--- a/src/encode.c
+++ b/src/encode.c
@@ -194,10 +194,12 @@ int encode_init(void) {
 
 char *pr_decode_str(pool *p, const char *in, size_t inlen, size_t *outlen) {
 #ifdef HAVE_ICONV
-  size_t inbuflen, outbuflen;
+  size_t inbuflen, outbuflen, outbufsz;
   char *inbuf, outbuf[PR_TUNABLE_PATH_MAX*2], *res = NULL;
 
-  if (!p || !in || !outlen) {
+  if (p == NULL ||
+      in == NULL ||
+      outlen == NULL) {
     errno = EINVAL;
     return NULL;
   }
@@ -229,7 +231,11 @@ char *pr_decode_str(pool *p, const char *in, size_t inlen, size_t *outlen) {
     return NULL;
 
   *outlen = sizeof(outbuf) - outbuflen;
-  res = pcalloc(p, *outlen);
+
+  /* We allocate one byte more, for a terminating NUL. */
+  outbufsz = sizeof(outbuf) - outbuflen + 1;
+  res = pcalloc(p, outbufsz);
+
   memcpy(res, outbuf, *outlen);
 
   return res;
@@ -242,10 +248,12 @@ char *pr_decode_str(pool *p, const char *in, size_t inlen, size_t *outlen) {
 
 char *pr_encode_str(pool *p, const char *in, size_t inlen, size_t *outlen) {
 #ifdef HAVE_ICONV
-  size_t inbuflen, outbuflen;
+  size_t inbuflen, outbuflen, outbufsz;
   char *inbuf, outbuf[PR_TUNABLE_PATH_MAX*2], *res;
 
-  if (!p || !in || !outlen) {
+  if (p == NULL ||
+      in == NULL ||
+      outlen == NULL) {
     errno = EINVAL;
     return NULL;
   }
@@ -277,7 +285,11 @@ char *pr_encode_str(pool *p, const char *in, size_t inlen, size_t *outlen) {
     return NULL;
 
   *outlen = sizeof(outbuf) - outbuflen;
-  res = pcalloc(p, *outlen);
+
+  /* We allocate one byte more, for a terminating NUL. */
+  outbufsz = sizeof(outbuf) - outbuflen + 1;
+
+  res = pcalloc(p, outbufsz);
   memcpy(res, outbuf, *outlen);
 
   return res;
diff --git a/src/fsio.c b/src/fsio.c
index 40ef466..8bf5069 100644
--- a/src/fsio.c
+++ b/src/fsio.c
@@ -2058,7 +2058,7 @@ char *pr_fs_decode_path(pool *p, const char *path) {
     return (char *) path;
   }
 
-  res = pr_decode_str(p, path, strlen(path) + 1, &outlen);
+  res = pr_decode_str(p, path, strlen(path), &outlen);
   if (!res) {
     pr_trace_msg("encode", 1, "error decoding path '%s': %s", path,
       strerror(errno));
@@ -2081,7 +2081,7 @@ char *pr_fs_encode_path(pool *p, const char *path) {
     return (char *) path;
   }
 
-  res = pr_encode_str(p, path, strlen(path) + 1, &outlen);
+  res = pr_encode_str(p, path, strlen(path), &outlen);
   if (!res) {
     pr_trace_msg("encode", 1, "error encoding path '%s': %s", path,
       strerror(errno));