Changeset 3654:9eb775ff3c55

Timestamp:

2004-04-12 14:43:32 (5 years ago)

Author:

Thomas Roessler <roessler@…>

Branch:

HEAD

Message:

Don't open a file for writing that we have unlinked before. Reported
embarassingly long ago by Jarno Huuskonen <Jarno.Huuskonen@…>.

Files:

• attach.c (modified) (4 diffs)
• lib.c (modified) (1 diff)

attach.c

@@ -109 +109 @@
             goto bailout;
         }
-        unlink_newfile = 1;
+        else
+          unlink_newfile = 1;
       }
       else
@@ -174 +175 @@
             fclose (tfp);
             mutt_unlink (a->filename);  
-            mutt_rename_file (tempfile, a->filename); 
+            if (mutt_rename_file (tempfile, a->filename) != 0) 
+            {
+              mutt_perror _("Failure to rename file.");
+              goto bailout;
+            }
 
             mutt_free_body (&b);
@@ -236 +241 @@
             goto bailout;
         }
-        unlink_newfile = 1;
+        else
+          unlink_newfile = 1;
       }
       else
@@ -608 +614 @@
     rc = mutt_do_pager (descrip, pagerfile,
                         M_PAGER_ATTACHMENT | (is_message ? M_PAGER_MESSAGE : 0), &info);
+    *pagerfile = '\0';
   }
   else

lib.c

@@ -182 +182 @@
 void mutt_unlink (const char *s)
 {
+  int fd;
+  int flags;
   FILE *f;
   struct stat sb;
   char buf[2048];
+
+  /* Defend against symlink attacks */
+  
+#ifdef O_NOFOLLOW 
+  flags = O_RDWR | O_NOFOLLOW;
+#else
+  flags = O_RDWR;
+#endif
   
   if (stat (s, &sb) == 0)
   {
-    if ((f = fopen (s, "r+")))
+    if ((fd = open (s, flags)) < 0)
+      return;
+    if ((f = fdopen (fd, "r+")))
     {
       unlink (s);