Change command line to 511 characters; 1023 caused .bss overrunssyslinux-3.09-pre2

3 files changed, 6 insertions, 4 deletions

diff --git a/NEWS b/NEWS
index e92151fb..e6197e45 100644
--- a/NEWS
+++ b/NEWS
@@ -5,6 +5,8 @@ them.
 Changes in 3.09:
 	* gcc4 compilation fix.
 	* <BEL> (Ctrl-G) in message files now causes a beep.
+	* Reduce the command line to 511 characters; 1023 caused
+	  memory overflows.
 
 Changes in 3.08:
 	* SYSLINUX: Fix performance regression (-s mode always
@@ -24,7 +26,7 @@ Changes in 3.08:
 	  BIOS flash programs.
 	* COM32 module to boot Multiboot systems, including Xen.  See
 	  com32/modules/mboot.doc.
-	* Max command line changed to 1024 characters.  Note that the
+	* Max command line changed to 1023 characters.  Note that the
 	  kernel proper still can only handle 255 characters without
 	  patching, and COM16 binaries can only handle 125 characters.
 
diff --git a/config.inc b/config.inc
index cd83b7d0..bb87f34d 100644
--- a/config.inc
+++ b/config.inc
@@ -20,7 +20,7 @@
 %ifndef _CONFIG_INC
 %define _CONFIG_INC
 
-max_cmd_len	equ 1023		; Must be odd; 255 is the kernel limit
+max_cmd_len	equ 511			; Must be &3; 255 is the kernel limit
 HIGHMEM_MAX	equ 037FFFFFFh		; DEFAULT highest address for an initrd
 DEFAULT_BAUD	equ 9600		; Default baud rate for serial port
 BAUD_DIVISOR	equ 115200		; Serial port parameter
diff --git a/runkernel.inc b/runkernel.inc
index f73998e5..b18ef1a7 100644
--- a/runkernel.inc
+++ b/runkernel.inc
@@ -337,7 +337,7 @@ need_high_cmdline:
 ;
 ; Copy command line up to 90000h
 ;
-		mov ax,9000h
+		mov ax,9000h			; Note AL <- 0
 		mov es,ax
 		mov si,cmd_line_here
 		mov di,si
@@ -350,7 +350,7 @@ need_high_cmdline:
 		mov cx,255			; Protocol < 0x202 has 255 as hard limit
 .len_ok:
 		fs rep movsb
-		fs stosb			; Final null, note AL == 0 here		
+		stosb				; Final null, note AL == 0 already
 
 		push fs
 		pop es