diff --git a/docs/cmdline-opts/data.md b/docs/cmdline-opts/data.md
index 71dd36e046..ebe2347d86 100644
--- a/docs/cmdline-opts/data.md
+++ b/docs/cmdline-opts/data.md
@@ -40,8 +40,8 @@ data pieces specified are merged with a separating &-symbol. Thus, using
 If you start the data with the letter @, the rest should be a filename to read
 the data from, or - if you want curl to read the data from stdin. Posting data
 from a file named 'foobar' would thus be done with --data @foobar. When --data
-is told to read from a file like that, carriage returns and newlines are
-stripped out. If you do not want the @ character to have a special
+is told to read from a file like that, carriage returns, newlines and null
+bytes are stripped out. If you do not want the @ character to have a special
 interpretation use --data-raw instead.
 
 The data for this option is passed on to the server exactly as provided on the
diff --git a/src/tool_paramhlp.c b/src/tool_paramhlp.c
index 2725815000..c26f6bbefd 100644
--- a/src/tool_paramhlp.c
+++ b/src/tool_paramhlp.c
@@ -63,6 +63,33 @@ struct getout *new_getout(struct OperationConfig *config)
   return node;
 }
 
+#define ISCRLF(x) (((x) == '\r') || ((x) == '\n') || ((x) == '\0'))
+
+/* memcrlf() has two modes. Both operate on a given memory area with
+   a specified size.
+
+   countcrlf FALSE - return number of bytes from the start that DO NOT include
+   any CR or LF or NULL
+
+   countcrlf TRUE - return number of bytes from the start that are ONLY CR or
+   LF or NULL.
+
+*/
+static size_t memcrlf(char *orig,
+                      bool countcrlf, /* TRUE if we count CRLF, FALSE
+                                         if we count non-CRLF */
+                      size_t max)
+{
+  char *ptr = orig;
+  size_t total = max;
+  for(ptr = orig; max; max--, ptr++) {
+    bool crlf = ISCRLF(*ptr);
+    if(countcrlf ^ crlf)
+      return ptr - orig;
+  }
+  return total; /* no delimiter found */
+}
+
 #define MAX_FILE2STRING (256*1024*1024) /* big enough ? */
 
 ParameterError file2string(char **bufp, FILE *file)
@@ -71,18 +98,30 @@ ParameterError file2string(char **bufp, FILE *file)
   DEBUGASSERT(MAX_FILE2STRING < INT_MAX); /* needs to fit in an int later */
   curlx_dyn_init(&dyn, MAX_FILE2STRING);
   if(file) {
-    char buffer[256];
+    do {
+      char buffer[4096];
+      char *ptr;
+      size_t nread = fread(buffer, 1, sizeof(buffer), file);
+      if(ferror(file)) {
+        curlx_dyn_free(&dyn);
+        *bufp = NULL;
+        return PARAM_READ_ERROR;
+      }
+      ptr = buffer;
+      while(nread) {
+        size_t nlen = memcrlf(ptr, FALSE, nread);
+        if(curlx_dyn_addn(&dyn, ptr, nlen))
+          return PARAM_NO_MEM;
+        nread -= nlen;
 
-    while(fgets(buffer, sizeof(buffer), file)) {
-      char *ptr = strchr(buffer, '\r');
-      if(ptr)
-        *ptr = '\0';
-      ptr = strchr(buffer, '\n');
-      if(ptr)
-        *ptr = '\0';
-      if(curlx_dyn_add(&dyn, buffer))
-        return PARAM_NO_MEM;
-    }
+        if(nread) {
+          ptr += nlen;
+          nlen = memcrlf(ptr, TRUE, nread);
+          ptr += nlen;
+          nread -= nlen;
+        }
+      }
+    } while(!feof(file));
   }
   *bufp = curlx_dyn_ptr(&dyn);
   return PARAM_OK;