[src/trunk]: src/sys/compat/netbsd32 Sync getfh() with the native implementat...

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

details:   https://anonhg.NetBSD.org/src/rev/945f3f46d6ed
branches:  trunk
changeset: 796952:945f3f46d6ed
user:      maxv <maxv%NetBSD.org@localhost>
date:      Sat Jun 28 11:39:15 2014 +0000

description:
Sync getfh() with the native implementation. It also fixes:
a) a return value
b) a vnode lock
c) a user-controlled memory allocation

ok christos@, on tech-kern

diffstat:

 sys/compat/netbsd32/netbsd32_netbsd.c |  46 ++++++++++++++++------------------
 1 files changed, 22 insertions(+), 24 deletions(-)

diffs (85 lines):

diff -r 74ec63084339 -r 945f3f46d6ed sys/compat/netbsd32/netbsd32_netbsd.c
--- a/sys/compat/netbsd32/netbsd32_netbsd.c     Sat Jun 28 11:06:31 2014 +0000
+++ b/sys/compat/netbsd32/netbsd32_netbsd.c     Sat Jun 28 11:39:15 2014 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: netbsd32_netbsd.c,v 1.190 2014/06/22 19:09:39 maxv Exp $       */
+/*     $NetBSD: netbsd32_netbsd.c,v 1.191 2014/06/28 11:39:15 maxv Exp $       */
 
 /*
  * Copyright (c) 1998, 2001, 2008 Matthew R. Green
@@ -27,7 +27,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: netbsd32_netbsd.c,v 1.190 2014/06/22 19:09:39 maxv Exp $");
+__KERNEL_RCSID(0, "$NetBSD: netbsd32_netbsd.c,v 1.191 2014/06/28 11:39:15 maxv Exp $");
 
 #if defined(_KERNEL_OPT)
 #include "opt_ddb.h"
@@ -1302,7 +1302,7 @@
        int error;
        struct pathbuf *pb;
        struct nameidata nd;
-       netbsd32_size_t sz32;
+       netbsd32_size_t usz32, sz32;
        size_t sz;
 
        /*
@@ -1312,7 +1312,6 @@
            0, NULL, NULL, NULL);
        if (error)
                return (error);
-       fh = NULL;
 
        error = pathbuf_copyin(SCARG_P32(uap, fname), &pb);
        if (error) {
@@ -1328,30 +1327,29 @@
        vp = nd.ni_vp;
        pathbuf_destroy(pb);
 
-       error = copyin(SCARG_P32(uap, fh_size), &sz32,
-           sizeof(netbsd32_size_t));
-       if (error) {
-               vput(vp);
+       error = vfs_composefh_alloc(vp, &fh);
+       vput(vp);
+       if (error != 0) {
                return error;
        }
-       fh = kmem_alloc(sz32, KM_SLEEP);
-       if (fh == NULL) 
-               return EINVAL;
-       sz = sz32;
-       error = vfs_composefh(vp, fh, &sz);
-       vput(vp);
+       error = copyin(SCARG_P32(uap, fh_size), &usz32, sizeof(usz32));
+       if (error != 0) {
+               goto out;
+       }
+       sz = FHANDLE_SIZE(fh);
+       sz32 = sz;
 
-       if (error == 0) {
-               const netbsd32_size_t nsz32 = sz;
-               error = copyout(&nsz32, SCARG_P32(uap, fh_size),
-                   sizeof(netbsd32_size_t));
-               if (!error) {
-                       error = copyout(fh, SCARG_P32(uap, fhp), sz);
-               }
-       } else if (error == E2BIG) {
-               error = copyout(&sz, SCARG_P32(uap, fh_size), sizeof(size_t));
+       error = copyout(&sz32, SCARG_P32(uap, fh_size), sizeof(sz32));
+       if (error != 0) {
+               goto out;
        }
-       kmem_free(fh, sz32);
+       if (usz32 >= sz32) {
+               error = copyout(fh, SCARG_P32(uap, fhp), sz);
+       } else {
+               error = E2BIG;
+       }
+out:
+       vfs_composefh_free(fh);
        return (error);
 }