Update trust-dns to fix possible panic (#975)

Our fuzz tests trigger a panic in trust-dns when resolving names through
the search path (i.e., in `/etc/hosts`) as described in
bluejekyll/trust-dns#1447.

This change patches our trust-dns dependencies to use include
bluejekyll/trust-dns#6dfc6713 (which has not yet been released to
crates.io)

Fixes https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=33123

Author: olix0r

Cargo.lock

@@ -2353,9 +2353,8 @@ dependencies = [
 
 [[package]]
 name = "trust-dns-proto"
-version = "0.20.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "98a0381b2864c2978db7f8e17c7b23cca5a3a5f99241076e13002261a8ecbabd"
+version = "0.20.1"
+source = "git+https://github.com/bluejekyll/trust-dns?branch=main#6dfc6713fa4448bca3c691aab366a4bae683df65"
 dependencies = [
  "async-trait",
  "cfg-if",
@@ -2371,15 +2370,15 @@ dependencies = [
  "rand",
  "smallvec",
  "thiserror",
+ "tinyvec",
  "tokio",
  "url",
 ]
 
 [[package]]
 name = "trust-dns-resolver"
-version = "0.20.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3072d18c10bd621cb00507d59cfab5517862285c353160366e37fbf4c74856e4"
+version = "0.20.1"
+source = "git+https://github.com/bluejekyll/trust-dns?branch=main#6dfc6713fa4448bca3c691aab366a4bae683df65"
 dependencies = [
  "cfg-if",
  "futures-util",

Cargo.toml

@@ -63,4 +63,6 @@ debug = false
 debug = false
 
 [patch.crates-io]
+trust-dns-proto = { git = "https://github.com/bluejekyll/trust-dns", branch = "main" }
+trust-dns-resolver = { git = "https://github.com/bluejekyll/trust-dns", branch = "main" }
 webpki = { git = "https://github.com/linkerd/webpki", branch = "cert-dns-names-0.21" }

deny.toml

@@ -53,6 +53,7 @@ unknown-registry = "deny"
 unknown-git = "deny"
 allow-registry = ["https://github.com/rust-lang/crates.io-index"]
 allow-git = [
+    "https://github.com/bluejekyll/trust-dns",
     "https://github.com/hawkw/tokio-trace",
 ]
 

linkerd/dns/fuzz/Cargo.toml

@@ -29,3 +29,7 @@ path = "fuzz_targets/fuzz_target_1.rs"
 test = false
 doc = false
 required-features = ["fuzzing"]
+
+[patch.crates-io]
+trust-dns-proto = { git = "https://github.com/bluejekyll/trust-dns", branch = "main" }
+trust-dns-resolver = { git = "https://github.com/bluejekyll/trust-dns", branch = "main" }