1 files changed, 13 insertions, 2 deletions

diff --git a/fs/char_dev.c b/fs/char_dev.c
index c1e3537909fc..a69a5d8a406f 100644
--- a/fs/char_dev.c
+++ b/fs/char_dev.c
@@ -56,10 +56,21 @@ int get_chrdev_list(char *page)
 
         down(&chrdevs_lock);
         for (i = 0; i < ARRAY_SIZE(chrdevs) ; i++) {
-                for (cd = chrdevs[i]; cd; cd = cd->next)
+                for (cd = chrdevs[i]; cd; cd = cd->next) {
+                        /*
+                         * if the current name, plus the 5 extra characters
+                         * in the device line for this entry
+                         * would run us off the page, we're done
+                         */
+                        if ((len+strlen(cd->name) + 5) >= PAGE_SIZE)
+                                goto page_full;
+
+
                         len += sprintf(page+len, "%3d %s\n",
                                        cd->major, cd->name);
+                }
         }
+page_full:
         up(&chrdevs_lock);
 
         return len;
@@ -139,7 +150,7 @@ __unregister_chrdev_region(unsigned major, unsigned baseminor, int minorct)
         struct char_device_struct *cd = NULL, **cp;
         int i = major_to_index(major);
 
-        up(&chrdevs_lock);
+        down(&chrdevs_lock);
         for (cp = &chrdevs[i]; *cp; cp = &(*cp)->next)
                 if ((*cp)->major == major &&
                     (*cp)->baseminor == baseminor &&