From: Derrick Brashear <shadow@dementia.org>
Date: Fri, 25 Sep 2009 07:15:40 +0000 (-0400)
Subject: viced cap fetchdata len to avoid negative
X-Git-Tag: openafs-stable-1_4_12pre1~124
X-Git-Url: https://git.michaelhowe.org/gitweb/?a=commitdiff_plain;h=dcb60b82fa2e216d02587fe349a4405146661c93;p=packages%2Fo%2Fopenafs.git

viced cap fetchdata len to avoid negative

when trying to read from a short or zero length file,
it's possible for sanity checking to knock the length below
zero. set a floor at zero.

Reviewed-on: http://gerrit.openafs.org/494
Reviewed-by: Jeffrey Altman <jaltman@openafs.org>
Tested-by: Derrick Brashear <shadow@dementia.org>
Reviewed-by: Derrick Brashear <shadow@dementia.org>
(cherry picked from commit 529d487d65d8561f5d0a43a4dc71f72b86efd975)
Reviewed-on: http://gerrit.openafs.org/500
---

diff --git a/src/viced/afsfileprocs.c b/src/viced/afsfileprocs.c
index bf1adc55b..f9080527b 100644
--- a/src/viced/afsfileprocs.c
+++ b/src/viced/afsfileprocs.c
@@ -7087,8 +7087,9 @@ FetchData_RXStyle(Volume * volptr, Vnode * targetptr,
 	Len = 0;
     }
 
-    if (Pos + Len > tlen)
-	Len = tlen - Pos;	/* get length we should send */
+    if (Pos + Len > tlen) /* get length we should send */
+	Len = ((tlen - Pos) < 0) ? 0 : tlen - Pos;
+
     (void)FDH_SEEK(fdP, Pos, 0);
     {
 	afs_int32 high, low;