[src/trunk]: src/sys/kern do_posix_fadvise: check for a negative length; trun...

[rmind <rmind%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/b2e3b91bcbc0
branches:  trunk
changeset: 758215:b2e3b91bcbc0
user:      rmind <rmind%NetBSD.org@localhost>
date:      Wed Oct 27 02:58:04 2010 +0000

description:
do_posix_fadvise: check for a negative length; truncate the offset and
round the end-offset, not vice-versa.

Thanks to jakllsch@ for debug info.

diffstat:

 sys/kern/sys_descrip.c |  11 ++++++-----
 1 files changed, 6 insertions(+), 5 deletions(-)

diffs (45 lines):

diff -r a1296b8cb31d -r b2e3b91bcbc0 sys/kern/sys_descrip.c
--- a/sys/kern/sys_descrip.c    Tue Oct 26 22:34:33 2010 +0000
+++ b/sys/kern/sys_descrip.c    Wed Oct 27 02:58:04 2010 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: sys_descrip.c,v 1.17 2009/10/28 18:24:44 njoly Exp $   */
+/*     $NetBSD: sys_descrip.c,v 1.18 2010/10/27 02:58:04 rmind Exp $   */
 
 /*-
  * Copyright (c) 2008 The NetBSD Foundation, Inc.
@@ -67,7 +67,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: sys_descrip.c,v 1.17 2009/10/28 18:24:44 njoly Exp $");
+__KERNEL_RCSID(0, "$NetBSD: sys_descrip.c,v 1.18 2010/10/27 02:58:04 rmind Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -622,13 +622,14 @@
        vnode_t *vp;
        off_t endoffset;
        int error;
+
        CTASSERT(POSIX_FADV_NORMAL == UVM_ADV_NORMAL);
        CTASSERT(POSIX_FADV_RANDOM == UVM_ADV_RANDOM);
        CTASSERT(POSIX_FADV_SEQUENTIAL == UVM_ADV_SEQUENTIAL);
 
        if (len == 0) {
                endoffset = INT64_MAX;
-       } else if (INT64_MAX - offset >= len) {
+       } else if (len > 0 && (INT64_MAX - offset) >= len) {
                endoffset = offset + len;
        } else {
                return EINVAL;
@@ -680,8 +681,8 @@
        case POSIX_FADV_DONTNEED:
                vp = fp->f_data;
                mutex_enter(&vp->v_interlock);
-               error = VOP_PUTPAGES(vp, round_page(offset),
-                   trunc_page(endoffset), PGO_DEACTIVATE | PGO_CLEANIT);
+               error = VOP_PUTPAGES(vp, trunc_page(offset),
+                   round_page(endoffset), PGO_DEACTIVATE | PGO_CLEANIT);
                break;
 
        case POSIX_FADV_NOREUSE: