[PATCH] Linux kernels DoSable by file-max limit

[PATCH] Linux kernels DoSable by file-max limit

[elv]

hi, 

in the previous patch a line was missed 

 --- ../patches/linux/fs/file_table.c	Mon Sep 17 20:16:30 2001
+++ fs/file_table.c	Thu Jul 11 19:01:40 2002
@@ -51,9 +51,13 @@
		return f;
	}
	/*
 -	 * Use a reserved one if we're the superuser
+	 * Use one of the first 16 reserved fds if we have euid == 0
+	 * and one of the second 16 reserved fds if we're the superuser
	 */
 -	if (files_stat.nr_free_files && !current->euid)
+	if (files_stat.nr_free_files > NR_RESERVED_FILES/2 && !current->euid)
+		goto used_one;
+	else if (files_stat.nr_free_files <= NR_RESERVED_FILES/2 && !current->uid
+		&& files_stat.nr_free_files != 0)
		goto used_one;
	/*
	 * Allocate a new one if we're below the limit. 


 --- /usr/src/linux/include/linux/fs.h   Mon Jul  1 14:48:44 2002
+++ /usr/src/linux/include/linux/fs.h   Tue Jul  9 00:07:06 2002
@@ -65,7 +65,7 @@
extern int leases_enable, dir_notify_enable, lease_break_time; 

#define NR_FILE  8192   /* this can well be larger on a larger system */
 -#define NR_RESERVED_FILES 10 /* reserved for root */
+#define NR_RESERVED_FILES 32 /* first 16 for euid == 0 processes and second 
16 only for root */
#define NR_SUPER 256 

#define MAY_EXEC 1 


elv