Auto merge of #14623 - DominoTree:master, r=emilio

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Add check for bad ports to http_fetch(), return NetworkError::Internal if bad port/schema combination is seen.

Test added

---
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- [x] `./mach build -d` does not report any errors
- [x] `./mach test-tidy` does not report any errors
- [x] These changes fix #14514 (github issue number if applicable).

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- [x] There are tests for these changes OR

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components/net/fetch/methods.rs

@@ -143,6 +143,18 @@ pub fn main_fetch(request: Rc<Request>,
 
     // Step 5
     // TODO this step (CSP port/content blocking)
+    if let Some(port) = request.url().port() {
+        let is_ftp = request.url().scheme() == "ftp" && (port == 20 || port == 21);
+        static BAD_PORTS: [u16; 64] = [1, 7, 9, 11, 13, 15, 17, 19, 20, 21, 22, 23, 25, 37, 42,
+                                       43, 53, 77, 79, 87, 95, 101, 102, 103, 104, 109, 110, 111,
+                                       113, 115, 117, 119, 123, 135, 139, 143, 179, 389, 465, 512,
+                                       513, 514, 515, 526, 530, 531, 532, 540, 556, 563, 587, 601,
+                                       636, 993, 995, 2049, 3659, 4045, 6000, 6665, 6666, 6667,
+                                       6668, 6669];
+        if !is_ftp && BAD_PORTS.binary_search(&port).is_ok() {
+            response = Some(Response::network_error(NetworkError::Internal("Request attempted on bad port".into())));
+        }
+    }
 
     // Step 6
     // TODO this step (referrer policy)