Bound the last pointer-destination string copies in htsserver.c

Clears htsserver.c's five remaining unbounded strcpybuff/strcatbuff/
strncatbuff pointer-destination sites, the last in the tree, completing the
htssafe pointer-destination migration.

Four are behavior-preserving: each destination's capacity is known at the
call site, so the explicit-size form bounds by the same allocation the raw
copy already relied on (smallserver's POST buffer over buffer_size, the
template name_[1026] scratch over its own size with n already < 1024, the
exact-fit malloc(len+1) lang-key copy).

htslang_load's two writes into its caller buffer were raw strcpy of a
language-name string read from the lang files; a name longer than the
caller's lang_str[1024] would have overflowed. Thread a limit_size through
the (static, internal) signature and bound both writes; the NULL-limit
callers pass 0.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
Signed-off-by: Xavier Roche <roche@httrack.com>

.github/workflows/ci.yml

@@ -320,20 +320,37 @@ jobs:
   lint:
     name: lint (shellcheck, shfmt)
     runs-on: ubuntu-24.04
+    env:
+      SHFMT_VERSION: v3.8.0
     steps:
       - uses: actions/checkout@v6
 
+      # shfmt is a pinned release binary, so it never changes: cache it keyed on
+      # the version. Same rationale as the git-clang-format driver below -- avoid
+      # re-downloading an unchanging file from github.com on every run.
+      - name: Cache shfmt binary
+        uses: actions/cache@v4
+        with:
+          path: ~/.cache/shfmt/shfmt
+          key: shfmt-${{ env.SHFMT_VERSION }}-${{ runner.arch }}
+
       - name: Install linters
-        env:
-          SHFMT_VERSION: v3.8.0
         run: |
           set -euo pipefail
           sudo apt-get update
           sudo apt-get install -y --no-install-recommends shellcheck
-          # shfmt is not packaged in apt; fetch a pinned release binary.
-          curl -fsSL -o /tmp/shfmt \
-            "https://github.com/mvdan/sh/releases/download/${SHFMT_VERSION}/shfmt_${SHFMT_VERSION}_linux_$(dpkg --print-architecture)"
-          sudo install -m 0755 /tmp/shfmt /usr/local/bin/shfmt
+          # shfmt is not packaged in apt; fetch a pinned release binary (cold
+          # cache only), retrying through transient errors.
+          shfmt="$HOME/.cache/shfmt/shfmt"
+          if [ ! -s "$shfmt" ]; then
+            echo "shfmt cache MISS: fetching ${SHFMT_VERSION} from github.com"
+            mkdir -p "$(dirname "$shfmt")"
+            curl --retry 5 --retry-all-errors -fsSL -o "$shfmt" \
+              "https://github.com/mvdan/sh/releases/download/${SHFMT_VERSION}/shfmt_${SHFMT_VERSION}_linux_$(dpkg --print-architecture)"
+          else
+            echo "shfmt cache HIT: using cached ${SHFMT_VERSION}"
+          fi
+          sudo install -m 0755 "$shfmt" /usr/local/bin/shfmt
 
       # Lint the scripts we maintain; the legacy scripts are a separate cleanup.
       - name: shellcheck
@@ -349,11 +366,24 @@ jobs:
     name: format (clang-format-19, changed lines)
     if: github.event_name == 'pull_request'
     runs-on: ubuntu-24.04
+    env:
+      # Single-source the tag so the cache key and the fetch URL can never drift.
+      LLVM_TAG: llvmorg-19.1.7
     steps:
       - uses: actions/checkout@v6
         with:
           fetch-depth: 0
 
+      # The git-clang-format driver is pinned to an immutable release tag, so the
+      # fetched file never changes: cache it keyed on the tag. raw.githubusercontent.com
+      # 429-rate-limits the shared runner egress IPs, and re-downloading an unchanging
+      # file every run was the only thing that could (and did) hit that limit.
+      - name: Cache git-clang-format driver
+        uses: actions/cache@v4
+        with:
+          path: ~/.cache/git-clang-format/git-clang-format
+          key: git-clang-format-${{ env.LLVM_TAG }}
+
       - name: Install clang-format 19 (pinned, from apt.llvm.org)
         run: |
           set -euo pipefail
@@ -364,11 +394,17 @@ jobs:
             | sudo tee /etc/apt/sources.list.d/llvm-19.list >/dev/null
           sudo apt-get update
           sudo apt-get install -y --no-install-recommends clang-format-19
-          # git-clang-format driver, pinned to an immutable release tag (not a
-          # moving branch) since we curl and then execute it.
-          sudo curl -fsSL -o /usr/local/bin/git-clang-format \
-            https://raw.githubusercontent.com/llvm/llvm-project/llvmorg-19.1.7/clang/tools/clang-format/git-clang-format
-          sudo chmod 0755 /usr/local/bin/git-clang-format
+          # Cold cache only: fetch the driver, retrying through transient 429s.
+          driver="$HOME/.cache/git-clang-format/git-clang-format"
+          if [ ! -s "$driver" ]; then
+            echo "git-clang-format cache MISS: fetching ${LLVM_TAG} from raw.githubusercontent.com"
+            mkdir -p "$(dirname "$driver")"
+            curl --retry 5 --retry-all-errors -fsSL -o "$driver" \
+              "https://raw.githubusercontent.com/llvm/llvm-project/${LLVM_TAG}/clang/tools/clang-format/git-clang-format"
+          else
+            echo "git-clang-format cache HIT: using cached ${LLVM_TAG}"
+          fi
+          sudo install -m 0755 "$driver" /usr/local/bin/git-clang-format
           clang-format-19 --version
 
       - name: Check formatting of changed lines

src/htsserver.c

@@ -129,7 +129,8 @@ HTS_UNUSED static int linputsoc_t(T_SOC soc, char *s, int max, int timeout);
 HTS_UNUSED static int linput(FILE * fp, char *s, int max);
 
 /* Language files */
-HTS_UNUSED static int htslang_load(char *limit_to, const char *apppath);
+HTS_UNUSED static int htslang_load(char *limit_to, size_t limit_size,
+                                   const char *apppath);
 HTS_UNUSED static void conv_printf(const char *from, char *to);
 HTS_UNUSED static void LANG_DELETE(void);
 HTS_UNUSED static void LANG_INIT(const char *path);
@@ -325,7 +326,7 @@ int smallserver(T_SOC soc, char *url, char *method, char *data, char *path) {
 
   /* Load strings */
   htslang_init();
-  if (!htslang_load(NULL, path)) {
+  if (!htslang_load(NULL, 0, path)) {
     fprintf(stderr, "unable to find lang.def and/or lang/ strings in %s\n",
             path);
     return 0;
@@ -511,7 +512,7 @@ int smallserver(T_SOC soc, char *url, char *method, char *data, char *path) {
         char *s = buffer;
         char *e, *f;
 
-        strcatbuff(buffer, "&");
+        strlcatbuff(buffer, "&", buffer_size);
         while(s && (e = strchr(s, '=')) && (f = strchr(s, '&'))) {
           const char *ua;
           String sua = STRING_EMPTY;
@@ -935,7 +936,7 @@ int smallserver(T_SOC soc, char *url, char *method, char *data, char *path) {
                     int listDefault = 0;
 
                     name[0] = '\0';
-                    strncatbuff(name, str, n);
+                    strlncatbuff(name, str, sizeof(name_), n);
 
                     if (strncmp(name, "/*", 2) == 0) {
                       /* comments */
@@ -1490,7 +1491,7 @@ int smallserver_setkeyarr(const char *key, int id, const char *key2, const char
   return coucal_write(NewLangList, tmp, (intptr_t) strdup(value));
 }
 
-static int htslang_load(char *limit_to, const char *path) {
+static int htslang_load(char *limit_to, size_t limit_size, const char *path) {
   const char *hashname;
   char catbuff[CATBUFF_SIZE];
 
@@ -1545,7 +1546,7 @@ static int htslang_load(char *limit_to, const char *path) {
             char *const buff = (char *) malloc(len + 1);
 
             if (buff) {
-              strcpybuff(buff, intkey);
+              strlcpybuff(buff, intkey, len + 1);
               coucal_add(NewLangStrKeys, key, (intptr_t) buff);
             }
           }
@@ -1568,9 +1569,9 @@ static int htslang_load(char *limit_to, const char *path) {
   /* Get only language name */
   if (limit_to) {
     if (hashname)
-      strcpybuff(limit_to, hashname);
+      strlcpybuff(limit_to, hashname, limit_size);
     else
-      strcpybuff(limit_to, "???");
+      strlcpybuff(limit_to, "???", limit_size);
     return 0;
   }
 
@@ -1750,7 +1751,7 @@ static void LANG_INIT(const char *path) {
 static int LANG_T(const char *path, int l) {
   if (l >= 0) {
     QLANG_T(l);
-    htslang_load(NULL, path);
+    htslang_load(NULL, 0, path);
   }
   return QLANG_T(-1);           // 0=default (english)
 }
@@ -1764,7 +1765,7 @@ static int LANG_SEARCH(const char *path, const char *iso) {
   do {
     QLANG_T(i);
     strcpybuff(lang_str, "LANGUAGE_ISO");
-    htslang_load(lang_str, path);
+    htslang_load(lang_str, sizeof(lang_str), path);
     if (strfield(iso, lang_str)) {
       found = i;
     }
@@ -1783,10 +1784,10 @@ static int LANG_LIST(const char *path, char *buffer, size_t buffer_size) {
   do {
     QLANG_T(i);
     strlcpybuff(lang_str, "LANGUAGE_NAME", buffer_size);
-    htslang_load(lang_str, path);
+    htslang_load(lang_str, sizeof(lang_str), path);
     if (strlen(lang_str) > 0) {
       if (buffer[0])
-        strcatbuff(buffer, "\n");
+        strlcatbuff(buffer, "\n", buffer_size);
       strlcatbuff(buffer, lang_str, buffer_size);
     }
     i++;