From mboxrd@z Thu Jan  1 00:00:00 1970
From: Roel Kluin <roel.kluin@gmail.com>
Subject: [PATCH] ide-cd: unsigned len subtracted below 0?
Date: Wed, 04 Mar 2009 00:13:46 +0100
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To: Borislav Petkov <petkovbb@gmail.com>
Cc: linux-ide@vger.kernel.org, Andrew Morton <akpm@linux-foundation.org>

len is unsigned, so take care not to subtract below 0.

Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
---
diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c
index ddfbea4..23447a0 100644
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -916,7 +916,10 @@ static ide_startstop_t cdrom_newpc_intr(ide_drive_t *drive)
 		xferfunc(drive, NULL, ptr, blen);
 
 		thislen -= blen;
-		len -= blen;
+		if (blen > len)
+			len -= blen;
+		else
+			len = 0;
 
 		if (blk_fs_request(rq)) {
 			rq->buffer += blen;