From: Thomas Veerman <thomas@minix3.org>
Date: Fri, 25 Jan 2013 11:57:32 +0000 (+0000)
Subject: PFS: verify nrbytes
X-Git-Tag: v3.2.1~73
X-Git-Url: http://zhaoyanbai.com/repos/%22http:/www.isc.org/icons/zlib_tech.html?a=commitdiff_plain;h=0968a93748baaeb19add58135e369964846c9e4b;p=minix.git

PFS: verify nrbytes
---

diff --git a/servers/pfs/read.c b/servers/pfs/read.c
index 86a4f0b1e..cbbba89a5 100644
--- a/servers/pfs/read.c
+++ b/servers/pfs/read.c
@@ -36,7 +36,7 @@ int fs_readwrite(message *fs_m_in, message *fs_m_out)
   nrbytes = (unsigned) fs_m_in->REQ_NBYTES;
 
   /* We can't read beyond the max file position */
-  if (nrbytes > MAX_FILE_POS) return(EFBIG);
+  if (nrbytes > PIPE_BUF) return(EFBIG);
 
   /* Mark inode in use */
   if ((get_inode(rip->i_dev, rip->i_num)) == NULL) return(err_code);
@@ -48,7 +48,7 @@ int fs_readwrite(message *fs_m_in, message *fs_m_out)
 	 * be beyond max signed value (i.e., MAX_FILE_POS).
 	 */
 	position = rip->i_size;
-	if (position > PIPE_BUF - (signed) nrbytes) {
+	if ((unsigned) position + nrbytes > PIPE_BUF) {
 		put_inode(rip);
 		put_block(rip->i_dev, rip->i_num);
 		return(EFBIG);