Merge pull request #5600 from sylvestre/fuzz-echo

Fuzz the echo command

.github/workflows/fuzzing.yml

@@ -46,6 +46,7 @@ jobs:
           - { name: fuzz_date, should_pass: false }
           - { name: fuzz_expr, should_pass: true }
           - { name: fuzz_printf, should_pass: false }
+          - { name: fuzz_echo, should_pass: false }
           - { name: fuzz_parse_glob, should_pass: true }
           - { name: fuzz_parse_size, should_pass: true }
           - { name: fuzz_parse_time, should_pass: true }

fuzz/Cargo.toml

@@ -17,6 +17,7 @@ uu_date = { path = "../src/uu/date/" }
 uu_test = { path = "../src/uu/test/" }
 uu_expr = { path = "../src/uu/expr/" }
 uu_printf = { path = "../src/uu/printf/" }
+uu_echo = { path = "../src/uu/echo/" }
 
 
 # Prevent this from interfering with workspaces
@@ -35,6 +36,12 @@ path = "fuzz_targets/fuzz_printf.rs"
 test = false
 doc = false
 
+[[bin]]
+name = "fuzz_echo"
+path = "fuzz_targets/fuzz_echo.rs"
+test = false
+doc = false
+
 [[bin]]
 name = "fuzz_expr"
 path = "fuzz_targets/fuzz_expr.rs"

fuzz/fuzz_targets/fuzz_echo.rs

@@ -0,0 +1,89 @@
+#![no_main]
+use libfuzzer_sys::fuzz_target;
+use uu_echo::uumain;
+
+use rand::prelude::SliceRandom;
+use rand::Rng;
+use std::ffi::OsString;
+
+mod fuzz_common;
+use crate::fuzz_common::CommandResult;
+use crate::fuzz_common::{
+    compare_result, generate_and_run_uumain, generate_random_string, run_gnu_cmd,
+};
+
+static CMD_PATH: &str = "echo";
+
+fn generate_echo() -> String {
+    let mut rng = rand::thread_rng();
+    let mut echo_str = String::new();
+
+    // Randomly decide whether to include options
+    let include_n = rng.gen_bool(0.1); // 10% chance
+    let include_e = rng.gen_bool(0.1); // 10% chance
+    let include_E = rng.gen_bool(0.1); // 10% chance
+
+    if include_n {
+        echo_str.push_str("-n ");
+    }
+    if include_e {
+        echo_str.push_str("-e ");
+    }
+    if include_E {
+        echo_str.push_str("-E ");
+    }
+
+    // Add a random string
+    echo_str.push_str(&generate_random_string(rng.gen_range(1..=10)));
+
+    // Include escape sequences if -e is enabled
+    if include_e {
+        // Add a 10% chance of including an escape sequence
+        if rng.gen_bool(0.1) {
+            echo_str.push_str(&generate_escape_sequence(&mut rng));
+        }
+    }
+
+    echo_str
+}
+
+fn generate_escape_sequence(rng: &mut impl Rng) -> String {
+    let escape_sequences = [
+        "\\\\", "\\a", "\\b", "\\c", "\\e", "\\f", "\\n", "\\r", "\\t", "\\v", "\\0NNN", "\\xHH",
+    ];
+    // \0NNN and \xHH need more work
+    escape_sequences.choose(rng).unwrap().to_string()
+}
+
+fuzz_target!(|_data: &[u8]| {
+    let echo_input = generate_echo();
+    let mut args = vec![OsString::from("echo")];
+    args.extend(echo_input.split_whitespace().map(OsString::from));
+    let rust_result = generate_and_run_uumain(&args, uumain);
+
+    let gnu_result = match run_gnu_cmd(CMD_PATH, &args[1..], false) {
+        Ok(result) => result,
+        Err(error_result) => {
+            eprintln!("Failed to run GNU command:");
+            eprintln!("Stderr: {}", error_result.stderr);
+            eprintln!("Exit Code: {}", error_result.exit_code);
+            CommandResult {
+                stdout: String::new(),
+                stderr: error_result.stderr,
+                exit_code: error_result.exit_code,
+            }
+        }
+    };
+
+    compare_result(
+        "echo",
+        &format!("{:?}", &args[1..]),
+        &rust_result.stdout,
+        &gnu_result.stdout,
+        &rust_result.stderr,
+        &gnu_result.stderr,
+        rust_result.exit_code,
+        gnu_result.exit_code,
+        true,
+    );
+});