[src/trunk]: src/sys/compat/common - don't use MALLOC for non constant counts

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

details:   https://anonhg.NetBSD.org/src/rev/2f044adb6de3
branches:  trunk
changeset: 555505:2f044adb6de3
user:      christos <christos%NetBSD.org@localhost>
date:      Wed Nov 19 16:43:38 2003 +0000

description:
- don't use MALLOC for non constant counts
- check malloc() size.

diffstat:

 sys/compat/common/vfs_syscalls_43.c |  25 ++++++++++++++-----------
 1 files changed, 14 insertions(+), 11 deletions(-)

diffs (105 lines):

diff -r 2801cf776ce9 -r 2f044adb6de3 sys/compat/common/vfs_syscalls_43.c
--- a/sys/compat/common/vfs_syscalls_43.c       Wed Nov 19 15:48:21 2003 +0000
+++ b/sys/compat/common/vfs_syscalls_43.c       Wed Nov 19 16:43:38 2003 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vfs_syscalls_43.c,v 1.26 2003/11/19 15:48:21 christos Exp $    */
+/*     $NetBSD: vfs_syscalls_43.c,v 1.27 2003/11/19 16:43:38 christos Exp $    */
 
 /*
  * Copyright (c) 1989, 1993
@@ -37,7 +37,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vfs_syscalls_43.c,v 1.26 2003/11/19 15:48:21 christos Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vfs_syscalls_43.c,v 1.27 2003/11/19 16:43:38 christos Exp $");
 
 #if defined(_KERNEL_OPT)
 #include "fs_union.h"
@@ -55,6 +55,7 @@
 #include <sys/socket.h>
 #include <sys/socketvar.h>
 #include <sys/stat.h>
+#include <sys/malloc.h>
 #include <sys/ioctl.h>
 #include <sys/fcntl.h>
 #include <sys/syslog.h>
@@ -359,6 +360,8 @@
        struct iovec aiov, kiov;
        struct dirent *dp, *edp;
        caddr_t dirbuf;
+       size_t count = min(MAXBSIZE, (size_t)SCARG(uap, count));
+
        int error, eofflag, readcnt;
        long loff;
 
@@ -376,13 +379,13 @@
                goto out;
        }
        aiov.iov_base = SCARG(uap, buf);
-       aiov.iov_len = SCARG(uap, count);
+       aiov.iov_len = count;
        auio.uio_iov = &aiov;
        auio.uio_iovcnt = 1;
        auio.uio_rw = UIO_READ;
        auio.uio_segflg = UIO_USERSPACE;
        auio.uio_procp = p;
-       auio.uio_resid = SCARG(uap, count);
+       auio.uio_resid = count;
        vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
        loff = auio.uio_offset = fp->f_offset;
 #      if (BYTE_ORDER != LITTLE_ENDIAN)
@@ -396,14 +399,14 @@
                kuio = auio;
                kuio.uio_iov = &kiov;
                kuio.uio_segflg = UIO_SYSSPACE;
-               kiov.iov_len = SCARG(uap, count);
-               MALLOC(dirbuf, caddr_t, SCARG(uap, count), M_TEMP, M_WAITOK);
+               kiov.iov_len = count;
+               dirbuf = malloc(count, M_TEMP, M_WAITOK);
                kiov.iov_base = dirbuf;
                error = VOP_READDIR(vp, &kuio, fp->f_cred, &eofflag,
                            (off_t **)0, (int *)0);
                fp->f_offset = kuio.uio_offset;
                if (error == 0) {
-                       readcnt = SCARG(uap, count) - kuio.uio_resid;
+                       readcnt = count - kuio.uio_resid;
                        edp = (struct dirent *)&dirbuf[readcnt];
                        for (dp = (struct dirent *)dirbuf; dp < edp; ) {
 #                              if (BYTE_ORDER == LITTLE_ENDIAN)
@@ -434,7 +437,7 @@
                        if (dp >= edp)
                                error = uiomove(dirbuf, readcnt, &auio);
                }
-               FREE(dirbuf, M_TEMP);
+               free(dirbuf, M_TEMP);
        }
        VOP_UNLOCK(vp, 0);
        if (error)
@@ -445,7 +448,7 @@
        extern int (**union_vnodeop_p) __P((void *));
        extern struct vnode *union_dircache __P((struct vnode *));
 
-       if ((SCARG(uap, count) == auio.uio_resid) &&
+       if ((count == auio.uio_resid) &&
            (vp->v_op == union_vnodeop_p)) {
                struct vnode *lvp;
 
@@ -484,7 +487,7 @@
 }
 #endif /* UNION */
 
-       if ((SCARG(uap, count) == auio.uio_resid) &&
+       if ((count == auio.uio_resid) &&
            (vp->v_flag & VROOT) &&
            (vp->v_mount->mnt_flag & MNT_UNION)) {
                struct vnode *tvp = vp;
@@ -497,7 +500,7 @@
        }
        error = copyout((caddr_t)&loff, (caddr_t)SCARG(uap, basep),
            sizeof(long));
-       *retval = SCARG(uap, count) - auio.uio_resid;
+       *retval = count - auio.uio_resid;
  out:
        FILE_UNUSE(fp, p);
        return (error);