--- sysctl.c
+++ sysctl.c	2007-12-12 12:05:48.138322148 +0100
@@ -128,6 +128,7 @@ static int ReadSetting(const char *restr
    char *restrict outname;
    char inbuf[1025];
    FILE *restrict fp;
+   struct stat ts;
 
    if (!name || !*name) {
       fprintf(stderr, ERR_INVALID_KEY, name);
@@ -135,7 +136,7 @@ static int ReadSetting(const char *restr
    }
 
    /* used to open the file */
-   tmpname = malloc(strlen(name)+strlen(PROC_PATH)+1);
+   tmpname = malloc(strlen(name)+strlen(PROC_PATH)+2);
    strcpy(tmpname, PROC_PATH);
    strcat(tmpname, name); 
    slashdot(tmpname+strlen(PROC_PATH),'.','/'); /* change . to / */
@@ -144,6 +145,23 @@ static int ReadSetting(const char *restr
    outname = strdup(name);
    slashdot(outname,'/','.'); /* change / to . */
 
+   if (stat(tmpname, &ts) < 0) {
+      perror(tmpname);
+      rc = -1;
+      goto out;
+   }
+   if ((ts.st_mode & S_IRUSR) == 0)
+      goto out;
+
+   if (S_ISDIR(ts.st_mode)) {
+      size_t len;
+      len = strlen(tmpname);
+      tmpname[len] = '/';
+      tmpname[len+1] = '\0';
+      rc = DisplayAll(tmpname);
+      goto out;
+   }
+
    fp = fopen(tmpname, "r");
 
    if (!fp) {
@@ -194,8 +212,9 @@ static int ReadSetting(const char *restr
             len = strlen(tmpname);
             tmpname[len] = '/';
             tmpname[len+1] = '\0';
+            fclose(fp);
             rc = DisplayAll(tmpname);
-            break;
+            goto out;
          }
          default:
             fprintf(stderr, ERR_UNKNOWN_READING, strerror(errno), outname);
@@ -205,7 +224,7 @@ static int ReadSetting(const char *restr
       }
       fclose(fp);
    }
-
+out:
    free(tmpname);
    free(outname);
    return rc;
@@ -265,8 +284,9 @@ static int WriteSetting(const char *sett
    const char *value;
    const char *equals;
    char *tmpname;
-   FILE *fp;
    char *outname;
+   FILE *fp;
+   struct stat ts;
 
    if (!name) {        /* probably don't want to display this err */
       return 0;
@@ -299,6 +319,22 @@ static int WriteSetting(const char *sett
    outname[equals-name] = 0;
    slashdot(outname,'/','.'); /* change / to . */
  
+   if (stat(tmpname, &ts) < 0) {
+      perror(tmpname);
+      rc = -1;
+      goto out;
+   }
+
+   if ((ts.st_mode & S_IWUSR) == 0) {
+      fprintf(stderr, ERR_UNKNOWN_WRITING, strerror(EACCES), outname);
+      goto out;
+   }
+
+   if (S_ISDIR(ts.st_mode)) {
+      fprintf(stderr, ERR_UNKNOWN_WRITING, strerror(EACCES), outname);
+      goto out;
+   }
+
    fp = fopen(tmpname, "w");
 
    if (!fp) {
@@ -343,7 +379,7 @@ static int WriteSetting(const char *sett
          }
       }
    }
-
+out:
    free(tmpname);
    free(outname);
    return rc;