File curl-CVE-2020-8285.patch of Package curl.28982

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File curl-CVE-2020-8285.patch of Package curl.28982

From c11171033d5eb8e6514bbabd49c710e0b9885e6f Mon Sep 17 00:00:00 2001
From: Daniel Stenberg <daniel@haxx.se>
Date: Sat, 28 Nov 2020 00:27:21 +0100
Subject: [PATCH] ftp: make wc_statemach loop instead of recurse

---
 lib/ftp.c | 202 +++++++++++++++++++++++++++---------------------------
 1 file changed, 102 insertions(+), 100 deletions(-)

Index: curl-7.37.0/lib/ftp.c
===================================================================
--- curl-7.37.0.orig/lib/ftp.c
+++ curl-7.37.0/lib/ftp.c
@@ -3890,123 +3890,123 @@ static CURLcode init_wc_data(struct conn
   return CURLE_OK;
 }
 
-/* This is called recursively */
 static CURLcode wc_statemach(struct connectdata *conn)
 {
   struct WildcardData * const wildcard = &(conn->data->wildcard);
-  CURLcode ret = CURLE_OK;
+  CURLcode result = CURLE_OK;
 
-  switch (wildcard->state) {
-  case CURLWC_INIT:
-    ret = init_wc_data(conn);
-    if(wildcard->state == CURLWC_CLEAN)
-      /* only listing! */
-      break;
-    else
-      wildcard->state = ret ? CURLWC_ERROR : CURLWC_MATCHING;
-    break;
-
-  case CURLWC_MATCHING: {
-    /* In this state is LIST response successfully parsed, so lets restore
-       previous WRITEFUNCTION callback and WRITEDATA pointer */
-    struct ftp_wc_tmpdata *ftp_tmp = wildcard->tmp;
-    conn->data->set.fwrite_func = ftp_tmp->backup.write_function;
-    conn->data->set.out = ftp_tmp->backup.file_descriptor;
-    ftp_tmp->backup.write_function = ZERO_NULL;
-    ftp_tmp->backup.file_descriptor = NULL;
-    wildcard->state = CURLWC_DOWNLOADING;
-
-    if(Curl_ftp_parselist_geterror(ftp_tmp->parser)) {
-      /* error found in LIST parsing */
-      wildcard->state = CURLWC_CLEAN;
-      return wc_statemach(conn);
-    }
-    else if(wildcard->filelist->size == 0) {
-      /* no corresponding file */
-      wildcard->state = CURLWC_CLEAN;
-      return CURLE_REMOTE_FILE_NOT_FOUND;
+  for(;;) {
+    switch(wildcard->state) {
+    case CURLWC_INIT:
+      result = init_wc_data(conn);
+      if(wildcard->state == CURLWC_CLEAN)
+        /* only listing! */
+        return result;
+      wildcard->state = result ? CURLWC_ERROR : CURLWC_MATCHING;
+      return result;
+
+    case CURLWC_MATCHING: {
+      /* In this state is LIST response successfully parsed, so lets restore
+         previous WRITEFUNCTION callback and WRITEDATA pointer */
+      struct ftp_wc_tmpdata *ftpwc = wildcard->tmp;
+      conn->data->set.fwrite_func = ftpwc->backup.write_function;
+      conn->data->set.out = ftpwc->backup.file_descriptor;
+      ftpwc->backup.write_function = ZERO_NULL;
+      ftpwc->backup.file_descriptor = NULL;
+      wildcard->state = CURLWC_DOWNLOADING;
+
+      if(Curl_ftp_parselist_geterror(ftpwc->parser)) {
+        /* error found in LIST parsing */
+        wildcard->state = CURLWC_CLEAN;
+        continue;
+      }
+      if(wildcard->filelist->size == 0) {
+        /* no corresponding file */
+        wildcard->state = CURLWC_CLEAN;
+        return CURLE_REMOTE_FILE_NOT_FOUND;
+      }
+      continue;
     }
-    return wc_statemach(conn);
-  }
 
-  case CURLWC_DOWNLOADING: {
-    /* filelist has at least one file, lets get first one */
-    struct ftp_conn *ftpc = &conn->proto.ftpc;
-    struct curl_fileinfo *finfo = wildcard->filelist->head->ptr;
-
-    char *tmp_path = aprintf("%s%s", wildcard->path, finfo->filename);
-    if(!tmp_path)
-      return CURLE_OUT_OF_MEMORY;
-
-    /* switch default "state.pathbuffer" and tmp_path, good to see
-       ftp_parse_url_path function to understand this trick */
-    Curl_safefree(conn->data->state.pathbuffer);
-    conn->data->state.pathbuffer = tmp_path;
-    conn->data->state.path = tmp_path;
-
-    infof(conn->data, "Wildcard - START of \"%s\"\n", finfo->filename);
-    if(conn->data->set.chunk_bgn) {
-      long userresponse = conn->data->set.chunk_bgn(
+    case CURLWC_DOWNLOADING: {
+      /* filelist has at least one file, lets get first one */
+      struct ftp_conn *ftpc = &conn->proto.ftpc;
+      struct curl_fileinfo *finfo = wildcard->filelist->head->ptr;
+
+      char *tmp_path = aprintf("%s%s", wildcard->path, finfo->filename);
+      if(!tmp_path)
+        return CURLE_OUT_OF_MEMORY;
+
+      /* switch default "state.pathbuffer" and tmp_path, good to see
+         ftp_parse_url_path function to understand this trick */
+	  Curl_safefree(conn->data->state.pathbuffer);
+      conn->data->state.pathbuffer = tmp_path;
+      conn->data->state.path = tmp_path;
+
+      infof(conn->data, "Wildcard - START of \"%s\"\n", finfo->filename);
+      if(conn->data->set.chunk_bgn) {
+        long userresponse = conn->data->set.chunk_bgn(
           finfo, wildcard->customptr, (int)wildcard->filelist->size);
-      switch(userresponse) {
-      case CURL_CHUNK_BGN_FUNC_SKIP:
-        infof(conn->data, "Wildcard - \"%s\" skipped by user\n",
-              finfo->filename);
+        switch(userresponse) {
+        case CURL_CHUNK_BGN_FUNC_SKIP:
+          infof(conn->data, "Wildcard - \"%s\" skipped by user\n",
+                finfo->filename);
+          wildcard->state = CURLWC_SKIP;
+          continue;
+        case CURL_CHUNK_BGN_FUNC_FAIL:
+          return CURLE_CHUNK_FAILED;
+        }
+	  }
+
+     if(finfo->filetype != CURLFILETYPE_FILE) {
         wildcard->state = CURLWC_SKIP;
-        return wc_statemach(conn);
-      case CURL_CHUNK_BGN_FUNC_FAIL:
-        return CURLE_CHUNK_FAILED;
+        continue;
       }
-    }
-
-    if(finfo->filetype != CURLFILETYPE_FILE) {
-      wildcard->state = CURLWC_SKIP;
-      return wc_statemach(conn);
-    }
 
-    if(finfo->flags & CURLFINFOFLAG_KNOWN_SIZE)
-      ftpc->known_filesize = finfo->size;
+      if(finfo->flags & CURLFINFOFLAG_KNOWN_SIZE)
+        ftpc->known_filesize = finfo->size;
 
-    ret = ftp_parse_url_path(conn);
-    if(ret) {
-      return ret;
-    }
-
-    /* we don't need the Curl_fileinfo of first file anymore */
-    Curl_llist_remove(wildcard->filelist, wildcard->filelist->head, NULL);
-
-    if(wildcard->filelist->size == 0) { /* remains only one file to down. */
-      wildcard->state = CURLWC_CLEAN;
-      /* after that will be ftp_do called once again and no transfer
-         will be done because of CURLWC_CLEAN state */
-      return CURLE_OK;
-    }
-  } break;
-
-  case CURLWC_SKIP: {
-    if(conn->data->set.chunk_end)
-      conn->data->set.chunk_end(conn->data->wildcard.customptr);
-    Curl_llist_remove(wildcard->filelist, wildcard->filelist->head, NULL);
-    wildcard->state = (wildcard->filelist->size == 0) ?
-                      CURLWC_CLEAN : CURLWC_DOWNLOADING;
-    return wc_statemach(conn);
-  }
+      result = ftp_parse_url_path(conn);
+      if(result)
+        return result;
+
+      /* we don't need the Curl_fileinfo of first file anymore */
+      Curl_llist_remove(wildcard->filelist, wildcard->filelist->head, NULL);
+
+      if(wildcard->filelist->size == 0) { /* remains only one file to down. */
+        wildcard->state = CURLWC_CLEAN;
+        /* after that will be ftp_do called once again and no transfer
+           will be done because of CURLWC_CLEAN state */
+        return CURLE_OK;
+      }
+      return result;
+	}
 
-  case CURLWC_CLEAN: {
-    struct ftp_wc_tmpdata *ftp_tmp = wildcard->tmp;
-    ret = CURLE_OK;
-    if(ftp_tmp) {
-      ret = Curl_ftp_parselist_geterror(ftp_tmp->parser);
+    case CURLWC_SKIP: {
+      if(conn->data->set.chunk_end)
+        conn->data->set.chunk_end(conn->data->wildcard.customptr);
+      Curl_llist_remove(wildcard->filelist, wildcard->filelist->head, NULL);
+      wildcard->state = (wildcard->filelist->size == 0) ?
+                         CURLWC_CLEAN : CURLWC_DOWNLOADING;
+      continue;
+    }
+
+    case CURLWC_CLEAN: {
+      struct ftp_wc_tmpdata *ftpwc = wildcard->tmp;
+      result = CURLE_OK;
+      if(ftpwc)
+        result = Curl_ftp_parselist_geterror(ftpwc->parser);
+
+      wildcard->state = result ? CURLWC_ERROR : CURLWC_DONE;
+      return result;
+    }
+
+    case CURLWC_DONE:
+    case CURLWC_ERROR:
+      return result;
     }
-    wildcard->state = ret ? CURLWC_ERROR : CURLWC_DONE;
-  } break;
-
-  case CURLWC_DONE:
-  case CURLWC_ERROR:
-    break;
   }
-
-  return ret;
+  /* UNREACHABLE */
 }
 
 /***********************************************************************

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File curl-CVE-2020-8285.patch of Package curl.28982

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