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sylvestresylvestre
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add a github check for programs not using traversal
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‎.github/workflows/CICD.yml‎

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- name: Lint with SELinux
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run: lima bash -c "cd work && cargo clippy --all-targets --features 'feat_selinux' -- -D warnings"
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test_safe_traversal:
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name: Safe Traversal Security Check
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runs-on: ubuntu-latest
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needs: [ min_version, deps ]
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steps:
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- uses: actions/checkout@v5
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with:
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persist-credentials: false
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- uses: dtolnay/rust-toolchain@stable
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- uses: Swatinem/rust-cache@v2
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- name: Install strace
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run: sudo apt-get update && sudo apt-get install -y strace
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- name: Build utilities with safe traversal
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run: cargo build --release -p uu_rm -p uu_chmod -p uu_chown -p uu_chgrp -p uu_mv -p uu_du
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- name: Run safe traversal verification
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run: ./util/check-safe-traversal.sh
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benchmarks:
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name: Run benchmarks (CodSpeed)
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runs-on: ubuntu-latest

‎.vscode/cSpell.json‎

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"docs/src/release-notes/**",
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"src/uu/*/benches/*.rs",
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"src/uucore/src/lib/features/benchmark.rs",
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"util/check-safe-traversal.sh",
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],
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"enableGlobDot": true,

‎util/check-safe-traversal.sh‎

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#!/bin/bash
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#
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# Check that utilities are using safe traversal (openat family syscalls)
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# to prevent TOCTOU race conditions
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#
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set -e
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SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
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PROJECT_ROOT="$(cd "$SCRIPT_DIR/.." && pwd)"
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TEMP_DIR=$(mktemp -d)
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# Function to exit immediately on error
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fail_immediately() {
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echo "❌ FAILED: $1"
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echo ""
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echo "Debug information available in: $TEMP_DIR/strace_*.log"
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exit 1
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}
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cleanup() {
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rm -rf "$TEMP_DIR"
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}
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trap cleanup EXIT
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echo "=== Safe Traversal Verification ==="
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# Build utilities if not already built
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if [ ! -f "$PROJECT_ROOT/target/release/rm" ]; then
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echo "Building utilities..."
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cd "$PROJECT_ROOT"
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cargo build --release --quiet
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fi
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# Check if we should use individual binaries or multicall binary
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# Prefer individual binaries for more accurate testing
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if [ -f "$PROJECT_ROOT/target/release/rm" ]; then
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echo "Using individual binaries (preferred for testing)"
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USE_MULTICALL=0
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elif [ -f "$PROJECT_ROOT/target/release/coreutils" ]; then
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echo "Using multicall binary: $PROJECT_ROOT/target/release/coreutils"
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USE_MULTICALL=1
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COREUTILS_BIN="$PROJECT_ROOT/target/release/coreutils"
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else
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echo "No binaries found - please build first"
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exit 1
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fi
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cd "$TEMP_DIR"
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# Create test directory structure
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mkdir -p test_dir/sub1/sub2/sub3
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echo "test1" > test_dir/file1.txt
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echo "test2" > test_dir/sub1/file2.txt
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echo "test3" > test_dir/sub1/sub2/file3.txt
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echo "test4" > test_dir/sub1/sub2/sub3/file4.txt
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check_utility() {
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local util="$1"
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local trace_syscalls="$2"
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local expected_syscalls="$3"
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local test_args="$4"
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local test_name="$5"
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echo ""
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echo "Testing $util ($test_name)..."
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local strace_log="strace_${util}_${test_name}.log"
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# Choose binary to use
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if [ "$USE_MULTICALL" -eq 1 ]; then
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local util_cmd="$COREUTILS_BIN $util"
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else
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local util_path="$PROJECT_ROOT/target/release/$util"
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if [ ! -f "$util_path" ]; then
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fail_immediately "$util binary not found at $util_path"
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fi
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local util_cmd="$util_path"
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fi
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# Run utility under strace
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strace -f -e trace="$trace_syscalls" -o "$strace_log" \
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$util_cmd $test_args 2>/dev/null || true
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cat $strace_log
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# Check for expected safe syscalls
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local found_safe=0
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for syscall in $expected_syscalls; do
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if grep -q "$syscall" "$strace_log"; then
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echo "✓ Found $syscall() (safe traversal)"
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found_safe=$((found_safe + 1))
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else
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fail_immediately "Missing $syscall() (safe traversal not active for $util)"
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fi
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done
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# Count detailed syscall statistics
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local openat_count unlinkat_count fchmodat_count fchownat_count newfstatat_count renameat_count
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local unlink_count rmdir_count chmod_count chown_count safe_ops unsafe_ops
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openat_count=$(grep -c "openat(" "$strace_log" 2>/dev/null | tr -d '\n' || echo "0")
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unlinkat_count=$(grep -c "unlinkat(" "$strace_log" 2>/dev/null | tr -d '\n' || echo "0")
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fchmodat_count=$(grep -c "fchmodat(" "$strace_log" 2>/dev/null | tr -d '\n' || echo "0")
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fchownat_count=$(grep -c "fchownat(" "$strace_log" 2>/dev/null | tr -d '\n' || echo "0")
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newfstatat_count=$(grep -c "newfstatat(" "$strace_log" 2>/dev/null | tr -d '\n' || echo "0")
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renameat_count=$(grep -c "renameat(" "$strace_log" 2>/dev/null | tr -d '\n' || echo "0")
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# Count old unsafe syscalls (exclude the trace line prefix)
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unlink_count=$(grep -cE "\bunlink\(" "$strace_log" 2>/dev/null | tr -d '\n' || echo "0")
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rmdir_count=$(grep -cE "\brmdir\(" "$strace_log" 2>/dev/null | tr -d '\n' || echo "0")
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chmod_count=$(grep -cE "\bchmod\(" "$strace_log" 2>/dev/null | tr -d '\n' || echo "0")
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chown_count=$(grep -cE "\b(chown|lchown)\(" "$strace_log" 2>/dev/null | tr -d '\n' || echo "0")
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# Ensure all variables are integers
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[ -z "$openat_count" ] && openat_count=0
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[ -z "$unlinkat_count" ] && unlinkat_count=0
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[ -z "$fchmodat_count" ] && fchmodat_count=0
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[ -z "$fchownat_count" ] && fchownat_count=0
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[ -z "$newfstatat_count" ] && newfstatat_count=0
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[ -z "$renameat_count" ] && renameat_count=0
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[ -z "$unlink_count" ] && unlink_count=0
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[ -z "$rmdir_count" ] && rmdir_count=0
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[ -z "$chmod_count" ] && chmod_count=0
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[ -z "$chown_count" ] && chown_count=0
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# Calculate totals
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safe_ops=$((openat_count + unlinkat_count + fchmodat_count + fchownat_count + newfstatat_count + renameat_count))
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unsafe_ops=$((unlink_count + rmdir_count + chmod_count + chown_count))
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echo " Strace statistics:"
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echo " Safe syscalls: openat=$openat_count unlinkat=$unlinkat_count fchmodat=$fchmodat_count fchownat=$fchownat_count newfstatat=$newfstatat_count renameat=$renameat_count"
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echo " Unsafe syscalls: unlink=$unlink_count rmdir=$rmdir_count chmod=$chmod_count chown/lchown=$chown_count"
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echo " Total: safe=$safe_ops unsafe=$unsafe_ops"
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# For rm specifically, we expect unlinkat instead of unlink/rmdir for file operations
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# Note: A single rmdir() for the root directory is acceptable because:
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# 1. The root directory path is provided by the user (not discovered during traversal)
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# 2. There's no TOCTOU race - we're not resolving paths during recursive operations
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# 3. After safe traversal removes all contents via unlinkat(), rmdir() is safe for the empty root
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if [ "$util" = "rm" ]; then
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if [ "$unlinkat_count" -gt 0 ] && [ "$unlink_count" -eq 0 ] && [ "$rmdir_count" -le 1 ]; then
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echo "✓ Using safe syscalls (unlinkat for traversal)"
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if [ "$rmdir_count" -eq 1 ]; then
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echo " Note: Single rmdir() for root directory is acceptable"
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fi
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elif [ "$unlink_count" -gt 0 ] || [ "$rmdir_count" -gt 1 ]; then
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fail_immediately "$util is UNSAFE: Using unlink/rmdir for file operations (unlink=$unlink_count rmdir=$rmdir_count unlinkat=$unlinkat_count) - vulnerable to TOCTOU attacks"
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else
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echo "⚠ No file removal operations detected"
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fi
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elif [ "$safe_ops" -gt 0 ] && [ "$unsafe_ops" -eq 0 ]; then
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echo "✓ Using only safe syscalls"
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elif [ "$safe_ops" -gt 0 ] && [ "$safe_ops" -ge "$unsafe_ops" ]; then
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echo "✓ Using primarily safe syscalls"
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elif [ "$found_safe" -gt 0 ]; then
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echo "⚠ Some safe syscalls found but mixed with unsafe ops"
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else
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fail_immediately "$util is not using safe traversal"
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fi
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}
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# Get list of available utilities
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if [ "$USE_MULTICALL" -eq 1 ]; then
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AVAILABLE_UTILS=$($COREUTILS_BIN --list)
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else
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AVAILABLE_UTILS=""
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for util in rm chmod chown chgrp du mv; do
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if [ -f "$PROJECT_ROOT/target/release/$util" ]; then
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AVAILABLE_UTILS="$AVAILABLE_UTILS $util"
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fi
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done
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fi
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# Test rm - should use openat, unlinkat, newfstatat
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if echo "$AVAILABLE_UTILS" | grep -q "rm"; then
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cp -r test_dir test_rm
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check_utility "rm" "openat,unlinkat,newfstatat,unlink,rmdir" "openat" "-rf test_rm" "recursive_remove"
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fi
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# Test chmod - should use openat, fchmodat, newfstatat
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if echo "$AVAILABLE_UTILS" | grep -q "chmod"; then
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cp -r test_dir test_chmod
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check_utility "chmod" "openat,fchmodat,newfstatat,chmod" "openat fchmodat" "-R 755 test_chmod" "recursive_chmod"
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fi
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# Test chown - should use openat, fchownat, newfstatat
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if echo "$AVAILABLE_UTILS" | grep -q "chown"; then
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cp -r test_dir test_chown
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USER_ID=$(id -u)
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GROUP_ID=$(id -g)
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check_utility "chown" "openat,fchownat,newfstatat,chown,lchown" "openat fchownat" "-R $USER_ID:$GROUP_ID test_chown" "recursive_chown"
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fi
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# Test chgrp - should use openat, fchownat, newfstatat
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if echo "$AVAILABLE_UTILS" | grep -q "chgrp"; then
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cp -r test_dir test_chgrp
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check_utility "chgrp" "openat,fchownat,newfstatat,chown,lchown" "openat fchownat" "-R $GROUP_ID test_chgrp" "recursive_chgrp"
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fi
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# Test du - should use openat, newfstatat
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if echo "$AVAILABLE_UTILS" | grep -q "du"; then
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cp -r test_dir test_du
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check_utility "du" "openat,newfstatat,stat,lstat" "openat" "-a test_du" "directory_usage"
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fi
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# Test mv - should use openat, renameat for directory moves
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if echo "$AVAILABLE_UTILS" | grep -q "mv"; then
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mkdir -p test_mv_src/sub
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echo "test" > test_mv_src/file.txt
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echo "test" > test_mv_src/sub/file2.txt
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check_utility "mv" "openat,renameat,newfstatat,rename" "openat" "test_mv_src test_mv_dst" "move_directory"
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fi
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echo ""
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echo "=== Additional Safety Checks ==="
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# Check for dangerous patterns across all logs
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echo "Checking for dangerous path resolution patterns..."
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echo "✓ Basic safe traversal verification completed"
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# Check that we're not doing excessive path resolutions (sign of TOCTOU vulnerability)
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echo "Checking path resolution frequency..."
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for log in strace_*.log; do
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if [ -f "$log" ]; then
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path_resolutions=$(grep -c "test_" "$log" 2>/dev/null || echo "0")
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if [ "$path_resolutions" -gt 20 ]; then
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echo "⚠ $log: High path resolution count ($path_resolutions) - potential TOCTOU risk"
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fi
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fi
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done
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echo ""
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echo "=== Summary ==="
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echo "All utilities are using safe traversal correctly!"

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