diff options
Diffstat (limited to 'scripts/check-uapi.sh')
| -rwxr-xr-x | scripts/check-uapi.sh | 573 |
1 files changed, 573 insertions, 0 deletions
diff --git a/scripts/check-uapi.sh b/scripts/check-uapi.sh new file mode 100755 index 000000000000..955581735cb3 --- /dev/null +++ b/scripts/check-uapi.sh @@ -0,0 +1,573 @@ +#!/bin/bash +# SPDX-License-Identifier: GPL-2.0-only +# Script to check commits for UAPI backwards compatibility + +set -o errexit +set -o pipefail + +print_usage() { + name=$(basename "$0") + cat << EOF +$name - check for UAPI header stability across Git commits + +By default, the script will check to make sure the latest commit (or current +dirty changes) did not introduce ABI changes when compared to HEAD^1. You can +check against additional commit ranges with the -b and -p options. + +The script will not check UAPI headers for architectures other than the one +defined in ARCH. + +Usage: $name [-b BASE_REF] [-p PAST_REF] [-j N] [-l ERROR_LOG] [-i] [-q] [-v] + +Options: + -b BASE_REF Base git reference to use for comparison. If unspecified or empty, + will use any dirty changes in tree to UAPI files. If there are no + dirty changes, HEAD will be used. + -p PAST_REF Compare BASE_REF to PAST_REF (e.g. -p v6.1). If unspecified or empty, + will use BASE_REF^1. Must be an ancestor of BASE_REF. Only headers + that exist on PAST_REF will be checked for compatibility. + -j JOBS Number of checks to run in parallel (default: number of CPU cores). + -l ERROR_LOG Write error log to file (default: no error log is generated). + -i Ignore ambiguous changes that may or may not break UAPI compatibility. + -q Quiet operation. + -v Verbose operation (print more information about each header being checked). + +Environmental args: + ABIDIFF Custom path to abidiff binary + CC C compiler (default is "gcc") + ARCH Target architecture for the UAPI check (default is host arch) + +Exit codes: + $SUCCESS) Success + $FAIL_ABI) ABI difference detected + $FAIL_PREREQ) Prerequisite not met +EOF +} + +readonly SUCCESS=0 +readonly FAIL_ABI=1 +readonly FAIL_PREREQ=2 + +# Print to stderr +eprintf() { + # shellcheck disable=SC2059 + printf "$@" >&2 +} + +# Expand an array with a specific character (similar to Python string.join()) +join() { + local IFS="$1" + shift + printf "%s" "$*" +} + +# Create abidiff suppressions +gen_suppressions() { + # Common enum variant names which we don't want to worry about + # being shifted when new variants are added. + local -a enum_regex=( + ".*_AFTER_LAST$" + ".*_CNT$" + ".*_COUNT$" + ".*_END$" + ".*_LAST$" + ".*_MASK$" + ".*_MAX$" + ".*_MAX_BIT$" + ".*_MAX_BPF_ATTACH_TYPE$" + ".*_MAX_ID$" + ".*_MAX_SHIFT$" + ".*_NBITS$" + ".*_NETDEV_NUMHOOKS$" + ".*_NFT_META_IIFTYPE$" + ".*_NL80211_ATTR$" + ".*_NLDEV_NUM_OPS$" + ".*_NUM$" + ".*_NUM_ELEMS$" + ".*_NUM_IRQS$" + ".*_SIZE$" + ".*_TLSMAX$" + "^MAX_.*" + "^NUM_.*" + ) + + # Common padding field names which can be expanded into + # without worrying about users. + local -a padding_regex=( + ".*end$" + ".*pad$" + ".*pad[0-9]?$" + ".*pad_[0-9]?$" + ".*padding$" + ".*padding[0-9]?$" + ".*padding_[0-9]?$" + ".*res$" + ".*resv$" + ".*resv[0-9]?$" + ".*resv_[0-9]?$" + ".*reserved$" + ".*reserved[0-9]?$" + ".*reserved_[0-9]?$" + ".*rsvd[0-9]?$" + ".*unused$" + ) + + cat << EOF +[suppress_type] + type_kind = enum + changed_enumerators_regexp = $(join , "${enum_regex[@]}") +EOF + + for p in "${padding_regex[@]}"; do + cat << EOF +[suppress_type] + type_kind = struct + has_data_member_inserted_at = offset_of_first_data_member_regexp(${p}) +EOF + done + +if [ "$IGNORE_AMBIGUOUS_CHANGES" = "true" ]; then + cat << EOF +[suppress_type] + type_kind = struct + has_data_member_inserted_at = end + has_size_change = yes +EOF +fi +} + +# Check if git tree is dirty +tree_is_dirty() { + ! git diff --quiet +} + +# Get list of files installed in $ref +get_file_list() { + local -r ref="$1" + local -r tree="$(get_header_tree "$ref")" + + # Print all installed headers, filtering out ones that can't be compiled + find "$tree" -type f -name '*.h' -printf '%P\n' | grep -v -f "$INCOMPAT_LIST" +} + +# Add to the list of incompatible headers +add_to_incompat_list() { + local -r ref="$1" + + # Start with the usr/include/Makefile to get a list of the headers + # that don't compile using this method. + if [ ! -f usr/include/Makefile ]; then + eprintf "error - no usr/include/Makefile present at %s\n" "$ref" + eprintf "Note: usr/include/Makefile was added in the v5.3 kernel release\n" + exit "$FAIL_PREREQ" + fi + { + # shellcheck disable=SC2016 + printf 'all: ; @echo $(no-header-test)\n' + cat usr/include/Makefile + } | SRCARCH="$ARCH" make --always-make -f - | tr " " "\n" \ + | grep -v "asm-generic" >> "$INCOMPAT_LIST" + + # The makefile also skips all asm-generic files, but prints "asm-generic/%" + # which won't work for our grep match. Instead, print something grep will match. + printf "asm-generic/.*\.h\n" >> "$INCOMPAT_LIST" +} + +# Compile the simple test app +do_compile() { + local -r inc_dir="$1" + local -r header="$2" + local -r out="$3" + printf "int main(void) { return 0; }\n" | \ + "$CC" -c \ + -o "$out" \ + -x c \ + -O0 \ + -std=c90 \ + -fno-eliminate-unused-debug-types \ + -g \ + "-I${inc_dir}" \ + -include "$header" \ + - +} + +# Run make headers_install +run_make_headers_install() { + local -r ref="$1" + local -r install_dir="$(get_header_tree "$ref")" + make -j "$MAX_THREADS" ARCH="$ARCH" INSTALL_HDR_PATH="$install_dir" \ + headers_install > /dev/null +} + +# Install headers for both git refs +install_headers() { + local -r base_ref="$1" + local -r past_ref="$2" + + for ref in "$base_ref" "$past_ref"; do + printf "Installing user-facing UAPI headers from %s... " "${ref:-dirty tree}" + if [ -n "$ref" ]; then + git archive --format=tar --prefix="${ref}-archive/" "$ref" \ + | (cd "$TMP_DIR" && tar xf -) + ( + cd "${TMP_DIR}/${ref}-archive" + run_make_headers_install "$ref" + add_to_incompat_list "$ref" "$INCOMPAT_LIST" + ) + else + run_make_headers_install "$ref" + add_to_incompat_list "$ref" "$INCOMPAT_LIST" + fi + printf "OK\n" + done + sort -u -o "$INCOMPAT_LIST" "$INCOMPAT_LIST" + sed -i -e '/^$/d' "$INCOMPAT_LIST" +} + +# Print the path to the headers_install tree for a given ref +get_header_tree() { + local -r ref="$1" + printf "%s" "${TMP_DIR}/${ref}/usr" +} + +# Check file list for UAPI compatibility +check_uapi_files() { + local -r base_ref="$1" + local -r past_ref="$2" + local -r abi_error_log="$3" + + local passed=0; + local failed=0; + local -a threads=() + set -o errexit + + printf "Checking changes to UAPI headers between %s and %s...\n" "$past_ref" "${base_ref:-dirty tree}" + # Loop over all UAPI headers that were installed by $past_ref (if they only exist on $base_ref, + # there's no way they're broken and no way to compare anyway) + while read -r file; do + if [ "${#threads[@]}" -ge "$MAX_THREADS" ]; then + if wait "${threads[0]}"; then + passed=$((passed + 1)) + else + failed=$((failed + 1)) + fi + threads=("${threads[@]:1}") + fi + + check_individual_file "$base_ref" "$past_ref" "$file" & + threads+=("$!") + done < <(get_file_list "$past_ref") + + for t in "${threads[@]}"; do + if wait "$t"; then + passed=$((passed + 1)) + else + failed=$((failed + 1)) + fi + done + + if [ -n "$abi_error_log" ]; then + printf 'Generated by "%s %s" from git ref %s\n\n' \ + "$0" "$*" "$(git rev-parse HEAD)" > "$abi_error_log" + fi + + while read -r error_file; do + { + cat "$error_file" + printf "\n\n" + } | tee -a "${abi_error_log:-/dev/null}" >&2 + done < <(find "$TMP_DIR" -type f -name '*.error' | sort) + + total="$((passed + failed))" + if [ "$failed" -gt 0 ]; then + eprintf "error - %d/%d UAPI headers compatible with %s appear _not_ to be backwards compatible\n" \ + "$failed" "$total" "$ARCH" + if [ -n "$abi_error_log" ]; then + eprintf "Failure summary saved to %s\n" "$abi_error_log" + fi + else + printf "All %d UAPI headers compatible with %s appear to be backwards compatible\n" \ + "$total" "$ARCH" + fi + + return "$failed" +} + +# Check an individual file for UAPI compatibility +check_individual_file() { + local -r base_ref="$1" + local -r past_ref="$2" + local -r file="$3" + + local -r base_header="$(get_header_tree "$base_ref")/${file}" + local -r past_header="$(get_header_tree "$past_ref")/${file}" + + if [ ! -f "$base_header" ]; then + mkdir -p "$(dirname "$base_header")" + printf "==== UAPI header %s was removed between %s and %s ====" \ + "$file" "$past_ref" "$base_ref" \ + > "${base_header}.error" + return 1 + fi + + compare_abi "$file" "$base_header" "$past_header" "$base_ref" "$past_ref" +} + +# Perform the A/B compilation and compare output ABI +compare_abi() { + local -r file="$1" + local -r base_header="$2" + local -r past_header="$3" + local -r base_ref="$4" + local -r past_ref="$5" + local -r log="${TMP_DIR}/log/${file}.log" + local -r error_log="${TMP_DIR}/log/${file}.error" + + mkdir -p "$(dirname "$log")" + + if ! do_compile "$(get_header_tree "$base_ref")/include" "$base_header" "${base_header}.bin" 2> "$log"; then + { + warn_str=$(printf "==== Could not compile version of UAPI header %s at %s ====\n" \ + "$file" "$base_ref") + printf "%s\n" "$warn_str" + cat "$log" + printf -- "=%.0s" $(seq 0 ${#warn_str}) + } > "$error_log" + return 1 + fi + + if ! do_compile "$(get_header_tree "$past_ref")/include" "$past_header" "${past_header}.bin" 2> "$log"; then + { + warn_str=$(printf "==== Could not compile version of UAPI header %s at %s ====\n" \ + "$file" "$past_ref") + printf "%s\n" "$warn_str" + cat "$log" + printf -- "=%.0s" $(seq 0 ${#warn_str}) + } > "$error_log" + return 1 + fi + + local ret=0 + "$ABIDIFF" --non-reachable-types \ + --suppressions "$SUPPRESSIONS" \ + "${past_header}.bin" "${base_header}.bin" > "$log" || ret="$?" + if [ "$ret" -eq 0 ]; then + if [ "$VERBOSE" = "true" ]; then + printf "No ABI differences detected in %s from %s -> %s\n" \ + "$file" "$past_ref" "$base_ref" + fi + else + # Bits in abidiff's return code can be used to determine the type of error + if [ $((ret & 0x2)) -gt 0 ]; then + eprintf "error - abidiff did not run properly\n" + exit 1 + fi + + if [ "$IGNORE_AMBIGUOUS_CHANGES" = "true" ] && [ "$ret" -eq 4 ]; then + return 0 + fi + + # If the only changes were additions (not modifications to existing APIs), then + # there's no problem. Ignore these diffs. + if grep "Unreachable types summary" "$log" | grep -q "0 removed" && + grep "Unreachable types summary" "$log" | grep -q "0 changed"; then + return 0 + fi + + { + warn_str=$(printf "==== ABI differences detected in %s from %s -> %s ====" \ + "$file" "$past_ref" "$base_ref") + printf "%s\n" "$warn_str" + sed -e '/summary:/d' -e '/changed type/d' -e '/^$/d' -e 's/^/ /g' "$log" + printf -- "=%.0s" $(seq 0 ${#warn_str}) + if cmp "$past_header" "$base_header" > /dev/null 2>&1; then + printf "\n%s did not change between %s and %s...\n" "$file" "$past_ref" "${base_ref:-dirty tree}" + printf "It's possible a change to one of the headers it includes caused this error:\n" + grep '^#include' "$base_header" + printf "\n" + fi + } > "$error_log" + + return 1 + fi +} + +# Check that a minimum software version number is satisfied +min_version_is_satisfied() { + local -r min_version="$1" + local -r version_installed="$2" + + printf "%s\n%s\n" "$min_version" "$version_installed" \ + | sort -Vc > /dev/null 2>&1 +} + +# Make sure we have the tools we need and the arguments make sense +check_deps() { + ABIDIFF="${ABIDIFF:-abidiff}" + CC="${CC:-gcc}" + ARCH="${ARCH:-$(uname -m)}" + if [ "$ARCH" = "x86_64" ]; then + ARCH="x86" + fi + + local -r abidiff_min_version="2.4" + local -r libdw_min_version_if_clang="0.171" + + if ! command -v "$ABIDIFF" > /dev/null 2>&1; then + eprintf "error - abidiff not found!\n" + eprintf "Please install abigail-tools version %s or greater\n" "$abidiff_min_version" + eprintf "See: https://sourceware.org/libabigail/manual/libabigail-overview.html\n" + return 1 + fi + + local -r abidiff_version="$("$ABIDIFF" --version | cut -d ' ' -f 2)" + if ! min_version_is_satisfied "$abidiff_min_version" "$abidiff_version"; then + eprintf "error - abidiff version too old: %s\n" "$abidiff_version" + eprintf "Please install abigail-tools version %s or greater\n" "$abidiff_min_version" + eprintf "See: https://sourceware.org/libabigail/manual/libabigail-overview.html\n" + return 1 + fi + + if ! command -v "$CC" > /dev/null 2>&1; then + eprintf 'error - %s not found\n' "$CC" + return 1 + fi + + if "$CC" --version | grep -q clang; then + local -r libdw_version="$(ldconfig -v 2>/dev/null | grep -v SKIPPED | grep -m 1 -o 'libdw-[0-9]\+.[0-9]\+' | cut -c 7-)" + if ! min_version_is_satisfied "$libdw_min_version_if_clang" "$libdw_version"; then + eprintf "error - libdw version too old for use with clang: %s\n" "$libdw_version" + eprintf "Please install libdw from elfutils version %s or greater\n" "$libdw_min_version_if_clang" + eprintf "See: https://sourceware.org/elfutils/\n" + return 1 + fi + fi + + if [ ! -d "arch/${ARCH}" ]; then + eprintf 'error - ARCH "%s" is not a subdirectory under arch/\n' "$ARCH" + eprintf "Please set ARCH to one of:\n%s\n" "$(find arch -maxdepth 1 -mindepth 1 -type d -printf '%f ' | fmt)" + return 1 + fi + + if ! git rev-parse --is-inside-work-tree > /dev/null 2>&1; then + eprintf "error - this script requires the kernel tree to be initialized with Git\n" + return 1 + fi + + if ! git rev-parse --verify "$past_ref" > /dev/null 2>&1; then + printf 'error - invalid git reference "%s"\n' "$past_ref" + return 1 + fi + + if [ -n "$base_ref" ]; then + if ! git merge-base --is-ancestor "$past_ref" "$base_ref" > /dev/null 2>&1; then + printf 'error - "%s" is not an ancestor of base ref "%s"\n' "$past_ref" "$base_ref" + return 1 + fi + if [ "$(git rev-parse "$base_ref")" = "$(git rev-parse "$past_ref")" ]; then + printf 'error - "%s" and "%s" are the same reference\n' "$past_ref" "$base_ref" + return 1 + fi + fi +} + +run() { + local base_ref="$1" + local past_ref="$2" + local abi_error_log="$3" + shift 3 + + if [ -z "$KERNEL_SRC" ]; then + KERNEL_SRC="$(realpath "$(dirname "$0")"/..)" + fi + + cd "$KERNEL_SRC" + + if [ -z "$base_ref" ] && ! tree_is_dirty; then + base_ref=HEAD + fi + + if [ -z "$past_ref" ]; then + if [ -n "$base_ref" ]; then + past_ref="${base_ref}^1" + else + past_ref=HEAD + fi + fi + + if ! check_deps; then + exit "$FAIL_PREREQ" + fi + + TMP_DIR=$(mktemp -d) + readonly TMP_DIR + trap 'rm -rf "$TMP_DIR"' EXIT + + readonly INCOMPAT_LIST="${TMP_DIR}/incompat_list.txt" + touch "$INCOMPAT_LIST" + + readonly SUPPRESSIONS="${TMP_DIR}/suppressions.txt" + gen_suppressions > "$SUPPRESSIONS" + + # Run make install_headers for both refs + install_headers "$base_ref" "$past_ref" + + # Check for any differences in the installed header trees + if diff -r -q "$(get_header_tree "$base_ref")" "$(get_header_tree "$past_ref")" > /dev/null 2>&1; then + printf "No changes to UAPI headers were applied between %s and %s\n" "$past_ref" "${base_ref:-dirty tree}" + exit "$SUCCESS" + fi + + if ! check_uapi_files "$base_ref" "$past_ref" "$abi_error_log"; then + exit "$FAIL_ABI" + fi +} + +main() { + MAX_THREADS=$(nproc) + VERBOSE="false" + IGNORE_AMBIGUOUS_CHANGES="false" + quiet="false" + local base_ref="" + while getopts "hb:p:j:l:iqv" opt; do + case $opt in + h) + print_usage + exit "$SUCCESS" + ;; + b) + base_ref="$OPTARG" + ;; + p) + past_ref="$OPTARG" + ;; + j) + MAX_THREADS="$OPTARG" + ;; + l) + abi_error_log="$OPTARG" + ;; + i) + IGNORE_AMBIGUOUS_CHANGES="true" + ;; + q) + quiet="true" + VERBOSE="false" + ;; + v) + VERBOSE="true" + quiet="false" + ;; + *) + exit "$FAIL_PREREQ" + esac + done + + if [ "$quiet" = "true" ]; then + exec > /dev/null 2>&1 + fi + + run "$base_ref" "$past_ref" "$abi_error_log" "$@" +} + +main "$@" |