[src/netbsd-1-4]: src/sys/msdosfs Pull up revision 1.96 (requested by jdolecek):

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

details:   https://anonhg.NetBSD.org/src/rev/2c596684497f
branches:  netbsd-1-4
changeset: 470539:2c596684497f
user:      he <he%NetBSD.org@localhost>
date:      Sun Apr 30 13:13:03 2000 +0000

description:
Pull up revision 1.96 (requested by jdolecek):
  Avoid integer overflow preventing reading of files >2GB in size.
  Fixes PR#9046.

diffstat:

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

diffs (34 lines):

diff -r 8a08c4216aa5 -r 2c596684497f sys/msdosfs/msdosfs_vnops.c
--- a/sys/msdosfs/msdosfs_vnops.c       Sun Apr 30 13:11:22 2000 +0000
+++ b/sys/msdosfs/msdosfs_vnops.c       Sun Apr 30 13:13:03 2000 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: msdosfs_vnops.c,v 1.79.2.6 2000/02/04 23:00:17 he Exp $        */
+/*     $NetBSD: msdosfs_vnops.c,v 1.79.2.7 2000/04/30 13:13:03 he Exp $        */
 
 /*-
  * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
@@ -464,7 +464,7 @@
                struct ucred *a_cred;
        } */ *ap = v;
        int error = 0;
-       int diff;
+       int64_t diff;
        int blsize;
        int isadir;
        long n;
@@ -490,11 +490,12 @@
                lbn = de_cluster(pmp, uio->uio_offset);
                on = uio->uio_offset & pmp->pm_crbomask;
                n = min((u_long) (pmp->pm_bpcluster - on), uio->uio_resid);
-               diff = dep->de_FileSize - uio->uio_offset;
-               if (diff <= 0)
+               if (uio->uio_offset >= dep->de_FileSize)
                        return (0);
+               /* file size (and hence diff) may be up to 4GB */
+               diff = dep->de_FileSize - uio->uio_offset;
                if (diff < n)
-                       n = diff;
+                       n = (long) diff;
                /* convert cluster # to block # if a directory */
                if (isadir) {
                        error = pcbmap(dep, lbn, &lbn, 0, &blsize);