From: Sage Weil <sage@newdream.net>
Date: Mon, 21 Sep 2009 20:00:27 +0000 (-0400)
Subject: Btrfs: fix arithmetic error in clone ioctl
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=1fb58a6051cd904a9f8e0344b22e31921d6b5a4d;p=GitHub%2FLineageOS%2Fandroid_kernel_samsung_universal7580.git

Btrfs: fix arithmetic error in clone ioctl

Fix an arithmetic error that was breaking extents cloned via the clone
ioctl starting in the second half of a file.

Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
---

diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index a13fd556db7..a8577a7f26a 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1105,8 +1105,7 @@ static noinline long btrfs_ioctl_clone(struct file *file, unsigned long srcfd,
 					datao += off - key.offset;
 					datal -= off - key.offset;
 				}
-				if (key.offset + datao + datal + key.offset >
-				    off + len)
+				if (key.offset + datao + datal > off + len)
 					datal = off + len - key.offset - datao;
 				/* disko == 0 means it's a hole */
 				if (!disko)