r546 - trunk/openbios-devel/modules

Author: laurent
Date: 2009-08-10 22:18:27 +0200 (Mon, 10 Aug 2009)
New Revision: 546

Modified:
   trunk/openbios-devel/modules/disk-label.c
Log:
This patch modifies disk-label.c to not allow to read beyond 
the selected partition limits.

Signed-off-by: Laurent Vivier

Modified: trunk/openbios-devel/modules/disk-label.c
===================================================================
--- trunk/openbios-devel/modules/disk-label.c	2009-08-10 19:57:43 UTC (rev 545)
+++ trunk/openbios-devel/modules/disk-label.c	2009-08-10 20:18:27 UTC (rev 546)
@@ -99,8 +99,8 @@
    	if( ph ) {
    		di->offs_hi = 0;
    		di->offs_lo = 0;
-			di->size_hi = -1;
-			di->size_lo = -1;
+			di->size_hi = 0;
+			di->size_lo = 0;
    		di->part_ih = 0;
    		di->type = -1;
    		di->block_size = 512;
@@ -174,7 +174,14 @@
 {
    int ret, len = POP();
    char *buf = (char*)POP();
+	llong pos = tell( di->fd );
+	ducell offs = ((ducell)di->offs_hi << BITS) | di->offs_lo;
+	ducell size = ((ducell)di->size_hi << BITS) | di->size_lo;

+	if (size && len > pos - offs + size) {
+		len = size - (pos - offs);
+	}
+
    ret = read_io( di->fd, buf, len );
    PUSH( ret );
 }
@@ -188,6 +195,7 @@
    ducell offs = ((ducell)di->offs_hi << BITS) | di->offs_lo;
    ducell size = ((ducell)di->size_hi << BITS) | di->size_lo;

+	DPRINTF("dlabel_seek %llx [%llx, %llx]\n", pos, offs, size);
    if( pos != -1 )
    	pos += offs;
    else if( size ) {
@@ -196,8 +204,12 @@
    } else {
    	/* let parent handle the EOF seek. */
    }
+	DPRINTF("dlabel_seek: 0x%llx\n", pos );
+	if (size && (pos - offs >= size )) {
+		PUSH(-1);
+		return;
+	}

-	DPRINTF("dlabel_seek: %x %08x\n", (int)(pos>>32), (int)pos );
    ret = seek_io( di->fd, pos );
    PUSH( ret );
 }