lstat instead of stat can stat even symlink itself, not the file

that it refers to.

diff --git a/crontab.c b/crontab.c
index 3662b462cca2dcbc6319e0f81e0a51b804f79941..1719216f84b38a2aaf0ffbd0175c9b23d6d7c3a5 100644 (file)
--- a/crontab.c
+++ b/crontab.c
@@ -488,7 +488,7 @@ edit_cmd(void) {
        (void)signal(SIGHUP, SIG_DFL);
        (void)signal(SIGINT, SIG_DFL);
        (void)signal(SIGQUIT, SIG_DFL);      
-       if (stat(Filename, &statbuf) < 0) {
+       if (lstat(Filename, &statbuf) < 0) {
                perror("fstat");
                goto fatal;
        }
@@ -497,6 +497,21 @@ edit_cmd(void) {
                        ProgramName);
                goto remove;
        }
+
+       if (  (!S_ISREG(statbuf.st_mode))
+           ||(S_ISLNK(statbuf.st_mode))
+           ||(S_ISDIR(statbuf.st_mode))
+            ||(S_ISCHR(statbuf.st_mode))
+           ||(S_ISBLK(statbuf.st_mode))
+            ||(S_ISFIFO(statbuf.st_mode))
+           ||(S_ISSOCK(statbuf.st_mode))
+           )
+       {
+           fprintf(stderr, "%s: illegal crontab\n",
+                       ProgramName);
+               goto remove;        
+       }
+
        fprintf(stderr, "%s: installing new crontab\n", ProgramName);
         fclose(NewCrontab);
        NewCrontab=fopen(Filename,"r+");