fix: preserve quoted args when deferring to tagged install script (#5363)

The installer word-split the original arguments when piping into a tagged release's `install.sh`, so `-b '/tmp/syft install path'` arrived as three words and the trailing word was treated as a release tag.

- argument parsing moved into `parse_install_args` so `main` keeps its original args
- tagged script is invoked with `"$@"` instead of the unquoted `PROGRAM_ARGS`

Port of anchore/grype#3738

Signed-off-by: Alex Goodman <wagoodman@users.noreply.github.com>

install.sh

@@ -8,7 +8,6 @@ REPO="${PROJECT_NAME}"
 GITHUB_DOWNLOAD_PREFIX=https://github.com/${OWNER}/${REPO}/releases/download
 INSTALL_SH_BASE_URL=https://get.anchore.io/${PROJECT_NAME}
 LEGACY_INSTALL_SH_BASE_URL=https://raw.githubusercontent.com/${OWNER}/${PROJECT_NAME}
-PROGRAM_ARGS=$@
 
 # signature verification options
 
@@ -791,7 +790,7 @@ prep_signature_verification() {
   fi
 }
 
-main() (
+parse_install_args() {
   # parse arguments
 
   # note: never change default install directory (this must always be backwards compatible)
@@ -831,6 +830,11 @@ EOF
 
   set +u
   tag=$1
+  set -u
+}
+
+main() (
+  parse_install_args "$@"
 
   if [ -z "${tag}" ]; then
     log_info "checking github for the current release tag"
@@ -838,7 +842,6 @@ EOF
   else
     log_info "checking github for release tag='${tag}'"
   fi
-  set -u
 
   if ! tag=$(get_release_tag "${OWNER}" "${REPO}" "${tag}"); then
       log_err "unable to find tag='${tag}'"
@@ -869,7 +872,7 @@ EOF
           log_warn "failed to fetch from ${INSTALL_SH_BASE_URL}, trying fallback URL"
           install_script=$(http_copy "${LEGACY_INSTALL_SH_BASE_URL}/${tag}/install.sh" "")
       fi
-      echo "${install_script}" | sh -s -- ${PROGRAM_ARGS}
+      echo "${install_script}" | sh -s -- "$@"
       exit $?
   fi
 

test/install/5_release_script_args_test.sh

@@ -0,0 +1,41 @@
+. test_harness.sh
+
+# make certain main defers to the (stubbed) tagged release script regardless of the caller's env
+DOWNLOAD_TAG_INSTALL_SCRIPT=true
+
+get_release_tag() {
+  printf '%s\n' "$3"
+}
+
+prep_signature_verification() {
+  return 0
+}
+
+# the "tagged release script" records each argument it receives, one bracketed arg per line
+http_copy() {
+  cat <<'SCRIPT'
+printf '[%s]\n' "$@" > "$INSTALL_ARG_CAPTURE"
+SCRIPT
+}
+
+test_release_script_receives_original_args() {
+  test_dir=$(mktemp -d)
+  INSTALL_ARG_CAPTURE="${test_dir}/actual"
+  export INSTALL_ARG_CAPTURE
+
+  # note: paths are read here instead of passed to run_test_case, which word-splits its arguments
+  while IFS= read -r install_path; do
+    main -b "${install_path}" -d v0.80.0
+
+    printf '[%s]\n' -b "${install_path}" -d v0.80.0 > "${test_dir}/expected"
+    assertFilesEqual "${test_dir}/expected" "${INSTALL_ARG_CAPTURE}" "args forwarded to the release script should match the original args (path='${install_path}')"
+  done <<'PATHS'
+/tmp/bin with spaces
+/tmp/bin*
+/tmp/it's "quoted"
+PATHS
+
+  rm -rf -- "${test_dir}"
+}
+
+run_test_case test_release_script_receives_original_args