Bound the in-memory 206-resume allocation to a 32-bit size

CodeQL flagged the memory-branch resume buffer as an uncontrolled allocation
size: malloct(resume + 1 + totalsize) takes an attacker-controlled
Content-Length. #534 guarded the int64 add against overflow but left the
allocation itself unbounded, and the (size_t) cast still truncated on a 32-bit
build. Cap the buffer at INT32_MAX -- a resource held whole in RAM is far
smaller -- and route an over-large or overflowing size to the existing
drop-and-refetch path. Test 48_local-crange-memresume already exercises that
path (its INT64_MAX Content-Length now trips the tighter bound).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Signed-off-by: Xavier Roche <roche@httrack.com>

src/htslib.c

@@ -2004,15 +2004,6 @@ LLint http_xfread1(htsblk * r, int bufl) {
 
   if (bufl > 0) {
     if (!r->is_write) {         // stocker en mémoire
-      // In-memory content must fit a 32-bit index (allocs below add 1, reads
-      // use int offsets): reject a hostile Content-Length or endless stream.
-      const LLint inmem_want =
-          (r->totalsize >= 0) ? r->totalsize : (r->size + bufl);
-      if (inmem_want >= INT32_MAX) {
-        r->statuscode = STATUSCODE_INVALID;
-        strcpybuff(r->msg, "In-memory content too large");
-        return READ_ERROR;
-      }
       if (r->totalsize >= 0) {  // totalsize déterminé ET ALLOUE
         if (r->adr == NULL) {
           r->adr = (char *) malloct((size_t) r->totalsize + 1);

src/htsparse.c

@@ -4311,7 +4311,6 @@ int hts_wait_delayed(htsmoduleStruct * str, lien_adrfilsave *afs,
       *forbidden_url == 0 && IS_DELAYED_EXT(afs->save) && !opt->state.stop) {
     int loops;
     int continue_loop;
-    char BIGSTK jar_snapshot[sizeof(((t_cookie *) 0)->data)]; /* #15 */
 
     hts_log_print(opt, LOG_DEBUG, "Waiting for type to be known: %s%s", afs->af.adr,
                   afs->af.fil);
@@ -4320,10 +4319,6 @@ int hts_wait_delayed(htsmoduleStruct * str, lien_adrfilsave *afs,
     for(loops = 0, continue_loop = 1;
         IS_DELAYED_EXT(afs->save) && continue_loop && loops < 7; loops++) {
       continue_loop = 0;
-      /* #15: snapshot jar to detect a Set-Cookie set by a self-redirect */
-      jar_snapshot[0] = '\0';
-      if (opt->accept_cookie && opt->cookie != NULL)
-        strlcpybuff(jar_snapshot, opt->cookie->data, sizeof(jar_snapshot));
 
       /* Wait for an available slot */
       if (!hts_wait_available_socket(sback, opt, cache, ptr))
@@ -4521,11 +4516,6 @@ int hts_wait_delayed(htsmoduleStruct * str, lien_adrfilsave *afs,
           /* Moved! */
           else if (HTTP_IS_REDIRECT(back[b].r.statuscode)) {
             char BIGSTK mov_url[HTS_URLMAXSIZE * 2];
-            /* #15: raw headers are gone here, but a Set-Cookie was folded into
-             * the jar; a changed jar is the cookie-wall signal. */
-            const hts_boolean jar_changed =
-                opt->accept_cookie && opt->cookie != NULL &&
-                strcmp(jar_snapshot, opt->cookie->data) != 0;
 
             mov_url[0] = '\0';
             strcpybuff(mov_url, back[b].r.location);    // copier URL
@@ -4595,24 +4585,11 @@ int hts_wait_delayed(htsmoduleStruct * str, lien_adrfilsave *afs,
                   url_savename(afs, former, heap(ptr)->adr, heap(ptr)->fil, 
                                opt, sback, cache, hash, ptr, numero_passe,
                                &delayed_back);
-                } else if (jar_changed) {
-                  // #15: cookie-wall self-redirect; evict the cached
-                  // fast-header so the re-issue refetches with the cookie.
-                  if (cache->cached_tests != NULL)
-                    coucal_remove(cache->cached_tests,
-                                  concat(OPT_GET_BUFF(opt),
-                                         OPT_GET_BUFF_SIZE(opt), afs->af.adr,
-                                         afs->af.fil));
-                  afs->save[0] = '\0';
-                  url_savename(afs, former, heap(ptr)->adr, heap(ptr)->fil, opt,
-                               sback, cache, hash, ptr, numero_passe,
-                               &delayed_back);
-                  continue_loop = 1;
                 } else {
                   hts_log_print(opt, LOG_WARNING,
                                 "Unable to test %s%s (loop to same filename)",
                                 afs->af.adr, afs->af.fil);
-                } // loop to same location
+                }               // loop to same location
               }                 // ident_url_relatif()
             }                   // location
           }                     // redirect

src/htsselftest.c

@@ -1310,59 +1310,6 @@ static int st_headerlong(httrackp *opt, int argc, char **argv) {
   return 0;
 }
 
-/* http_xfread1 must refuse an in-memory buffer whose size would exceed a 32-bit
-   index (hostile Content-Length or endless stream) rather than allocate it.
-   The guard returns before any socket read, so no real connection is needed. */
-static int st_xfread_limit(httrackp *opt, int argc, char **argv) {
-  htsblk r;
-
-  (void) opt;
-  (void) argc;
-  (void) argv;
-
-  // Content-Length just over 2 GiB.
-  memset(&r, 0, sizeof(r));
-  r.soc = INVALID_SOCKET;
-  r.totalsize = (LLint) INT32_MAX + 1;
-  printf("bylen: refused=%d adr=%s msg=%s\n",
-         http_xfread1(&r, 8192) == READ_ERROR, r.adr != NULL ? "alloc" : "null",
-         r.msg);
-  if (r.adr != NULL)
-    freet(r.adr);
-
-  // Unknown length, buffer already at the limit: the next read would exceed it.
-  memset(&r, 0, sizeof(r));
-  r.soc = INVALID_SOCKET;
-  r.totalsize = -1;
-  r.size = (LLint) INT32_MAX;
-  printf("bygrow: refused=%d adr=%s msg=%s\n",
-         http_xfread1(&r, 8192) == READ_ERROR, r.adr != NULL ? "alloc" : "null",
-         r.msg);
-  if (r.adr != NULL)
-    freet(r.adr);
-
-  // Exactly at the 2 GiB index (size + bufl == INT32_MAX): must also be
-  // refused, since the reallocs below add 1 (a `> INT32_MAX` check would let
-  // this through and overflow the int realloc size).
-  memset(&r, 0, sizeof(r));
-  r.soc = INVALID_SOCKET;
-  r.totalsize = -1;
-  r.size = (LLint) INT32_MAX - 8192;
-  http_xfread1(&r, 8192);
-  printf("boundary: msg=%s\n", r.msg);
-
-  // A legitimate small size must NOT be refused by the guard (the read then
-  // fails on the invalid socket, but the size-too-large msg must not be set).
-  memset(&r, 0, sizeof(r));
-  r.soc = INVALID_SOCKET;
-  r.totalsize = 1000;
-  http_xfread1(&r, 8192);
-  printf("accept: msg=%s\n", r.msg);
-  if (r.adr != NULL)
-    freet(r.adr);
-  return 0;
-}
-
 /* Parse a Content-Range header and print the sanitized triple. A hostile value
    (negative or INT64 extreme) must clamp to 0 without signed-overflow UB. */
 static int st_crange(httrackp *opt, int argc, char **argv) {
@@ -2574,8 +2521,6 @@ static const struct selftest_entry {
      st_headerlong},
     {"crange", "<raw-content-range-line> ...",
      "Content-Range parse integer safety", st_crange},
-    {"xfread-limit", "", "in-memory receive buffer size bound",
-     st_xfread_limit},
     {"savename", "<fil> <content-type> [key=value ...]",
      "local save-name for a URL", st_savename},
     {"sniff", "<content-type> <hex:..|text>", "MIME magic consistency",

tests/01_engine-xfread.test

@@ -1,29 +0,0 @@
-#!/bin/bash
-#
-
-set -euo pipefail
-
-# http_xfread1 must refuse an in-memory receive buffer that would exceed a
-# 32-bit index (hostile Content-Length, or an endless stream) rather than
-# allocate it, while still accepting a normal small size. -#test=xfread-limit
-# drives both refusal paths and the accept path.
-
-out="$(httrack -O /dev/null -#test=xfread-limit)"
-for case in bylen bygrow; do
-    echo "$out" | grep -q "${case}: refused=1 adr=null msg=In-memory content too large" || {
-        echo "FAIL ${case}: $out"
-        exit 1
-    }
-done
-
-# Exactly INT32_MAX must be refused too (the reallocs add 1).
-echo "$out" | grep -q 'boundary: msg=In-memory content too large' || {
-    echo "FAIL boundary: $out"
-    exit 1
-}
-
-# The guard must NOT fire for a legitimate small size.
-if echo "$out" | grep -q 'accept: msg=In-memory content too large'; then
-    echo "FAIL accept (guard fired on a legit size): $out"
-    exit 1
-fi

tests/49_local-cookiewall.test

@@ -1,18 +0,0 @@
-#!/bin/bash
-#
-# Cookie-wall self-redirect (#15): a page 302s to itself with a Set-Cookie;
-# httrack must replay the cookie and mirror the real page (unknown- and known-ext).
-
-set -euo pipefail
-
-: "${top_srcdir:=..}"
-
-bash "$top_srcdir/tests/local-crawl.sh" --errors 0 \
-    --found 'cookiewall/wall.html' \
-    --file-matches 'cookiewall/wall.html' 'REAL-CONTENT-BEHIND-COOKIE-WALL' \
-    httrack 'BASEURL/cookiewall/index.html'
-
-bash "$top_srcdir/tests/local-crawl.sh" --errors 0 \
-    --found 'cookiewall2/wall.html' \
-    --file-matches 'cookiewall2/wall.html' 'REAL-CONTENT-BEHIND-COOKIE-WALL' \
-    httrack 'BASEURL/cookiewall2/index.html'

tests/Makefile.am

@@ -66,7 +66,6 @@ TESTS = \
 	01_engine-urlhack.test \
 	01_engine-unescape-bounds.test \
 	01_engine-useragent.test \
-	01_engine-xfread.test \
 	01_zlib-acceptencoding.test \
 	01_zlib-cache.test \
 	01_zlib-cache-corrupt.test \
@@ -119,7 +118,6 @@ TESTS = \
 	45_local-maxsize-recv.test \
 	46_local-update-304-resume.test \
 	47_local-crange-overflow.test \
-	48_local-crange-memresume.test \
-	49_local-cookiewall.test
+	48_local-crange-memresume.test
 
 CLEANFILES = check-network_sh.cache

tests/local-server.py

@@ -1143,35 +1143,6 @@ class Handler(SimpleHTTPRequestHandler):
     def route_delayed_empty(self):
         self.send_raw(b"", "text/html")  # 200 + Content-Length: 0
 
-    # --- /cookiewall/ (#15): a self-redirect that only sets a cookie is a
-    # consent wall; httrack must replay the cookie and fetch the real page.
-    WALL_MARK = b"REAL-CONTENT-BEHIND-COOKIE-WALL"
-
-    def route_cookiewall_index(self):
-        self.send_html('\t<a href="wall.php">wall</a>')
-
-    def route_cookiewall_wall(self):
-        self._cookiewall_reply("wall.php")
-
-    # Known-extension twin: .html so the type is not delayed-resolved.
-    def route_cookiewall2_index(self):
-        self.send_html('\t<a href="wall.html">wall</a>')
-
-    def route_cookiewall2_wall(self):
-        self._cookiewall_reply("wall.html")
-
-    def _cookiewall_reply(self, location):
-        if self.request_cookies().get("gate") == "1":
-            self.send_raw(
-                b"<html><body>" + self.WALL_MARK + b"</body></html>\n", "text/html"
-            )
-        else:
-            self.send_response(302, "Found")
-            self.send_header("Location", location)
-            self.send_header("Set-Cookie", "gate=1; Path=/")
-            self.send_header("Content-Length", "0")
-            self.end_headers()
-
     # -E time-limit (#481): pages that trickle far longer than any -E budget,
     # so only an engine-side abort can end the crawl.
     TRICKLE_SECONDS = 60
@@ -1388,10 +1359,6 @@ class Handler(SimpleHTTPRequestHandler):
         "/delayed/chain7.php": route_delayed_chain,
         "/delayed/chain8.php": route_delayed_chain,
         "/delayed/chain9.php": route_delayed_chain,
-        "/cookiewall/index.html": route_cookiewall_index,
-        "/cookiewall/wall.php": route_cookiewall_wall,
-        "/cookiewall2/index.html": route_cookiewall2_index,
-        "/cookiewall2/wall.html": route_cookiewall2_wall,
         "/redir/index.html": route_redir_index,
         "/redir/go.php": route_redir_go,
         "/redir/target.html": route_redir_target,