- a/src/or/directory.c
+++ b/src/or/directory.c
@@ -2255,9 +2255,15 @@ dir_client_decompress_response_body(char **bodyp, size_t *bodylenp,
     goto done;
   }
 
-  if (tor_compress_supports_method(compression))
+  if (tor_compress_supports_method(compression)) {
     tor_uncompress(&new_body, &new_len, body, body_len, compression,
                    !allow_partial, LOG_PROTOCOL_WARN);
+    if (new_body) {
+      /* We succeeded with the declared compression method. Great! */
+      rv = 0;
+      goto done;
+    }
+  }
 
   /* Okay, if that didn't work, and we think that it was compressed
    * differently, try that. */
@@ -2268,7 +2274,7 @@ dir_client_decompress_response_body(char **bodyp, size_t *bodylenp,
     goto done;
   }
 
-  if (!new_body && tor_compress_supports_method(guessed) &&
+  if (tor_compress_supports_method(guessed) &&
       compression != guessed) {
     tor_uncompress(&new_body, &new_len, body, body_len, guessed,
                    !allow_partial, LOG_INFO);
@@ -2286,13 +2292,19 @@ dir_client_decompress_response_body(char **bodyp, size_t *bodylenp,
     rv = -1;
     goto done;
   }
+
+ done:
   if (new_body) {
-    tor_free(*bodyp);
-    *bodyp = new_body;
-    *bodylenp = new_len;
+    if (rv == 0) {
+      /* success! */
+      tor_free(*bodyp);
+      *bodyp = new_body;
+      *bodylenp = new_len;
+    } else {
+      tor_free(new_body);
+    }
   }
 
- done:
   return rv;
 }