[src/trunk]: src/sys Add a new flag, used by vn_open() which prevent symlinks...

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

details:   https://anonhg.NetBSD.org/src/rev/9f8dc4fdd188
branches:  trunk
changeset: 475957:9f8dc4fdd188
user:      bouyer <bouyer%NetBSD.org@localhost>
date:      Tue Aug 31 12:30:35 1999 +0000

description:
Add a new flag, used by vn_open() which prevent symlinks from being followed
at open time. Use this to prevent coredump to follow symlinks when the
kernel opens/creates the file.

diffstat:

 sys/kern/kern_sig.c  |  7 ++++---
 sys/kern/vfs_vnops.c |  9 +++++++--
 sys/sys/fcntl.h      |  9 ++++++++-
 3 files changed, 19 insertions(+), 6 deletions(-)

diffs (74 lines):

diff -r 5b0db9fe5f55 -r 9f8dc4fdd188 sys/kern/kern_sig.c
--- a/sys/kern/kern_sig.c       Tue Aug 31 10:11:52 1999 +0000
+++ b/sys/kern/kern_sig.c       Tue Aug 31 12:30:35 1999 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: kern_sig.c,v 1.92 1999/07/25 06:30:34 thorpej Exp $    */
+/*     $NetBSD: kern_sig.c,v 1.93 1999/08/31 12:30:35 bouyer Exp $     */
 
 /*
  * Copyright (c) 1982, 1986, 1989, 1991, 1993
@@ -1297,8 +1297,9 @@
                sprintf(name, "core");
        else
                sprintf(name, "%s.core", p->p_comm);
-       NDINIT(&nd, LOOKUP, FOLLOW, UIO_SYSSPACE, name, p);
-       error = vn_open(&nd, O_CREAT | FWRITE, S_IRUSR | S_IWUSR);
+       
+       NDINIT(&nd, LOOKUP, NOFOLLOW, UIO_SYSSPACE, name, p);
+       error = vn_open(&nd, O_CREAT | FWRITE | FNOSYMLINK, S_IRUSR | S_IWUSR);
        if (error)
                return (error);
        vp = nd.ni_vp;
diff -r 5b0db9fe5f55 -r 9f8dc4fdd188 sys/kern/vfs_vnops.c
--- a/sys/kern/vfs_vnops.c      Tue Aug 31 10:11:52 1999 +0000
+++ b/sys/kern/vfs_vnops.c      Tue Aug 31 12:30:35 1999 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: vfs_vnops.c,v 1.37 1999/08/03 20:19:17 wrstuden Exp $  */
+/*     $NetBSD: vfs_vnops.c,v 1.38 1999/08/31 12:30:36 bouyer Exp $    */
 
 /*
  * Copyright (c) 1982, 1986, 1989, 1993
@@ -85,7 +85,8 @@
        if (fmode & O_CREAT) {
                ndp->ni_cnd.cn_nameiop = CREATE;
                ndp->ni_cnd.cn_flags = LOCKPARENT | LOCKLEAF;
-               if ((fmode & O_EXCL) == 0)
+               if ((fmode & O_EXCL) == 0 &&
+                   ((fmode & FNOSYMLINK) == 0))
                        ndp->ni_cnd.cn_flags |= FOLLOW;
                if ((error = namei(ndp)) != 0)
                        return (error);
@@ -114,6 +115,10 @@
                                error = EEXIST;
                                goto bad;
                        }
+                       if (ndp->ni_vp->v_type == VLNK) {
+                               error = EFTYPE;
+                               goto bad;
+                       }
                        fmode &= ~O_CREAT;
                }
        } else {
diff -r 5b0db9fe5f55 -r 9f8dc4fdd188 sys/sys/fcntl.h
--- a/sys/sys/fcntl.h   Tue Aug 31 10:11:52 1999 +0000
+++ b/sys/sys/fcntl.h   Tue Aug 31 12:30:35 1999 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: fcntl.h,v 1.16 1999/08/03 20:19:21 wrstuden Exp $      */
+/*     $NetBSD: fcntl.h,v 1.17 1999/08/31 12:30:35 bouyer Exp $        */
 
 /*-
  * Copyright (c) 1983, 1990, 1993
@@ -125,6 +125,13 @@
 #define        FMARK           0x00001000      /* mark during gc() */
 #define        FDEFER          0x00002000      /* defer for next gc pass */
 #define        FHASLOCK        0x00004000      /* descriptor holds advisory lock */
+/*
+ * Note: The below is not a flag that can be used in the struct file. 
+ * It's an option that can be passed to vn_open to make sure it doesn't
+ * follow a symlink on the last lookup
+ */
+#define        FNOSYMLINK      0x00080000      /* Don't follow symlink for last
+                                          component */
 /* bits to save after open(2) */
 #define        FMASK           (FREAD|FWRITE|FAPPEND|FASYNC|FFSYNC|FNONBLOCK|FDSYNC|\
                         FRSYNC|FALTIO)