Fuzz for compatibility with bincode v1 (#498)

* Fuzz for compatibility with bincode v1

* Make AllTypes recursive

* Revert round trip test (add recursion to it too)

* Update fuzzer lockfile

* Adjust compat fuzzer to be stricter

* data doesn't need to be a &&[u8]

fuzz/Cargo.lock

@@ -8,6 +8,15 @@ version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "510c76ecefdceada737ea728f4f9a84bd2e1ef29f1ba555e560940fe279954de"
 
+[[package]]
+name = "bincode"
+version = "1.3.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1f45e9417d87227c7a56d22e471c6206462cba514c7590c09aff4cf6d1ddcad"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "bincode"
 version = "2.0.0-beta.2"
@@ -19,8 +28,10 @@ dependencies = [
 name = "bincode-fuzz"
 version = "0.0.0"
 dependencies = [
- "bincode",
+ "bincode 1.3.3",
+ "bincode 2.0.0-beta.2",
  "libfuzzer-sys",
+ "serde",
 ]
 
 [[package]]
@@ -54,7 +65,62 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "da32515d9f6e6e489d7bc9d84c71b060db7247dc035bbe44eac88cf87486d8d5"
 
 [[package]]
-name = "virtue"
+name = "proc-macro2"
-version = "0.0.4"
+version = "1.0.36"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f0e85ed1066abcc0ea331cce3ce83cccf30ae9900529ca46f353b22ca79b56b8"
+checksum = "c7342d5883fbccae1cc37a2353b09c87c9b0f3afd73f5fb9bba687a1f733b029"
+dependencies = [
+ "unicode-xid",
+]
+
+[[package]]
+name = "quote"
+version = "1.0.15"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "864d3e96a899863136fc6e99f3d7cae289dafe43bf2c5ac19b70df7210c0a145"
+dependencies = [
+ "proc-macro2",
+]
+
+[[package]]
+name = "serde"
+version = "1.0.135"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2cf9235533494ea2ddcdb794665461814781c53f19d87b76e571a1c35acbad2b"
+dependencies = [
+ "serde_derive",
+]
+
+[[package]]
+name = "serde_derive"
+version = "1.0.135"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8dcde03d87d4c973c04be249e7d8f0b35db1c848c487bd43032808e59dd8328d"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "syn"
+version = "1.0.86"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8a65b3f4ffa0092e9887669db0eae07941f023991ab58ea44da8fe8e2d511c6b"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "unicode-xid",
+]
+
+[[package]]
+name = "unicode-xid"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8ccb82d61f80a663efe1f787a51b16b5a51e3314d6ac365b08639f52387b33f3"
+
+[[package]]
+name = "virtue"
+version = "0.0.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "757cfbfe0d17ee6f22fe97e536d463047d451b47cf9d11e2b7d1398b0ef274dd"

fuzz/Cargo.toml

@@ -10,6 +10,8 @@ cargo-fuzz = true
 
 [dependencies]
 libfuzzer-sys = "0.4"
+bincodev1 = {package = "bincode", version = "1.3.3"}
+serde = { version = "1.0.135", features = ["derive"] }
 
 [dependencies.bincode]
 path = ".."
@@ -23,3 +25,9 @@ name = "roundtrip"
 path = "fuzz_targets/roundtrip.rs"
 test = false
 doc = false
+
+[[bin]]
+name = "compat"
+path = "fuzz_targets/compat.rs"
+test = false
+doc = false

fuzz/fuzz_targets/compat.rs

@@ -0,0 +1,55 @@
+#![no_main]
+use libfuzzer_sys::fuzz_target;
+
+use std::collections::{BTreeMap, BTreeSet, VecDeque};
+use std::ffi::CString;
+use std::net::{IpAddr, Ipv4Addr, Ipv6Addr, SocketAddr, SocketAddrV4, SocketAddrV6};
+use std::num::{NonZeroI128, NonZeroI32, NonZeroU128, NonZeroU32};
+use std::path::PathBuf;
+use std::time::{Duration, SystemTime};
+
+#[derive(bincode::Decode, bincode::Encode, PartialEq, Debug, serde::Serialize, serde::Deserialize, Eq, PartialOrd, Ord)]
+enum AllTypes {
+    BTreeMap(BTreeMap<u8, AllTypes>),
+    BTreeSet(BTreeSet<AllTypes>),
+    VecDeque(VecDeque<AllTypes>),
+    Vec(Vec<u8>),
+    String(String),
+    Box(Box<u8>),
+    BoxSlice(Box<[u8]>),
+    CString(CString),
+    SystemTime(SystemTime),
+    Duration(Duration),
+    PathBuf(PathBuf),
+    IpAddr(IpAddr),
+    Ipv4Addr(Ipv4Addr),
+    Ipv6Addr(Ipv6Addr),
+    SocketAddr(SocketAddr),
+    SocketAddrV4(SocketAddrV4),
+    SocketAddrV6(SocketAddrV6),
+    NonZeroU32(NonZeroU32),
+    NonZeroI32(NonZeroI32),
+    NonZeroU128(NonZeroU128),
+    NonZeroI128(NonZeroI128),
+    I128(i128),
+    I8(i8),
+    U128(u128),
+    U8(u8),
+    // Cow(Cow<'static, [u8]>), Blocked, see comment on decode
+}
+
+fuzz_target!(|data: &[u8]| {
+    let config = bincode::config::legacy().with_limit::<1024>();
+    #[allow(deprecated)]
+    let mut configv1 = bincodev1::config();
+    configv1.limit(1024);
+    let bincode_v1: Result<AllTypes, _> = configv1.deserialize(data);
+    let bincode_v2: Result<(AllTypes, _), _> = bincode::decode_from_slice(data, config);
+
+    if bincode_v1.as_ref().ok() != bincode_v2.as_ref().ok().map(|x| &x.0) {
+        println!("Bytes:      {:?}", data);
+        println!("Bincode V1: {:?}", bincode_v1);
+        println!("Bincode V2: {:?}", bincode_v2);
+        panic!("failed equality check");
+    }
+});

fuzz/fuzz_targets/roundtrip.rs

@@ -15,13 +15,13 @@ enum AllTypes {
     BTreeMap(BTreeMap<u8, u8>),
     HashMap(HashMap<u8, u8>),
     BTreeSet(BTreeSet<u8>),
-    VecDeque(VecDeque<u8>),
+    VecDeque(VecDeque<AllTypes>),
-    Vec(Vec<u8>),
+    Vec(Vec<AllTypes>),
     String(String),
-    Box(Box<u8>),
+    Box(Box<AllTypes>),
-    BoxSlice(Box<[u8]>),
+    BoxSlice(Box<[AllTypes]>),
-    Rc(Rc<u8>),
+    Rc(Rc<AllTypes>),
-    Arc(Arc<u8>),
+    Arc(Arc<AllTypes>),
     CString(CString),
     SystemTime(SystemTime),
     Duration(Duration),