From: Thomas Veerman <thomas@minix3.org>
Date: Mon, 16 Jan 2012 15:09:55 +0000 (+0000)
Subject: lseek should not yield a negative file position
X-Git-Tag: v3.2.0~111
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/invmod.png?a=commitdiff_plain;h=700641afb86c7615377fa78b5df448ffaaa50c0f;p=minix.git

lseek should not yield a negative file position
---

diff --git a/servers/avfs/open.c b/servers/avfs/open.c
index a236107fd..e3cbf4470 100644
--- a/servers/avfs/open.c
+++ b/servers/avfs/open.c
@@ -612,9 +612,11 @@ PUBLIC int do_lseek()
 	newpos = sub64ul(pos, -offset);
 
   /* Check for overflow. */
-  if (ex64hi(newpos) != 0)
-	r = EINVAL;
-  else {
+  if (ex64hi(newpos) != 0) {
+	r = EOVERFLOW;
+  } else if ((off_t) ex64lo(newpos) < 0) { /* no negative file size */
+	r = EOVERFLOW;
+  } else {
 	rfilp->filp_pos = newpos;
 
 	/* insert the new position into the output message */