2005-01-06 23:35:40 +00:00
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/*-
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2017-11-20 19:43:44 +00:00
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* SPDX-License-Identifier: BSD-3-Clause
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*
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1994-05-24 10:09:53 +00:00
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* Copyright (c) 1982, 1986, 1989, 1993
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* The Regents of the University of California. All rights reserved.
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* (c) UNIX System Laboratories, Inc.
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* All or some portions of this file are derived from material licensed
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* to the University of California by American Telephone and Telegraph
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* Co. or Unix System Laboratories, Inc. and are reproduced herein with
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* the permission of UNIX System Laboratories, Inc.
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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2016-09-15 13:16:20 +00:00
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* 3. Neither the name of the University nor the names of its contributors
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1994-05-24 10:09:53 +00:00
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* may be used to endorse or promote products derived from this software
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* without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
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* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
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* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
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* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
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* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
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* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
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* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
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* SUCH DAMAGE.
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*/
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2003-06-11 00:56:59 +00:00
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#include <sys/cdefs.h>
|
2011-08-11 12:30:23 +00:00
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|
|
#include "opt_capsicum.h"
|
1996-01-03 21:42:35 +00:00
|
|
|
#include "opt_ktrace.h"
|
|
|
|
|
1994-05-24 10:09:53 +00:00
|
|
|
#include <sys/param.h>
|
1994-08-18 22:36:09 +00:00
|
|
|
#include <sys/systm.h>
|
2021-03-27 17:42:48 +00:00
|
|
|
#include <sys/dirent.h>
|
2000-12-06 07:09:08 +00:00
|
|
|
#include <sys/kernel.h>
|
2014-03-16 10:55:57 +00:00
|
|
|
#include <sys/capsicum.h>
|
2008-03-31 12:01:21 +00:00
|
|
|
#include <sys/fcntl.h>
|
2009-05-27 14:11:23 +00:00
|
|
|
#include <sys/jail.h>
|
2001-05-01 08:13:21 +00:00
|
|
|
#include <sys/lock.h>
|
2002-01-13 21:37:49 +00:00
|
|
|
#include <sys/mutex.h>
|
1994-05-24 10:09:53 +00:00
|
|
|
#include <sys/namei.h>
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|
|
|
#include <sys/vnode.h>
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|
|
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#include <sys/mount.h>
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|
|
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#include <sys/filedesc.h>
|
|
|
|
#include <sys/proc.h>
|
2009-04-06 10:32:40 +00:00
|
|
|
#include <sys/sdt.h>
|
2005-02-07 18:44:55 +00:00
|
|
|
#include <sys/syscallsubr.h>
|
2005-04-03 23:50:20 +00:00
|
|
|
#include <sys/sysctl.h>
|
1994-05-24 10:09:53 +00:00
|
|
|
#ifdef KTRACE
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|
#include <sys/ktrace.h>
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|
|
#endif
|
2020-08-11 01:34:40 +00:00
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|
#ifdef INVARIANTS
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#include <machine/_inttypes.h>
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#endif
|
1994-05-24 10:09:53 +00:00
|
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|
|
2006-02-05 15:42:01 +00:00
|
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|
#include <security/audit/audit.h>
|
2006-10-22 11:52:19 +00:00
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|
#include <security/mac/mac_framework.h>
|
2006-02-05 15:42:01 +00:00
|
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|
2002-03-20 04:09:59 +00:00
|
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#include <vm/uma.h>
|
1997-12-27 02:56:39 +00:00
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|
2022-09-12 22:49:47 +00:00
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#ifdef INVARIANTS
|
2022-09-17 09:10:38 +00:00
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static void NDVALIDATE_impl(struct nameidata *, int);
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#define NDVALIDATE(ndp) NDVALIDATE_impl(ndp, __LINE__)
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2022-09-17 10:45:12 +00:00
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|
#else
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#define NDVALIDATE(ndp)
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#endif
|
2022-09-17 09:10:38 +00:00
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|
2023-06-13 12:22:09 +00:00
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|
|
/*
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* Prepare namei() to restart. Reset components to its original state and set
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* ISRESTARTED flag which signals the underlying lookup code to change the root
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* from ABI root to actual root and prevents a further restarts.
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|
*/
|
2023-05-29 08:15:28 +00:00
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#define NDRESTART(ndp) do { \
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NDREINIT_DBG(ndp); \
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ndp->ni_resflags = 0; \
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ndp->ni_cnd.cn_flags &= ~NAMEI_INTERNAL_FLAGS; \
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ndp->ni_cnd.cn_flags |= ISRESTARTED; \
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} while (0)
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|
2024-04-24 19:06:14 +00:00
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|
#ifdef KTRACE
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#define NIKTRCAPFAIL(path) ktrcapfail(CAPFAIL_NAMEI, (path))
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#else
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#define NIKTRCAPFAIL(path)
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#endif
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|
2024-04-24 18:55:37 +00:00
|
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#define NI_CAP_VIOLATION(ndp, path) do { \
|
2024-04-24 19:06:14 +00:00
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NIKTRCAPFAIL(path); \
|
2024-04-24 18:55:37 +00:00
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|
(ndp)->ni_lcf &= ~NI_LCF_KTR_FLAGS; \
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} while (0)
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|
|
2020-08-10 18:11:00 +00:00
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|
|
SDT_PROVIDER_DEFINE(vfs);
|
2020-07-25 10:37:15 +00:00
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|
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SDT_PROBE_DEFINE4(vfs, namei, lookup, entry, "struct vnode *", "char *",
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"unsigned long", "bool");
|
2021-01-12 13:09:55 +00:00
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SDT_PROBE_DEFINE4(vfs, namei, lookup, return, "int", "struct vnode *", "bool",
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|
|
"struct nameidata");
|
2009-04-06 10:32:40 +00:00
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|
2016-11-02 12:02:31 +00:00
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|
|
/* Allocation zone for namei. */
|
2002-03-20 04:09:59 +00:00
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|
uma_zone_t namei_zone;
|
2016-11-02 12:02:31 +00:00
|
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|
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|
/* Placeholder vnode for mp traversal. */
|
Below is slightly edited description of the LOR by Tor Egge:
--------------------------
[Deadlock] is caused by a lock order reversal in vfs_lookup(), where
[some] process is trying to lock a directory vnode, that is the parent
directory of covered vnode) while holding an exclusive vnode lock on
covering vnode.
A simplified scenario:
root fs var fs
/ A / (/var) D
/var B /log (/var/log) E
vfs lock C vfs lock F
Within each file system, the lock order is clear: C->A->B and F->D->E
When traversing across mounts, the system can choose between two lock orders,
but everything must then follow that lock order:
L1: C->A->B
|
+->F->D->E
L2: F->D->E
|
+->C->A->B
The lookup() process for namei("/var") mixes those two lock orders:
VOP_LOOKUP() obtains B while A is held
vfs_busy() obtains a shared lock on F while A and B are held (follows L1,
violates L2)
vput() releases lock on B
VOP_UNLOCK() releases lock on A
VFS_ROOT() obtains lock on D while shared lock on F is held
vfs_unbusy() releases shared lock on F
vn_lock() obtains lock on A while D is held (violates L1, follows L2)
dounmount() follows L1 (B is locked while F is drained).
Without unmount activity, vfs_busy() will always succeed without blocking
and the deadlock isn't triggered (the system behaves as if L2 is followed).
With unmount, you can get 4 processes in a deadlock:
p1: holds D, want A (in lookup())
p2: holds shared lock on F, want D (in VFS_ROOT())
p3: holds B, want drain lock on F (in dounmount())
p4: holds A, want B (in VOP_LOOKUP())
You can have more than one instance of p2.
The reversal was introduced in revision 1.81 of src/sys/kern/vfs_lookup.c and
MFCed to revision 1.80.2.1, probably to avoid a cascade of vnode locks when nfs
servers are dead (VFS_ROOT() just hangs) spreading to the root fs root vnode.
- Tor Egge
To fix the LOR, ups@ noted that when crossing the mount point, ni_dvp
is actually not used by the callers of namei. Thus, placeholder deadfs
vnode vp_crossmp is introduced that is filled into ni_dvp.
Idea by: ups
Reviewed by: tegge, ups, jeff, rwatson (mac interaction)
Tested by: Peter Holm
MFC after: 2 weeks
2007-01-22 11:25:22 +00:00
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static struct vnode *vp_crossmp;
|
2000-12-06 07:09:08 +00:00
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|
2016-12-02 18:03:15 +00:00
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static int
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crossmp_vop_islocked(struct vop_islocked_args *ap)
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{
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return (LK_SHARED);
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}
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static int
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crossmp_vop_lock1(struct vop_lock1_args *ap)
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{
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struct vnode *vp;
|
2021-08-23 10:10:38 +00:00
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struct lock *lk __diagused;
|
2022-08-05 05:39:04 +00:00
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int flags;
|
2016-12-02 18:03:15 +00:00
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vp = ap->a_vp;
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lk = vp->v_vnlock;
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flags = ap->a_flags;
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|
2022-08-05 05:39:04 +00:00
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KASSERT((flags & (LK_SHARED | LK_NOWAIT)) == (LK_SHARED | LK_NOWAIT),
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("%s: invalid lock request 0x%x for crossmp", __func__, flags));
|
2016-12-02 18:03:15 +00:00
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if ((flags & LK_INTERLOCK) != 0)
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VI_UNLOCK(vp);
|
2022-04-27 18:46:16 +00:00
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LOCK_LOG_LOCK("SLOCK", &lk->lock_object, 0, 0, ap->a_file, ap->a_line);
|
2016-12-02 18:03:15 +00:00
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|
return (0);
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|
}
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static int
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crossmp_vop_unlock(struct vop_unlock_args *ap)
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|
{
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|
struct vnode *vp;
|
2021-08-23 10:10:38 +00:00
|
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|
struct lock *lk __diagused;
|
2016-12-02 18:03:15 +00:00
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vp = ap->a_vp;
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lk = vp->v_vnlock;
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LOCK_LOG_LOCK("SUNLOCK", &lk->lock_object, 0, 0, LOCK_FILE,
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LOCK_LINE);
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|
return (0);
|
|
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|
}
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|
static struct vop_vector crossmp_vnodeops = {
|
2017-01-22 19:36:02 +00:00
|
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|
.vop_default = &default_vnodeops,
|
2016-12-02 18:03:15 +00:00
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.vop_islocked = crossmp_vop_islocked,
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.vop_lock1 = crossmp_vop_lock1,
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.vop_unlock = crossmp_vop_unlock,
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};
|
2019-12-16 00:06:22 +00:00
|
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/*
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* VFS_VOP_VECTOR_REGISTER(crossmp_vnodeops) is not used here since the vnode
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* gets allocated early. See nameiinit for the direct call below.
|
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*/
|
2016-12-02 18:03:15 +00:00
|
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|
2016-11-02 12:43:15 +00:00
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struct nameicap_tracker {
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struct vnode *dp;
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TAILQ_ENTRY(nameicap_tracker) nm_link;
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};
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/* Zone for cap mode tracker elements used for dotdot capability checks. */
|
2020-11-05 12:06:50 +00:00
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MALLOC_DEFINE(M_NAMEITRACKER, "namei_tracker", "namei tracking for dotdot");
|
2016-11-02 12:43:15 +00:00
|
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|
2000-12-06 07:09:08 +00:00
|
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static void
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nameiinit(void *dummy __unused)
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{
|
2007-03-31 16:08:50 +00:00
|
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|
|
2002-03-19 09:11:49 +00:00
|
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|
namei_zone = uma_zcreate("NAMEI", MAXPATHLEN, NULL, NULL, NULL, NULL,
|
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|
|
UMA_ALIGN_PTR, 0);
|
2019-12-16 00:06:22 +00:00
|
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|
vfs_vector_op_register(&crossmp_vnodeops);
|
2016-12-02 18:03:15 +00:00
|
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getnewvnode("crossmp", NULL, &crossmp_vnodeops, &vp_crossmp);
|
2022-12-19 13:00:30 +00:00
|
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vp_crossmp->v_state = VSTATE_CONSTRUCTED;
|
2023-04-08 06:15:00 +00:00
|
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|
vp_crossmp->v_irflag |= VIRF_CROSSMP;
|
2000-12-06 07:09:08 +00:00
|
|
|
}
|
2008-03-16 10:58:09 +00:00
|
|
|
SYSINIT(vfs, SI_SUB_VFS, SI_ORDER_SECOND, nameiinit, NULL);
|
2000-12-06 07:09:08 +00:00
|
|
|
|
2016-12-12 11:12:04 +00:00
|
|
|
static int lookup_cap_dotdot = 1;
|
2016-11-02 12:43:15 +00:00
|
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SYSCTL_INT(_vfs, OID_AUTO, lookup_cap_dotdot, CTLFLAG_RWTUN,
|
|
|
|
&lookup_cap_dotdot, 0,
|
|
|
|
"enables \"..\" components in path lookup in capability mode");
|
2016-12-12 11:12:04 +00:00
|
|
|
static int lookup_cap_dotdot_nonlocal = 1;
|
2016-11-02 12:43:15 +00:00
|
|
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SYSCTL_INT(_vfs, OID_AUTO, lookup_cap_dotdot_nonlocal, CTLFLAG_RWTUN,
|
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|
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&lookup_cap_dotdot_nonlocal, 0,
|
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"enables \"..\" components in path lookup in capability mode "
|
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|
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"on non-local mount");
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static void
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|
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nameicap_tracker_add(struct nameidata *ndp, struct vnode *dp)
|
|
|
|
{
|
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struct nameicap_tracker *nt;
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|
|
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|
if ((ndp->ni_lcf & NI_LCF_CAP_DOTDOT) == 0 || dp->v_type != VDIR)
|
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|
|
return;
|
2021-02-28 00:13:19 +00:00
|
|
|
nt = TAILQ_LAST(&ndp->ni_cap_tracker, nameicap_tracker_head);
|
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|
|
if (nt != NULL && nt->dp == dp)
|
|
|
|
return;
|
2020-11-05 12:06:50 +00:00
|
|
|
nt = malloc(sizeof(*nt), M_NAMEITRACKER, M_WAITOK);
|
2016-11-02 12:43:15 +00:00
|
|
|
vhold(dp);
|
|
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|
nt->dp = dp;
|
|
|
|
TAILQ_INSERT_TAIL(&ndp->ni_cap_tracker, nt, nm_link);
|
|
|
|
}
|
|
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|
|
static void
|
2021-02-28 00:14:43 +00:00
|
|
|
nameicap_cleanup_from(struct nameidata *ndp, struct nameicap_tracker *first)
|
2016-11-02 12:43:15 +00:00
|
|
|
{
|
|
|
|
struct nameicap_tracker *nt, *nt1;
|
|
|
|
|
2021-02-28 00:14:43 +00:00
|
|
|
nt = first;
|
|
|
|
TAILQ_FOREACH_FROM_SAFE(nt, &ndp->ni_cap_tracker, nm_link, nt1) {
|
2016-11-02 12:43:15 +00:00
|
|
|
TAILQ_REMOVE(&ndp->ni_cap_tracker, nt, nm_link);
|
|
|
|
vdrop(nt->dp);
|
2020-11-05 12:06:50 +00:00
|
|
|
free(nt, M_NAMEITRACKER);
|
2016-11-02 12:43:15 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2021-02-28 00:14:43 +00:00
|
|
|
static void
|
|
|
|
nameicap_cleanup(struct nameidata *ndp)
|
|
|
|
{
|
|
|
|
KASSERT(TAILQ_EMPTY(&ndp->ni_cap_tracker) ||
|
|
|
|
(ndp->ni_lcf & NI_LCF_CAP_DOTDOT) != 0, ("not strictrelative"));
|
|
|
|
nameicap_cleanup_from(ndp, NULL);
|
|
|
|
}
|
|
|
|
|
2016-11-02 12:43:15 +00:00
|
|
|
/*
|
|
|
|
* For dotdot lookups in capability mode, only allow the component
|
|
|
|
* lookup to succeed if the resulting directory was already traversed
|
2020-09-22 21:54:30 +00:00
|
|
|
* during the operation. This catches situations where already
|
|
|
|
* traversed directory is moved to different parent, and then we walk
|
|
|
|
* over it with dotdots.
|
|
|
|
*
|
|
|
|
* Also allow to force failure of dotdot lookups for non-local
|
2016-11-02 12:43:15 +00:00
|
|
|
* filesystems, where external agents might assist local lookups to
|
|
|
|
* escape the compartment.
|
|
|
|
*/
|
|
|
|
static int
|
|
|
|
nameicap_check_dotdot(struct nameidata *ndp, struct vnode *dp)
|
|
|
|
{
|
|
|
|
struct nameicap_tracker *nt;
|
|
|
|
struct mount *mp;
|
|
|
|
|
2021-02-16 03:31:40 +00:00
|
|
|
if (dp == NULL || dp->v_type != VDIR || (ndp->ni_lcf &
|
2024-04-06 18:31:25 +00:00
|
|
|
NI_LCF_STRICTREL) == 0)
|
2016-11-02 12:43:15 +00:00
|
|
|
return (0);
|
2024-04-06 18:31:25 +00:00
|
|
|
if (__predict_false((ndp->ni_lcf & (NI_LCF_STRICTREL_KTR |
|
|
|
|
NI_LCF_CAP_DOTDOT_KTR)) == NI_LCF_STRICTREL_KTR))
|
|
|
|
NI_CAP_VIOLATION(ndp, ndp->ni_cnd.cn_pnbuf);
|
2021-02-16 03:31:40 +00:00
|
|
|
if ((ndp->ni_lcf & NI_LCF_CAP_DOTDOT) == 0)
|
|
|
|
return (ENOTCAPABLE);
|
2016-11-02 12:43:15 +00:00
|
|
|
mp = dp->v_mount;
|
|
|
|
if (lookup_cap_dotdot_nonlocal == 0 && mp != NULL &&
|
|
|
|
(mp->mnt_flag & MNT_LOCAL) == 0)
|
2024-04-06 18:31:25 +00:00
|
|
|
goto capfail;
|
2016-11-02 12:43:15 +00:00
|
|
|
TAILQ_FOREACH_REVERSE(nt, &ndp->ni_cap_tracker, nameicap_tracker_head,
|
|
|
|
nm_link) {
|
2021-02-28 00:15:21 +00:00
|
|
|
if (dp == nt->dp) {
|
|
|
|
nt = TAILQ_NEXT(nt, nm_link);
|
|
|
|
if (nt != NULL)
|
|
|
|
nameicap_cleanup_from(ndp, nt);
|
2016-11-02 12:43:15 +00:00
|
|
|
return (0);
|
2021-02-28 00:15:21 +00:00
|
|
|
}
|
2016-11-02 12:43:15 +00:00
|
|
|
}
|
2024-04-06 18:31:25 +00:00
|
|
|
|
|
|
|
capfail:
|
|
|
|
if (__predict_false((ndp->ni_lcf & NI_LCF_STRICTREL_KTR) != 0))
|
|
|
|
NI_CAP_VIOLATION(ndp, ndp->ni_cnd.cn_pnbuf);
|
2016-11-02 12:43:15 +00:00
|
|
|
return (ENOTCAPABLE);
|
|
|
|
}
|
|
|
|
|
2015-07-05 22:56:41 +00:00
|
|
|
static void
|
|
|
|
namei_cleanup_cnp(struct componentname *cnp)
|
|
|
|
{
|
2016-11-02 12:02:31 +00:00
|
|
|
|
2015-07-05 22:56:41 +00:00
|
|
|
uma_zfree(namei_zone, cnp->cn_pnbuf);
|
|
|
|
cnp->cn_pnbuf = NULL;
|
|
|
|
cnp->cn_nameptr = NULL;
|
|
|
|
}
|
|
|
|
|
2015-07-09 15:06:58 +00:00
|
|
|
static int
|
2020-03-01 21:54:28 +00:00
|
|
|
namei_handle_root(struct nameidata *ndp, struct vnode **dpp)
|
2015-07-09 15:06:58 +00:00
|
|
|
{
|
2015-07-09 17:17:26 +00:00
|
|
|
struct componentname *cnp;
|
2015-07-09 15:06:58 +00:00
|
|
|
|
2015-07-09 17:17:26 +00:00
|
|
|
cnp = &ndp->ni_cnd;
|
2024-04-06 18:31:25 +00:00
|
|
|
if (__predict_false((ndp->ni_lcf & (NI_LCF_STRICTREL |
|
|
|
|
NI_LCF_STRICTREL_KTR)) != 0)) {
|
|
|
|
if ((ndp->ni_lcf & NI_LCF_STRICTREL_KTR) != 0)
|
|
|
|
NI_CAP_VIOLATION(ndp, cnp->cn_pnbuf);
|
|
|
|
if ((ndp->ni_lcf & NI_LCF_STRICTREL) != 0)
|
|
|
|
return (ENOTCAPABLE);
|
2015-07-09 15:06:58 +00:00
|
|
|
}
|
|
|
|
while (*(cnp->cn_nameptr) == '/') {
|
|
|
|
cnp->cn_nameptr++;
|
|
|
|
ndp->ni_pathlen--;
|
|
|
|
}
|
|
|
|
*dpp = ndp->ni_rootdir;
|
2020-03-01 21:54:28 +00:00
|
|
|
vrefact(*dpp);
|
2015-07-09 15:06:58 +00:00
|
|
|
return (0);
|
|
|
|
}
|
|
|
|
|
2020-07-25 10:37:15 +00:00
|
|
|
static int
|
|
|
|
namei_setup(struct nameidata *ndp, struct vnode **dpp, struct pwd **pwdp)
|
1994-05-24 10:09:53 +00:00
|
|
|
{
|
2016-11-02 12:02:31 +00:00
|
|
|
struct componentname *cnp;
|
|
|
|
struct thread *td;
|
2020-03-01 21:53:46 +00:00
|
|
|
struct pwd *pwd;
|
2020-07-30 07:11:08 +00:00
|
|
|
int error;
|
|
|
|
bool startdir_used;
|
2004-08-04 18:39:07 +00:00
|
|
|
|
2016-11-02 12:02:31 +00:00
|
|
|
cnp = &ndp->ni_cnd;
|
2021-10-01 21:16:54 +00:00
|
|
|
td = curthread;
|
1996-12-01 16:05:44 +00:00
|
|
|
|
2020-07-30 07:11:08 +00:00
|
|
|
startdir_used = false;
|
2020-07-25 10:37:15 +00:00
|
|
|
*pwdp = NULL;
|
2020-08-05 07:33:39 +00:00
|
|
|
*dpp = NULL;
|
1996-12-01 16:05:44 +00:00
|
|
|
|
2011-08-13 09:21:16 +00:00
|
|
|
#ifdef CAPABILITY_MODE
|
|
|
|
/*
|
2016-11-02 12:43:15 +00:00
|
|
|
* In capability mode, lookups must be restricted to happen in
|
|
|
|
* the subtree with the root specified by the file descriptor:
|
|
|
|
* - The root must be real file descriptor, not the pseudo-descriptor
|
|
|
|
* AT_FDCWD.
|
|
|
|
* - The passed path must be relative and not absolute.
|
|
|
|
* - If lookup_cap_dotdot is disabled, path must not contain the
|
|
|
|
* '..' components.
|
|
|
|
* - If lookup_cap_dotdot is enabled, we verify that all '..'
|
|
|
|
* components lookups result in the directories which were
|
|
|
|
* previously walked by us, which prevents an escape from
|
|
|
|
* the relative root.
|
2011-08-13 09:21:16 +00:00
|
|
|
*/
|
2024-04-06 18:31:25 +00:00
|
|
|
if ((cnp->cn_flags & NOCAPCHECK) == 0) {
|
|
|
|
if (CAP_TRACING(td)) {
|
|
|
|
ndp->ni_lcf |= NI_LCF_STRICTREL_KTR;
|
|
|
|
if (ndp->ni_dirfd == AT_FDCWD)
|
|
|
|
NI_CAP_VIOLATION(ndp, "AT_FDCWD");
|
|
|
|
}
|
|
|
|
if (IN_CAPABILITY_MODE(td)) {
|
|
|
|
ndp->ni_lcf |= NI_LCF_STRICTREL;
|
|
|
|
ndp->ni_resflags |= NIRES_STRICTREL;
|
|
|
|
if (ndp->ni_dirfd == AT_FDCWD)
|
|
|
|
return (ECAPMODE);
|
2011-10-18 07:28:58 +00:00
|
|
|
}
|
2011-08-13 09:21:16 +00:00
|
|
|
}
|
|
|
|
#endif
|
2020-07-25 10:37:15 +00:00
|
|
|
error = 0;
|
|
|
|
|
1994-05-24 10:09:53 +00:00
|
|
|
/*
|
|
|
|
* Get starting point for the translation.
|
|
|
|
*/
|
2020-03-01 21:53:46 +00:00
|
|
|
pwd = pwd_hold(td);
|
2020-02-01 06:40:35 +00:00
|
|
|
/*
|
|
|
|
* The reference on ni_rootdir is acquired in the block below to avoid
|
|
|
|
* back-to-back atomics for absolute lookups.
|
|
|
|
*/
|
2023-05-29 08:15:28 +00:00
|
|
|
namei_setup_rootdir(ndp, cnp, pwd);
|
2020-03-01 21:53:46 +00:00
|
|
|
ndp->ni_topdir = pwd->pwd_jdir;
|
1998-02-15 04:17:09 +00:00
|
|
|
|
2015-07-09 15:06:58 +00:00
|
|
|
if (cnp->cn_pnbuf[0] == '/') {
|
2019-02-08 04:18:17 +00:00
|
|
|
ndp->ni_resflags |= NIRES_ABS;
|
2020-07-25 10:37:15 +00:00
|
|
|
error = namei_handle_root(ndp, dpp);
|
2015-07-09 15:06:58 +00:00
|
|
|
} else {
|
Update ZFS from version 6 to 13 and bring some FreeBSD-specific changes.
This bring huge amount of changes, I'll enumerate only user-visible changes:
- Delegated Administration
Allows regular users to perform ZFS operations, like file system
creation, snapshot creation, etc.
- L2ARC
Level 2 cache for ZFS - allows to use additional disks for cache.
Huge performance improvements mostly for random read of mostly
static content.
- slog
Allow to use additional disks for ZFS Intent Log to speed up
operations like fsync(2).
- vfs.zfs.super_owner
Allows regular users to perform privileged operations on files stored
on ZFS file systems owned by him. Very careful with this one.
- chflags(2)
Not all the flags are supported. This still needs work.
- ZFSBoot
Support to boot off of ZFS pool. Not finished, AFAIK.
Submitted by: dfr
- Snapshot properties
- New failure modes
Before if write requested failed, system paniced. Now one
can select from one of three failure modes:
- panic - panic on write error
- wait - wait for disk to reappear
- continue - serve read requests if possible, block write requests
- Refquota, refreservation properties
Just quota and reservation properties, but don't count space consumed
by children file systems, clones and snapshots.
- Sparse volumes
ZVOLs that don't reserve space in the pool.
- External attributes
Compatible with extattr(2).
- NFSv4-ACLs
Not sure about the status, might not be complete yet.
Submitted by: trasz
- Creation-time properties
- Regression tests for zpool(8) command.
Obtained from: OpenSolaris
2008-11-17 20:49:29 +00:00
|
|
|
if (ndp->ni_startdir != NULL) {
|
2020-07-25 10:37:15 +00:00
|
|
|
*dpp = ndp->ni_startdir;
|
2020-07-30 07:11:08 +00:00
|
|
|
startdir_used = true;
|
2015-07-09 16:32:58 +00:00
|
|
|
} else if (ndp->ni_dirfd == AT_FDCWD) {
|
2020-07-25 10:37:15 +00:00
|
|
|
*dpp = pwd->pwd_cdir;
|
|
|
|
vrefact(*dpp);
|
2015-07-09 16:32:58 +00:00
|
|
|
} else {
|
2009-07-28 21:39:58 +00:00
|
|
|
if (cnp->cn_flags & AUDITVNODE1)
|
|
|
|
AUDIT_ARG_ATFD1(ndp->ni_dirfd);
|
|
|
|
if (cnp->cn_flags & AUDITVNODE2)
|
|
|
|
AUDIT_ARG_ATFD2(ndp->ni_dirfd);
|
2022-03-24 20:51:03 +00:00
|
|
|
|
2024-01-04 13:11:54 +00:00
|
|
|
error = fgetvp_lookup(ndp, dpp);
|
2009-07-28 21:39:58 +00:00
|
|
|
}
|
2021-03-07 14:29:09 +00:00
|
|
|
if (error == 0 && (*dpp)->v_type != VDIR &&
|
|
|
|
(cnp->cn_pnbuf[0] != '\0' ||
|
|
|
|
(cnp->cn_flags & EMPTYPATH) == 0))
|
2015-07-09 16:32:58 +00:00
|
|
|
error = ENOTDIR;
|
Update ZFS from version 6 to 13 and bring some FreeBSD-specific changes.
This bring huge amount of changes, I'll enumerate only user-visible changes:
- Delegated Administration
Allows regular users to perform ZFS operations, like file system
creation, snapshot creation, etc.
- L2ARC
Level 2 cache for ZFS - allows to use additional disks for cache.
Huge performance improvements mostly for random read of mostly
static content.
- slog
Allow to use additional disks for ZFS Intent Log to speed up
operations like fsync(2).
- vfs.zfs.super_owner
Allows regular users to perform privileged operations on files stored
on ZFS file systems owned by him. Very careful with this one.
- chflags(2)
Not all the flags are supported. This still needs work.
- ZFSBoot
Support to boot off of ZFS pool. Not finished, AFAIK.
Submitted by: dfr
- Snapshot properties
- New failure modes
Before if write requested failed, system paniced. Now one
can select from one of three failure modes:
- panic - panic on write error
- wait - wait for disk to reappear
- continue - serve read requests if possible, block write requests
- Refquota, refreservation properties
Just quota and reservation properties, but don't count space consumed
by children file systems, clones and snapshots.
- Sparse volumes
ZVOLs that don't reserve space in the pool.
- External attributes
Compatible with extattr(2).
- NFSv4-ACLs
Not sure about the status, might not be complete yet.
Submitted by: trasz
- Creation-time properties
- Regression tests for zpool(8) command.
Obtained from: OpenSolaris
2008-11-17 20:49:29 +00:00
|
|
|
}
|
2020-09-22 22:48:12 +00:00
|
|
|
if (error == 0 && (cnp->cn_flags & RBENEATH) != 0) {
|
2021-02-16 03:31:40 +00:00
|
|
|
if (cnp->cn_pnbuf[0] == '/') {
|
2021-02-28 23:59:12 +00:00
|
|
|
error = ENOTCAPABLE;
|
2024-04-06 18:31:25 +00:00
|
|
|
} else if ((ndp->ni_lcf & NI_LCF_STRICTREL) == 0) {
|
|
|
|
ndp->ni_lcf |= NI_LCF_STRICTREL |
|
2020-09-22 22:48:12 +00:00
|
|
|
NI_LCF_CAP_DOTDOT;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2020-02-21 01:44:31 +00:00
|
|
|
/*
|
|
|
|
* If we are auditing the kernel pathname, save the user pathname.
|
|
|
|
*/
|
2023-05-03 06:56:10 +00:00
|
|
|
if (AUDITING_TD(td)) {
|
|
|
|
if (cnp->cn_flags & AUDITVNODE1)
|
|
|
|
AUDIT_ARG_UPATH1_VP(td, ndp->ni_rootdir, *dpp, cnp->cn_pnbuf);
|
|
|
|
if (cnp->cn_flags & AUDITVNODE2)
|
|
|
|
AUDIT_ARG_UPATH2_VP(td, ndp->ni_rootdir, *dpp, cnp->cn_pnbuf);
|
|
|
|
}
|
2015-07-09 16:32:58 +00:00
|
|
|
if (ndp->ni_startdir != NULL && !startdir_used)
|
|
|
|
vrele(ndp->ni_startdir);
|
|
|
|
if (error != 0) {
|
2020-07-25 10:37:15 +00:00
|
|
|
if (*dpp != NULL)
|
|
|
|
vrele(*dpp);
|
2020-08-13 10:24:45 +00:00
|
|
|
pwd_drop(pwd);
|
2020-07-25 10:37:15 +00:00
|
|
|
return (error);
|
2008-03-31 12:01:21 +00:00
|
|
|
}
|
2024-04-06 18:31:25 +00:00
|
|
|
if (lookup_cap_dotdot != 0) {
|
|
|
|
if ((ndp->ni_lcf & NI_LCF_STRICTREL_KTR) != 0)
|
|
|
|
ndp->ni_lcf |= NI_LCF_CAP_DOTDOT_KTR;
|
|
|
|
if ((ndp->ni_lcf & NI_LCF_STRICTREL) != 0)
|
|
|
|
ndp->ni_lcf |= NI_LCF_CAP_DOTDOT;
|
|
|
|
}
|
2020-07-25 10:37:15 +00:00
|
|
|
SDT_PROBE4(vfs, namei, lookup, entry, *dpp, cnp->cn_pnbuf,
|
|
|
|
cnp->cn_flags, false);
|
|
|
|
*pwdp = pwd;
|
|
|
|
return (0);
|
|
|
|
}
|
|
|
|
|
2020-12-06 04:59:24 +00:00
|
|
|
static int
|
|
|
|
namei_getpath(struct nameidata *ndp)
|
|
|
|
{
|
|
|
|
struct componentname *cnp;
|
|
|
|
int error;
|
|
|
|
|
|
|
|
cnp = &ndp->ni_cnd;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Get a buffer for the name to be translated, and copy the
|
|
|
|
* name into the buffer.
|
|
|
|
*/
|
|
|
|
cnp->cn_pnbuf = uma_zalloc(namei_zone, M_WAITOK);
|
|
|
|
if (ndp->ni_segflg == UIO_SYSSPACE) {
|
|
|
|
error = copystr(ndp->ni_dirp, cnp->cn_pnbuf, MAXPATHLEN,
|
|
|
|
&ndp->ni_pathlen);
|
|
|
|
} else {
|
|
|
|
error = copyinstr(ndp->ni_dirp, cnp->cn_pnbuf, MAXPATHLEN,
|
|
|
|
&ndp->ni_pathlen);
|
|
|
|
}
|
|
|
|
|
2022-09-17 00:59:32 +00:00
|
|
|
return (error);
|
2020-12-06 04:59:24 +00:00
|
|
|
}
|
|
|
|
|
2021-03-07 14:29:09 +00:00
|
|
|
static int
|
|
|
|
namei_emptypath(struct nameidata *ndp)
|
|
|
|
{
|
|
|
|
struct componentname *cnp;
|
|
|
|
struct pwd *pwd;
|
|
|
|
struct vnode *dp;
|
|
|
|
int error;
|
|
|
|
|
|
|
|
cnp = &ndp->ni_cnd;
|
|
|
|
MPASS(*cnp->cn_pnbuf == '\0');
|
|
|
|
MPASS((cnp->cn_flags & EMPTYPATH) != 0);
|
|
|
|
MPASS((cnp->cn_flags & (LOCKPARENT | WANTPARENT)) == 0);
|
|
|
|
|
2021-08-13 17:40:10 +00:00
|
|
|
ndp->ni_resflags |= NIRES_EMPTYPATH;
|
2021-03-07 14:29:09 +00:00
|
|
|
error = namei_setup(ndp, &dp, &pwd);
|
|
|
|
if (error != 0) {
|
|
|
|
goto errout;
|
|
|
|
}
|
|
|
|
|
2021-05-13 09:23:03 +00:00
|
|
|
/*
|
|
|
|
* Usecount on dp already provided by namei_setup.
|
|
|
|
*/
|
2021-03-07 14:29:09 +00:00
|
|
|
ndp->ni_vp = dp;
|
|
|
|
pwd_drop(pwd);
|
|
|
|
NDVALIDATE(ndp);
|
|
|
|
if ((cnp->cn_flags & LOCKLEAF) != 0) {
|
|
|
|
VOP_LOCK(dp, (cnp->cn_flags & LOCKSHARED) != 0 ?
|
|
|
|
LK_SHARED : LK_EXCLUSIVE);
|
|
|
|
if (VN_IS_DOOMED(dp)) {
|
|
|
|
vput(dp);
|
|
|
|
error = ENOENT;
|
|
|
|
goto errout;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
SDT_PROBE4(vfs, namei, lookup, return, 0, ndp->ni_vp, false, ndp);
|
|
|
|
return (0);
|
|
|
|
|
|
|
|
errout:
|
|
|
|
SDT_PROBE4(vfs, namei, lookup, return, error, NULL, false, ndp);
|
2022-09-17 09:10:38 +00:00
|
|
|
namei_cleanup_cnp(cnp);
|
2021-03-07 14:29:09 +00:00
|
|
|
return (error);
|
|
|
|
}
|
|
|
|
|
2022-03-24 12:57:30 +00:00
|
|
|
static int __noinline
|
|
|
|
namei_follow_link(struct nameidata *ndp)
|
|
|
|
{
|
|
|
|
char *cp;
|
|
|
|
struct iovec aiov;
|
|
|
|
struct uio auio;
|
|
|
|
struct componentname *cnp;
|
|
|
|
struct thread *td;
|
|
|
|
int error, linklen;
|
|
|
|
|
|
|
|
error = 0;
|
|
|
|
cnp = &ndp->ni_cnd;
|
|
|
|
td = curthread;
|
|
|
|
|
|
|
|
if (ndp->ni_loopcnt++ >= MAXSYMLINKS) {
|
|
|
|
error = ELOOP;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
#ifdef MAC
|
|
|
|
if ((cnp->cn_flags & NOMACCHECK) == 0) {
|
|
|
|
error = mac_vnode_check_readlink(td->td_ucred, ndp->ni_vp);
|
|
|
|
if (error != 0)
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
if (ndp->ni_pathlen > 1)
|
|
|
|
cp = uma_zalloc(namei_zone, M_WAITOK);
|
|
|
|
else
|
|
|
|
cp = cnp->cn_pnbuf;
|
|
|
|
aiov.iov_base = cp;
|
|
|
|
aiov.iov_len = MAXPATHLEN;
|
|
|
|
auio.uio_iov = &aiov;
|
|
|
|
auio.uio_iovcnt = 1;
|
|
|
|
auio.uio_offset = 0;
|
|
|
|
auio.uio_rw = UIO_READ;
|
|
|
|
auio.uio_segflg = UIO_SYSSPACE;
|
|
|
|
auio.uio_td = td;
|
|
|
|
auio.uio_resid = MAXPATHLEN;
|
|
|
|
error = VOP_READLINK(ndp->ni_vp, &auio, cnp->cn_cred);
|
|
|
|
if (error != 0) {
|
|
|
|
if (ndp->ni_pathlen > 1)
|
|
|
|
uma_zfree(namei_zone, cp);
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
linklen = MAXPATHLEN - auio.uio_resid;
|
|
|
|
if (linklen == 0) {
|
|
|
|
if (ndp->ni_pathlen > 1)
|
|
|
|
uma_zfree(namei_zone, cp);
|
|
|
|
error = ENOENT;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
if (linklen + ndp->ni_pathlen > MAXPATHLEN) {
|
|
|
|
if (ndp->ni_pathlen > 1)
|
|
|
|
uma_zfree(namei_zone, cp);
|
|
|
|
error = ENAMETOOLONG;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
if (ndp->ni_pathlen > 1) {
|
|
|
|
bcopy(ndp->ni_next, cp + linklen, ndp->ni_pathlen);
|
|
|
|
uma_zfree(namei_zone, cnp->cn_pnbuf);
|
|
|
|
cnp->cn_pnbuf = cp;
|
|
|
|
} else
|
|
|
|
cnp->cn_pnbuf[linklen] = '\0';
|
|
|
|
ndp->ni_pathlen += linklen;
|
|
|
|
out:
|
|
|
|
return (error);
|
|
|
|
}
|
|
|
|
|
2020-07-25 10:37:15 +00:00
|
|
|
/*
|
|
|
|
* Convert a pathname into a pointer to a locked vnode.
|
|
|
|
*
|
|
|
|
* The FOLLOW flag is set when symbolic links are to be followed
|
|
|
|
* when they occur at the end of the name translation process.
|
|
|
|
* Symbolic links are always followed for all other pathname
|
|
|
|
* components other than the last.
|
|
|
|
*
|
|
|
|
* The segflg defines whether the name is to be copied from user
|
|
|
|
* space or kernel space.
|
|
|
|
*
|
|
|
|
* Overall outline of namei:
|
|
|
|
*
|
|
|
|
* copy in name
|
|
|
|
* get starting directory
|
|
|
|
* while (!done && !error) {
|
|
|
|
* call lookup to search path.
|
|
|
|
* if symbolic link, massage name in buffer and continue
|
|
|
|
* }
|
|
|
|
*/
|
|
|
|
int
|
|
|
|
namei(struct nameidata *ndp)
|
|
|
|
{
|
|
|
|
struct vnode *dp; /* the directory we are searching */
|
|
|
|
struct componentname *cnp;
|
|
|
|
struct thread *td;
|
|
|
|
struct pwd *pwd;
|
2022-03-24 12:57:30 +00:00
|
|
|
int error;
|
2020-07-25 10:37:15 +00:00
|
|
|
enum cache_fpl_status status;
|
|
|
|
|
|
|
|
cnp = &ndp->ni_cnd;
|
2021-10-01 21:16:54 +00:00
|
|
|
td = curthread;
|
2020-08-23 21:06:41 +00:00
|
|
|
#ifdef INVARIANTS
|
2020-10-29 12:56:02 +00:00
|
|
|
KASSERT((ndp->ni_debugflags & NAMEI_DBG_CALLED) == 0,
|
|
|
|
("%s: repeated call to namei without NDREINIT", __func__));
|
|
|
|
KASSERT(ndp->ni_debugflags == NAMEI_DBG_INITED,
|
|
|
|
("%s: bad debugflags %d", __func__, ndp->ni_debugflags));
|
|
|
|
ndp->ni_debugflags |= NAMEI_DBG_CALLED;
|
2020-10-29 18:43:37 +00:00
|
|
|
if (ndp->ni_startdir != NULL)
|
|
|
|
ndp->ni_debugflags |= NAMEI_DBG_HADSTARTDIR;
|
2020-12-27 23:33:04 +00:00
|
|
|
if (cnp->cn_flags & FAILIFEXISTS) {
|
|
|
|
KASSERT(cnp->cn_nameiop == CREATE,
|
|
|
|
("%s: FAILIFEXISTS passed for op %d", __func__, cnp->cn_nameiop));
|
|
|
|
/*
|
|
|
|
* The limitation below is to restrict hairy corner cases.
|
|
|
|
*/
|
|
|
|
KASSERT((cnp->cn_flags & (LOCKPARENT | LOCKLEAF)) == LOCKPARENT,
|
|
|
|
("%s: FAILIFEXISTS must be passed with LOCKPARENT and without LOCKLEAF",
|
|
|
|
__func__));
|
|
|
|
}
|
2020-08-23 21:06:41 +00:00
|
|
|
#endif
|
2021-10-01 21:16:54 +00:00
|
|
|
ndp->ni_cnd.cn_cred = td->td_ucred;
|
2020-10-26 18:01:18 +00:00
|
|
|
KASSERT(ndp->ni_resflags == 0, ("%s: garbage in ni_resflags: %x\n",
|
|
|
|
__func__, ndp->ni_resflags));
|
2020-08-05 07:33:39 +00:00
|
|
|
KASSERT(cnp->cn_cred && td->td_proc, ("namei: bad cred/proc"));
|
2020-08-11 01:34:40 +00:00
|
|
|
KASSERT((cnp->cn_flags & NAMEI_INTERNAL_FLAGS) == 0,
|
|
|
|
("namei: unexpected flags: %" PRIx64 "\n",
|
|
|
|
cnp->cn_flags & NAMEI_INTERNAL_FLAGS));
|
2020-08-10 10:33:40 +00:00
|
|
|
if (cnp->cn_flags & NOCACHE)
|
|
|
|
KASSERT(cnp->cn_nameiop != LOOKUP,
|
|
|
|
("%s: NOCACHE passed with LOOKUP", __func__));
|
2020-07-25 10:37:15 +00:00
|
|
|
MPASS(ndp->ni_startdir == NULL || ndp->ni_startdir->v_type == VDIR ||
|
|
|
|
ndp->ni_startdir->v_type == VBAD);
|
|
|
|
|
2023-05-29 08:15:28 +00:00
|
|
|
restart:
|
2020-08-05 07:33:39 +00:00
|
|
|
ndp->ni_lcf = 0;
|
2021-01-23 13:40:48 +00:00
|
|
|
ndp->ni_loopcnt = 0;
|
2020-07-25 10:37:15 +00:00
|
|
|
ndp->ni_vp = NULL;
|
|
|
|
|
2020-12-06 04:59:24 +00:00
|
|
|
error = namei_getpath(ndp);
|
2020-08-05 07:33:39 +00:00
|
|
|
if (__predict_false(error != 0)) {
|
2021-03-07 14:29:09 +00:00
|
|
|
namei_cleanup_cnp(cnp);
|
|
|
|
SDT_PROBE4(vfs, namei, lookup, return, error, NULL,
|
|
|
|
false, ndp);
|
2020-07-25 10:37:15 +00:00
|
|
|
return (error);
|
|
|
|
}
|
|
|
|
|
2022-09-17 00:59:32 +00:00
|
|
|
cnp->cn_nameptr = cnp->cn_pnbuf;
|
|
|
|
|
2020-07-25 10:37:15 +00:00
|
|
|
#ifdef KTRACE
|
|
|
|
if (KTRPOINT(td, KTR_NAMEI)) {
|
|
|
|
ktrnamei(cnp->cn_pnbuf);
|
|
|
|
}
|
|
|
|
#endif
|
2021-10-16 18:47:34 +00:00
|
|
|
TSNAMEI(curthread->td_proc->p_pid, cnp->cn_pnbuf);
|
2020-07-25 10:37:15 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* First try looking up the target without locking any vnodes.
|
|
|
|
*
|
|
|
|
* We may need to start from scratch or pick up where it left off.
|
|
|
|
*/
|
|
|
|
error = cache_fplookup(ndp, &status, &pwd);
|
|
|
|
switch (status) {
|
|
|
|
case CACHE_FPL_STATUS_UNSET:
|
|
|
|
__assert_unreachable();
|
|
|
|
break;
|
|
|
|
case CACHE_FPL_STATUS_HANDLED:
|
2020-08-23 21:06:41 +00:00
|
|
|
if (error == 0)
|
|
|
|
NDVALIDATE(ndp);
|
2023-05-29 08:15:28 +00:00
|
|
|
else if (__predict_false(pwd->pwd_adir != pwd->pwd_rdir &&
|
|
|
|
(cnp->cn_flags & ISRESTARTED) == 0)) {
|
|
|
|
namei_cleanup_cnp(cnp);
|
|
|
|
NDRESTART(ndp);
|
|
|
|
goto restart;
|
|
|
|
}
|
2020-07-25 10:37:15 +00:00
|
|
|
return (error);
|
|
|
|
case CACHE_FPL_STATUS_PARTIAL:
|
2020-08-05 07:33:39 +00:00
|
|
|
TAILQ_INIT(&ndp->ni_cap_tracker);
|
2020-07-25 10:37:15 +00:00
|
|
|
dp = ndp->ni_startdir;
|
|
|
|
break;
|
2021-01-23 13:40:48 +00:00
|
|
|
case CACHE_FPL_STATUS_DESTROYED:
|
|
|
|
ndp->ni_loopcnt = 0;
|
|
|
|
error = namei_getpath(ndp);
|
|
|
|
if (__predict_false(error != 0)) {
|
2021-03-07 14:29:09 +00:00
|
|
|
namei_cleanup_cnp(cnp);
|
2021-01-23 13:40:48 +00:00
|
|
|
return (error);
|
|
|
|
}
|
2022-09-17 00:59:32 +00:00
|
|
|
cnp->cn_nameptr = cnp->cn_pnbuf;
|
2021-01-23 13:40:48 +00:00
|
|
|
/* FALLTHROUGH */
|
2020-07-25 10:37:15 +00:00
|
|
|
case CACHE_FPL_STATUS_ABORTED:
|
2020-08-05 07:33:39 +00:00
|
|
|
TAILQ_INIT(&ndp->ni_cap_tracker);
|
2021-01-23 13:40:48 +00:00
|
|
|
MPASS(ndp->ni_lcf == 0);
|
2021-09-26 13:00:24 +00:00
|
|
|
if (*cnp->cn_pnbuf == '\0') {
|
|
|
|
if ((cnp->cn_flags & EMPTYPATH) != 0) {
|
|
|
|
return (namei_emptypath(ndp));
|
|
|
|
}
|
|
|
|
namei_cleanup_cnp(cnp);
|
|
|
|
SDT_PROBE4(vfs, namei, lookup, return, ENOENT, NULL,
|
|
|
|
false, ndp);
|
|
|
|
return (ENOENT);
|
|
|
|
}
|
2020-07-25 10:37:15 +00:00
|
|
|
error = namei_setup(ndp, &dp, &pwd);
|
|
|
|
if (error != 0) {
|
|
|
|
namei_cleanup_cnp(cnp);
|
|
|
|
return (error);
|
|
|
|
}
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Locked lookup.
|
|
|
|
*/
|
1994-05-24 10:09:53 +00:00
|
|
|
for (;;) {
|
|
|
|
ndp->ni_startdir = dp;
|
2022-03-13 14:44:39 +00:00
|
|
|
error = vfs_lookup(ndp);
|
2023-05-29 08:15:28 +00:00
|
|
|
if (error != 0) {
|
|
|
|
if (__predict_false(pwd->pwd_adir != pwd->pwd_rdir &&
|
|
|
|
error == ENOENT &&
|
|
|
|
(cnp->cn_flags & ISRESTARTED) == 0)) {
|
|
|
|
nameicap_cleanup(ndp);
|
|
|
|
pwd_drop(pwd);
|
|
|
|
namei_cleanup_cnp(cnp);
|
|
|
|
NDRESTART(ndp);
|
|
|
|
goto restart;
|
|
|
|
} else
|
|
|
|
goto out;
|
|
|
|
}
|
2020-10-08 22:31:11 +00:00
|
|
|
|
1994-05-24 10:09:53 +00:00
|
|
|
/*
|
2009-05-29 09:52:13 +00:00
|
|
|
* If not a symbolic link, we're done.
|
1994-05-24 10:09:53 +00:00
|
|
|
*/
|
|
|
|
if ((cnp->cn_flags & ISSYMLINK) == 0) {
|
2021-01-12 13:09:55 +00:00
|
|
|
SDT_PROBE4(vfs, namei, lookup, return, error,
|
2022-09-13 23:18:30 +00:00
|
|
|
ndp->ni_vp, false, ndp);
|
2021-02-16 03:31:40 +00:00
|
|
|
nameicap_cleanup(ndp);
|
2020-03-01 21:53:46 +00:00
|
|
|
pwd_drop(pwd);
|
2022-09-13 23:18:30 +00:00
|
|
|
NDVALIDATE(ndp);
|
|
|
|
return (0);
|
1994-05-24 10:09:53 +00:00
|
|
|
}
|
2022-03-24 12:57:30 +00:00
|
|
|
error = namei_follow_link(ndp);
|
|
|
|
if (error != 0)
|
1994-05-24 10:09:53 +00:00
|
|
|
break;
|
|
|
|
vput(ndp->ni_vp);
|
|
|
|
dp = ndp->ni_dvp;
|
2015-07-09 15:06:58 +00:00
|
|
|
/*
|
|
|
|
* Check if root directory should replace current directory.
|
|
|
|
*/
|
|
|
|
cnp->cn_nameptr = cnp->cn_pnbuf;
|
|
|
|
if (*(cnp->cn_nameptr) == '/') {
|
2023-06-13 12:24:25 +00:00
|
|
|
/*
|
|
|
|
* Reset the lookup to start from the real root without
|
|
|
|
* origin path name reloading.
|
|
|
|
*/
|
|
|
|
if (__predict_false(ndp->ni_rootdir != pwd->pwd_rdir)) {
|
|
|
|
cnp->cn_flags |= ISRESTARTED;
|
|
|
|
ndp->ni_rootdir = pwd->pwd_rdir;
|
|
|
|
}
|
2015-07-09 15:06:58 +00:00
|
|
|
vrele(dp);
|
2020-03-01 21:54:28 +00:00
|
|
|
error = namei_handle_root(ndp, &dp);
|
2016-08-27 22:43:41 +00:00
|
|
|
if (error != 0)
|
|
|
|
goto out;
|
2015-07-09 15:06:58 +00:00
|
|
|
}
|
1994-05-24 10:09:53 +00:00
|
|
|
}
|
|
|
|
vput(ndp->ni_vp);
|
|
|
|
ndp->ni_vp = NULL;
|
2005-04-09 11:53:16 +00:00
|
|
|
vrele(ndp->ni_dvp);
|
2016-08-27 22:43:41 +00:00
|
|
|
out:
|
2018-11-11 00:04:36 +00:00
|
|
|
MPASS(error != 0);
|
2021-01-12 13:09:55 +00:00
|
|
|
SDT_PROBE4(vfs, namei, lookup, return, error, NULL, false, ndp);
|
2016-08-27 22:43:41 +00:00
|
|
|
namei_cleanup_cnp(cnp);
|
2021-02-16 03:31:40 +00:00
|
|
|
nameicap_cleanup(ndp);
|
2020-03-01 21:53:46 +00:00
|
|
|
pwd_drop(pwd);
|
1994-05-24 10:09:53 +00:00
|
|
|
return (error);
|
|
|
|
}
|
|
|
|
|
2006-09-13 18:39:09 +00:00
|
|
|
static int
|
2023-07-05 13:40:22 +00:00
|
|
|
enforce_lkflags(struct mount *mp, int lkflags)
|
2006-09-13 18:39:09 +00:00
|
|
|
{
|
2008-11-03 19:33:20 +00:00
|
|
|
|
2012-09-09 19:11:52 +00:00
|
|
|
if (mp == NULL || ((lkflags & LK_SHARED) &&
|
2021-09-18 10:46:03 +00:00
|
|
|
!(mp->mnt_kern_flag & MNTK_LOOKUP_SHARED))) {
|
2006-09-13 18:39:09 +00:00
|
|
|
lkflags &= ~LK_SHARED;
|
|
|
|
lkflags |= LK_EXCLUSIVE;
|
|
|
|
}
|
2014-11-02 13:10:31 +00:00
|
|
|
lkflags |= LK_NODDLKTREAT;
|
2008-11-03 19:33:20 +00:00
|
|
|
return (lkflags);
|
2006-09-13 18:39:09 +00:00
|
|
|
}
|
|
|
|
|
2009-03-11 14:13:47 +00:00
|
|
|
static __inline int
|
|
|
|
needs_exclusive_leaf(struct mount *mp, int flags)
|
|
|
|
{
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Intermediate nodes can use shared locks, we only need to
|
|
|
|
* force an exclusive lock for leaf nodes.
|
|
|
|
*/
|
|
|
|
if ((flags & (ISLASTCN | LOCKLEAF)) != (ISLASTCN | LOCKLEAF))
|
|
|
|
return (0);
|
|
|
|
|
|
|
|
/* Always use exclusive locks if LOCKSHARED isn't set. */
|
|
|
|
if (!(flags & LOCKSHARED))
|
|
|
|
return (1);
|
|
|
|
|
|
|
|
/*
|
|
|
|
* For lookups during open(), if the mount point supports
|
|
|
|
* extended shared operations, then use a shared lock for the
|
|
|
|
* leaf node, otherwise use an exclusive lock.
|
|
|
|
*/
|
2013-11-09 20:30:13 +00:00
|
|
|
if ((flags & ISOPEN) != 0)
|
|
|
|
return (!MNT_EXTENDED_SHARED(mp));
|
2009-03-11 14:13:47 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Lookup requests outside of open() that specify LOCKSHARED
|
|
|
|
* only need a shared lock on the leaf vnode.
|
|
|
|
*/
|
2009-03-11 14:39:55 +00:00
|
|
|
return (0);
|
2009-03-11 14:13:47 +00:00
|
|
|
}
|
|
|
|
|
2021-03-27 17:42:48 +00:00
|
|
|
/*
|
|
|
|
* Various filesystems expect to be able to copy a name component with length
|
|
|
|
* bounded by NAME_MAX into a directory entry buffer of size MAXNAMLEN. Make
|
|
|
|
* sure that these are the same size.
|
|
|
|
*/
|
|
|
|
_Static_assert(MAXNAMLEN == NAME_MAX,
|
|
|
|
"MAXNAMLEN and NAME_MAX have different values");
|
|
|
|
|
2022-03-11 15:51:39 +00:00
|
|
|
static int __noinline
|
|
|
|
vfs_lookup_degenerate(struct nameidata *ndp, struct vnode *dp, int wantparent)
|
|
|
|
{
|
|
|
|
struct componentname *cnp;
|
|
|
|
struct mount *mp;
|
|
|
|
int error;
|
|
|
|
|
|
|
|
cnp = &ndp->ni_cnd;
|
|
|
|
|
|
|
|
cnp->cn_flags |= ISLASTCN;
|
|
|
|
|
|
|
|
mp = atomic_load_ptr(&dp->v_mount);
|
|
|
|
if (needs_exclusive_leaf(mp, cnp->cn_flags)) {
|
|
|
|
cnp->cn_lkflags &= ~LK_SHARED;
|
|
|
|
cnp->cn_lkflags |= LK_EXCLUSIVE;
|
|
|
|
}
|
|
|
|
|
2023-07-05 13:40:22 +00:00
|
|
|
vn_lock(dp, enforce_lkflags(mp, cnp->cn_lkflags | LK_RETRY));
|
2022-03-11 15:51:39 +00:00
|
|
|
|
|
|
|
if (dp->v_type != VDIR) {
|
|
|
|
error = ENOTDIR;
|
|
|
|
goto bad;
|
|
|
|
}
|
|
|
|
if (cnp->cn_nameiop != LOOKUP) {
|
|
|
|
error = EISDIR;
|
|
|
|
goto bad;
|
|
|
|
}
|
|
|
|
if (wantparent) {
|
|
|
|
ndp->ni_dvp = dp;
|
|
|
|
VREF(dp);
|
|
|
|
}
|
|
|
|
ndp->ni_vp = dp;
|
2022-03-25 18:19:36 +00:00
|
|
|
cnp->cn_namelen = 0;
|
2022-03-11 15:51:39 +00:00
|
|
|
|
|
|
|
if (cnp->cn_flags & AUDITVNODE1)
|
|
|
|
AUDIT_ARG_VNODE1(dp);
|
|
|
|
else if (cnp->cn_flags & AUDITVNODE2)
|
|
|
|
AUDIT_ARG_VNODE2(dp);
|
|
|
|
|
|
|
|
if (!(cnp->cn_flags & (LOCKPARENT | LOCKLEAF)))
|
|
|
|
VOP_UNLOCK(dp);
|
|
|
|
return (0);
|
|
|
|
bad:
|
|
|
|
VOP_UNLOCK(dp);
|
|
|
|
return (error);
|
|
|
|
}
|
|
|
|
|
2022-03-13 17:36:51 +00:00
|
|
|
/*
|
|
|
|
* FAILIFEXISTS handling.
|
|
|
|
*
|
|
|
|
* XXX namei called with LOCKPARENT but not LOCKLEAF has the strange
|
|
|
|
* behaviour of leaving the vnode unlocked if the target is the same
|
|
|
|
* vnode as the parent.
|
|
|
|
*/
|
|
|
|
static int __noinline
|
|
|
|
vfs_lookup_failifexists(struct nameidata *ndp)
|
|
|
|
{
|
|
|
|
struct componentname *cnp __diagused;
|
|
|
|
|
|
|
|
cnp = &ndp->ni_cnd;
|
|
|
|
|
|
|
|
MPASS((cnp->cn_flags & ISSYMLINK) == 0);
|
|
|
|
if (ndp->ni_vp == ndp->ni_dvp)
|
|
|
|
vrele(ndp->ni_dvp);
|
|
|
|
else
|
|
|
|
vput(ndp->ni_dvp);
|
|
|
|
vrele(ndp->ni_vp);
|
|
|
|
ndp->ni_dvp = NULL;
|
|
|
|
ndp->ni_vp = NULL;
|
|
|
|
NDFREE_PNBUF(ndp);
|
|
|
|
return (EEXIST);
|
|
|
|
}
|
|
|
|
|
2023-07-05 23:01:17 +00:00
|
|
|
static int __noinline
|
|
|
|
vfs_lookup_cross_mount(struct nameidata *ndp)
|
|
|
|
{
|
|
|
|
struct componentname *cnp;
|
|
|
|
struct mount *mp;
|
|
|
|
struct vnode *dp, *tdp;
|
|
|
|
int error, crosslkflags;
|
|
|
|
bool crosslock;
|
|
|
|
|
|
|
|
cnp = &ndp->ni_cnd;
|
|
|
|
dp = ndp->ni_vp;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* The vnode has been mounted on, find the root of the mounted
|
|
|
|
* filesystem.
|
|
|
|
*/
|
2023-11-04 16:56:45 +00:00
|
|
|
do {
|
2023-07-05 23:01:17 +00:00
|
|
|
mp = dp->v_mountedhere;
|
|
|
|
ASSERT_VOP_LOCKED(dp, __func__);
|
|
|
|
VNPASS((vn_irflag_read(dp) & VIRF_MOUNTPOINT) != 0 && mp != NULL, dp);
|
|
|
|
|
|
|
|
crosslock = (dp->v_vflag & VV_CROSSLOCK) != 0;
|
|
|
|
crosslkflags = enforce_lkflags(mp, cnp->cn_lkflags);
|
|
|
|
if (__predict_false(crosslock)) {
|
|
|
|
/*
|
|
|
|
* We are going to be holding the vnode lock, which
|
|
|
|
* in this case is shared by the root vnode of the
|
|
|
|
* filesystem mounted at mp, across the call to
|
|
|
|
* VFS_ROOT(). Make the situation clear to the
|
|
|
|
* filesystem by passing LK_CANRECURSE if the
|
|
|
|
* lock is held exclusive, or by clearinng
|
|
|
|
* LK_NODDLKTREAT to allow recursion on the shared
|
|
|
|
* lock in the presence of an exclusive waiter.
|
|
|
|
*/
|
|
|
|
if (VOP_ISLOCKED(dp) == LK_EXCLUSIVE) {
|
|
|
|
crosslkflags &= ~LK_SHARED;
|
|
|
|
crosslkflags |= LK_EXCLUSIVE | LK_CANRECURSE;
|
|
|
|
} else if ((crosslkflags & LK_EXCLUSIVE) != 0) {
|
|
|
|
error = vn_lock(dp, LK_UPGRADE);
|
2023-09-22 20:57:20 +00:00
|
|
|
if (error != 0) {
|
|
|
|
MPASS(error == ENOENT);
|
|
|
|
vrele(dp);
|
|
|
|
if (dp != ndp->ni_dvp)
|
|
|
|
vput(ndp->ni_dvp);
|
|
|
|
else
|
|
|
|
vrele(ndp->ni_dvp);
|
2023-07-05 23:01:17 +00:00
|
|
|
break;
|
2023-09-22 20:57:20 +00:00
|
|
|
}
|
2023-07-05 23:01:17 +00:00
|
|
|
if (dp->v_mountedhere != mp) {
|
2023-11-04 16:56:45 +00:00
|
|
|
/*
|
|
|
|
* Note that we rely on the
|
|
|
|
* VIRF_MOUNTPOINT loop condition to
|
|
|
|
* ensure we stop iterating if dp is
|
|
|
|
* no longer a mountpoint at all.
|
|
|
|
*/
|
2023-07-05 23:01:17 +00:00
|
|
|
continue;
|
|
|
|
}
|
|
|
|
} else
|
|
|
|
crosslkflags &= ~LK_NODDLKTREAT;
|
|
|
|
}
|
|
|
|
if (vfs_busy(mp, 0) != 0)
|
|
|
|
continue;
|
|
|
|
if (__predict_true(!crosslock))
|
|
|
|
vput(dp);
|
|
|
|
if (dp != ndp->ni_dvp)
|
|
|
|
vput(ndp->ni_dvp);
|
|
|
|
else
|
|
|
|
vrele(ndp->ni_dvp);
|
|
|
|
vrefact(vp_crossmp);
|
|
|
|
ndp->ni_dvp = vp_crossmp;
|
|
|
|
error = VFS_ROOT(mp, crosslkflags, &tdp);
|
|
|
|
vfs_unbusy(mp);
|
|
|
|
if (__predict_false(crosslock))
|
|
|
|
vput(dp);
|
|
|
|
if (vn_lock(vp_crossmp, LK_SHARED | LK_NOWAIT))
|
|
|
|
panic("vp_crossmp exclusively locked or reclaimed");
|
|
|
|
if (error != 0)
|
|
|
|
break;
|
|
|
|
ndp->ni_vp = dp = tdp;
|
2023-11-04 16:56:45 +00:00
|
|
|
} while ((vn_irflag_read(dp) & VIRF_MOUNTPOINT) != 0);
|
2023-07-05 23:01:17 +00:00
|
|
|
|
|
|
|
return (error);
|
|
|
|
}
|
|
|
|
|
1994-05-24 10:09:53 +00:00
|
|
|
/*
|
|
|
|
* Search a pathname.
|
|
|
|
* This is a very central and rather complicated routine.
|
|
|
|
*
|
2023-06-27 22:31:50 +00:00
|
|
|
* The pathname is pointed to by cn_nameptr and is of length ni_pathlen.
|
1994-05-24 10:09:53 +00:00
|
|
|
* The starting directory is taken from ni_startdir. The pathname is
|
2023-06-27 22:31:50 +00:00
|
|
|
* descended until done, or a symbolic link is encountered. The cn_flags
|
|
|
|
* has ISLASTCN or'ed if the path is completed or ISSYMLINK or'ed if a
|
1994-05-24 10:09:53 +00:00
|
|
|
* symbolic link needing interpretation is encountered.
|
|
|
|
*
|
2023-06-27 22:31:50 +00:00
|
|
|
* The cn_nameiop is LOOKUP, CREATE, RENAME, or DELETE depending on
|
1994-05-24 10:09:53 +00:00
|
|
|
* whether the name is to be looked up, created, renamed, or deleted.
|
|
|
|
* When CREATE, RENAME, or DELETE is specified, information usable in
|
|
|
|
* creating, renaming, or deleting a directory entry may be calculated.
|
2023-06-27 22:31:50 +00:00
|
|
|
* If cn_flags has LOCKPARENT or'ed into it, the parent directory is returned
|
|
|
|
* locked. If it has WANTPARENT or'ed into it, the parent directory is
|
1994-05-24 10:09:53 +00:00
|
|
|
* returned unlocked. Otherwise the parent directory is not returned. If
|
2023-06-27 22:31:50 +00:00
|
|
|
* the target of the pathname exists and LOCKLEAF is or'ed into the cn_flags
|
1994-05-24 10:09:53 +00:00
|
|
|
* the target is returned locked, otherwise it is returned unlocked.
|
1995-05-30 08:16:23 +00:00
|
|
|
*
|
1994-05-24 10:09:53 +00:00
|
|
|
* Overall outline of lookup:
|
|
|
|
*
|
2023-06-27 22:31:50 +00:00
|
|
|
* handle degenerate case where name is null string
|
|
|
|
*
|
1994-05-24 10:09:53 +00:00
|
|
|
* dirloop:
|
2023-06-27 22:31:50 +00:00
|
|
|
* identify next component of name at ndp->ni_cnd.cn_nameptr
|
2023-06-27 22:31:50 +00:00
|
|
|
* handle .. special cases related to capabilities, chroot, jail
|
1994-05-24 10:09:53 +00:00
|
|
|
* if .. and crossing mount points and on mounted filesys, find parent
|
|
|
|
* call VOP_LOOKUP routine for next component name
|
|
|
|
* directory vnode returned in ni_dvp, unlocked unless LOCKPARENT set
|
|
|
|
* component vnode returned in ni_vp (if it exists), locked.
|
|
|
|
* if result vnode is mounted on and crossing mount points,
|
|
|
|
* find mounted on vnode
|
|
|
|
* if more components of name, do next level at dirloop
|
2023-06-27 22:31:50 +00:00
|
|
|
* if VOP_LOOKUP returns ERELOOKUP, repeat the same level at dirloop
|
1994-05-24 10:09:53 +00:00
|
|
|
* return the answer in ni_vp, locked if LOCKLEAF set
|
|
|
|
* if LOCKPARENT set, return locked parent in ni_dvp
|
|
|
|
* if WANTPARENT set, return unlocked parent in ni_dvp
|
|
|
|
*/
|
|
|
|
int
|
2022-03-13 14:44:39 +00:00
|
|
|
vfs_lookup(struct nameidata *ndp)
|
1994-05-24 10:09:53 +00:00
|
|
|
{
|
2017-01-04 14:43:57 +00:00
|
|
|
char *cp; /* pointer into pathname argument */
|
|
|
|
char *prev_ni_next; /* saved ndp->ni_next */
|
2021-05-25 17:34:26 +00:00
|
|
|
char *nulchar; /* location of '\0' in cn_pnbuf */
|
2022-03-24 13:17:31 +00:00
|
|
|
char *lastchar; /* location of the last character */
|
2016-04-15 16:10:11 +00:00
|
|
|
struct vnode *dp = NULL; /* the directory we are searching */
|
1994-05-24 10:09:53 +00:00
|
|
|
struct vnode *tdp; /* saved dp */
|
2009-05-27 14:11:23 +00:00
|
|
|
struct prison *pr;
|
2017-01-04 14:43:57 +00:00
|
|
|
size_t prev_ni_pathlen; /* saved ndp->ni_pathlen */
|
1994-05-24 10:09:53 +00:00
|
|
|
int docache; /* == 0 do not cache last component */
|
|
|
|
int wantparent; /* 1 => wantparent or lockparent flag */
|
|
|
|
int rdonly; /* lookup read-only flag bit */
|
|
|
|
int error = 0;
|
2016-03-12 07:54:42 +00:00
|
|
|
int relookup = 0; /* do not consume the path component */
|
1994-05-24 10:09:53 +00:00
|
|
|
struct componentname *cnp = &ndp->ni_cnd;
|
2006-09-13 18:39:09 +00:00
|
|
|
int lkflags_save;
|
2012-01-01 18:45:59 +00:00
|
|
|
int ni_dvp_unlocked;
|
2020-07-10 09:01:36 +00:00
|
|
|
|
1994-05-24 10:09:53 +00:00
|
|
|
/*
|
|
|
|
* Setup: break out flag bits into variables.
|
|
|
|
*/
|
2012-01-01 18:45:59 +00:00
|
|
|
ni_dvp_unlocked = 0;
|
1994-05-24 10:09:53 +00:00
|
|
|
wantparent = cnp->cn_flags & (LOCKPARENT | WANTPARENT);
|
2005-03-28 13:56:56 +00:00
|
|
|
KASSERT(cnp->cn_nameiop == LOOKUP || wantparent,
|
|
|
|
("CREATE, DELETE, RENAME require LOCKPARENT or WANTPARENT."));
|
2020-08-27 22:14:58 +00:00
|
|
|
/*
|
|
|
|
* When set to zero, docache causes the last component of the
|
|
|
|
* pathname to be deleted from the cache and the full lookup
|
|
|
|
* of the name to be done (via VOP_CACHEDLOOKUP()). Often
|
|
|
|
* filesystems need some pre-computed values that are made
|
|
|
|
* during the full lookup, for instance UFS sets dp->i_offset.
|
|
|
|
*
|
|
|
|
* The docache variable is set to zero when requested by the
|
|
|
|
* NOCACHE flag and for all modifying operations except CREATE.
|
|
|
|
*/
|
1994-05-24 10:09:53 +00:00
|
|
|
docache = (cnp->cn_flags & NOCACHE) ^ NOCACHE;
|
|
|
|
if (cnp->cn_nameiop == DELETE ||
|
1997-02-18 06:46:41 +00:00
|
|
|
(wantparent && cnp->cn_nameiop != CREATE &&
|
|
|
|
cnp->cn_nameiop != LOOKUP))
|
1994-05-24 10:09:53 +00:00
|
|
|
docache = 0;
|
|
|
|
rdonly = cnp->cn_flags & RDONLY;
|
|
|
|
cnp->cn_flags &= ~ISSYMLINK;
|
2005-03-29 10:07:15 +00:00
|
|
|
ndp->ni_dvp = NULL;
|
2022-03-11 15:51:39 +00:00
|
|
|
|
|
|
|
cnp->cn_lkflags = LK_SHARED;
|
|
|
|
dp = ndp->ni_startdir;
|
|
|
|
ndp->ni_startdir = NULLVP;
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Leading slashes, if any, are supposed to be skipped by the caller.
|
|
|
|
*/
|
|
|
|
MPASS(cnp->cn_nameptr[0] != '/');
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Check for degenerate name (e.g. / or "") which is a way of talking
|
|
|
|
* about a directory, e.g. like "/." or ".".
|
|
|
|
*/
|
|
|
|
if (__predict_false(cnp->cn_nameptr[0] == '\0')) {
|
|
|
|
error = vfs_lookup_degenerate(ndp, dp, wantparent);
|
|
|
|
if (error == 0)
|
|
|
|
goto success_right_lock;
|
|
|
|
goto bad_unlocked;
|
|
|
|
}
|
|
|
|
|
2022-03-24 13:17:31 +00:00
|
|
|
/*
|
|
|
|
* Nul-out trailing slashes (e.g., "foo///" -> "foo").
|
|
|
|
*
|
|
|
|
* This must be done before VOP_LOOKUP() because some fs's don't know
|
|
|
|
* about trailing slashes. Remember if there were trailing slashes to
|
|
|
|
* handle symlinks, existing non-directories and non-existing files
|
|
|
|
* that won't be directories specially later.
|
|
|
|
*/
|
|
|
|
MPASS(ndp->ni_pathlen >= 2);
|
|
|
|
lastchar = &cnp->cn_nameptr[ndp->ni_pathlen - 2];
|
|
|
|
if (*lastchar == '/') {
|
|
|
|
while (lastchar >= cnp->cn_pnbuf) {
|
|
|
|
*lastchar = '\0';
|
|
|
|
lastchar--;
|
|
|
|
ndp->ni_pathlen--;
|
|
|
|
if (*lastchar != '/') {
|
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
cnp->cn_flags |= TRAILINGSLASH;
|
|
|
|
}
|
|
|
|
|
2005-03-29 10:07:15 +00:00
|
|
|
/*
|
|
|
|
* We use shared locks until we hit the parent of the last cn then
|
|
|
|
* we adjust based on the requesting flags.
|
|
|
|
*/
|
2008-01-10 01:10:58 +00:00
|
|
|
vn_lock(dp,
|
2023-07-05 13:40:22 +00:00
|
|
|
enforce_lkflags(dp->v_mount, cnp->cn_lkflags | LK_RETRY));
|
1994-05-24 10:09:53 +00:00
|
|
|
|
|
|
|
dirloop:
|
|
|
|
/*
|
|
|
|
* Search a new directory.
|
|
|
|
*
|
|
|
|
* The last component of the filename is left accessible via
|
2022-09-17 09:10:38 +00:00
|
|
|
* cnp->cn_nameptr. It has to be freed with a call to NDFREE*.
|
2021-05-25 17:34:26 +00:00
|
|
|
*
|
|
|
|
* Store / as a temporary sentinel so that we only have one character
|
|
|
|
* to test for. Pathnames tend to be short so this should not be
|
|
|
|
* resulting in cache misses.
|
1994-05-24 10:09:53 +00:00
|
|
|
*/
|
2021-05-25 17:34:26 +00:00
|
|
|
nulchar = &cnp->cn_nameptr[ndp->ni_pathlen - 1];
|
|
|
|
KASSERT(*nulchar == '\0',
|
|
|
|
("%s: expected nul at %p; string [%s]\n", __func__, nulchar,
|
|
|
|
cnp->cn_pnbuf));
|
|
|
|
*nulchar = '/';
|
|
|
|
for (cp = cnp->cn_nameptr; *cp != '/'; cp++) {
|
|
|
|
KASSERT(*cp != '\0',
|
|
|
|
("%s: encountered unexpected nul; string [%s]\n", __func__,
|
|
|
|
cnp->cn_nameptr));
|
1999-10-03 12:18:29 +00:00
|
|
|
continue;
|
2021-05-25 17:34:26 +00:00
|
|
|
}
|
|
|
|
*nulchar = '\0';
|
1994-05-24 10:09:53 +00:00
|
|
|
cnp->cn_namelen = cp - cnp->cn_nameptr;
|
2022-03-26 10:26:59 +00:00
|
|
|
if (__predict_false(cnp->cn_namelen > NAME_MAX)) {
|
1994-05-24 10:09:53 +00:00
|
|
|
error = ENAMETOOLONG;
|
|
|
|
goto bad;
|
|
|
|
}
|
2017-01-04 14:43:57 +00:00
|
|
|
prev_ni_pathlen = ndp->ni_pathlen;
|
1994-05-24 10:09:53 +00:00
|
|
|
ndp->ni_pathlen -= cnp->cn_namelen;
|
2017-01-04 14:43:57 +00:00
|
|
|
KASSERT(ndp->ni_pathlen <= PATH_MAX,
|
|
|
|
("%s: ni_pathlen underflow to %zd\n", __func__, ndp->ni_pathlen));
|
|
|
|
prev_ni_next = ndp->ni_next;
|
1994-05-24 10:09:53 +00:00
|
|
|
ndp->ni_next = cp;
|
1995-07-31 00:35:58 +00:00
|
|
|
|
2022-03-26 10:26:59 +00:00
|
|
|
/*
|
|
|
|
* Something else should be clearing this.
|
|
|
|
*/
|
|
|
|
cnp->cn_flags &= ~(ISDOTDOT|ISLASTCN);
|
|
|
|
|
1994-05-24 10:09:53 +00:00
|
|
|
cnp->cn_flags |= MAKEENTRY;
|
|
|
|
if (*cp == '\0' && docache == 0)
|
|
|
|
cnp->cn_flags &= ~MAKEENTRY;
|
|
|
|
if (cnp->cn_namelen == 2 &&
|
|
|
|
cnp->cn_nameptr[1] == '.' && cnp->cn_nameptr[0] == '.')
|
|
|
|
cnp->cn_flags |= ISDOTDOT;
|
2022-03-26 10:26:59 +00:00
|
|
|
if (*ndp->ni_next == 0) {
|
1994-05-24 10:09:53 +00:00
|
|
|
cnp->cn_flags |= ISLASTCN;
|
|
|
|
|
2022-03-26 10:26:59 +00:00
|
|
|
if (__predict_false(cnp->cn_namelen == 1 && cnp->cn_nameptr[0] == '.' &&
|
|
|
|
(cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME))) {
|
|
|
|
error = EINVAL;
|
|
|
|
goto bad;
|
|
|
|
}
|
2009-11-10 11:50:37 +00:00
|
|
|
}
|
1994-05-24 10:09:53 +00:00
|
|
|
|
2016-11-02 12:43:15 +00:00
|
|
|
nameicap_tracker_add(ndp, dp);
|
|
|
|
|
1994-05-24 10:09:53 +00:00
|
|
|
/*
|
2022-03-11 15:51:39 +00:00
|
|
|
* Make sure degenerate names don't get here, their handling was
|
|
|
|
* previously found in this spot.
|
1994-05-24 10:09:53 +00:00
|
|
|
*/
|
2022-03-11 15:51:39 +00:00
|
|
|
MPASS(cnp->cn_nameptr[0] != '\0');
|
1994-05-24 10:09:53 +00:00
|
|
|
|
|
|
|
/*
|
2011-08-13 09:21:16 +00:00
|
|
|
* Handle "..": five special cases.
|
2016-11-02 12:43:15 +00:00
|
|
|
* 0. If doing a capability lookup and lookup_cap_dotdot is
|
|
|
|
* disabled, return ENOTCAPABLE.
|
2006-01-21 19:57:56 +00:00
|
|
|
* 1. Return an error if this is the last component of
|
|
|
|
* the name and the operation is DELETE or RENAME.
|
|
|
|
* 2. If at root directory (e.g. after chroot)
|
1994-05-24 10:09:53 +00:00
|
|
|
* or at absolute root directory
|
|
|
|
* then ignore it so can't get out.
|
2006-01-21 19:57:56 +00:00
|
|
|
* 3. If this vnode is the root of a mounted
|
1994-05-24 10:09:53 +00:00
|
|
|
* filesystem, then replace it with the
|
|
|
|
* vnode which was mounted on so we take the
|
2002-05-16 21:28:32 +00:00
|
|
|
* .. in the other filesystem.
|
2006-01-21 19:57:56 +00:00
|
|
|
* 4. If the vnode is the top directory of
|
1999-09-25 14:14:21 +00:00
|
|
|
* the jail or chroot, don't let them out.
|
2016-11-02 12:43:15 +00:00
|
|
|
* 5. If doing a capability lookup and lookup_cap_dotdot is
|
|
|
|
* enabled, return ENOTCAPABLE if the lookup would escape
|
|
|
|
* from the initial file descriptor directory. Checks are
|
|
|
|
* done by ensuring that namei() already traversed the
|
|
|
|
* result of dotdot lookup.
|
1994-05-24 10:09:53 +00:00
|
|
|
*/
|
|
|
|
if (cnp->cn_flags & ISDOTDOT) {
|
2024-04-06 18:31:25 +00:00
|
|
|
if (__predict_false((ndp->ni_lcf & (NI_LCF_STRICTREL_KTR |
|
|
|
|
NI_LCF_CAP_DOTDOT_KTR)) == NI_LCF_STRICTREL_KTR))
|
|
|
|
NI_CAP_VIOLATION(ndp, cnp->cn_pnbuf);
|
|
|
|
if (__predict_false((ndp->ni_lcf & (NI_LCF_STRICTREL |
|
|
|
|
NI_LCF_CAP_DOTDOT)) == NI_LCF_STRICTREL)) {
|
2011-08-13 09:21:16 +00:00
|
|
|
error = ENOTCAPABLE;
|
|
|
|
goto bad;
|
|
|
|
}
|
2006-01-21 19:57:56 +00:00
|
|
|
if ((cnp->cn_flags & ISLASTCN) != 0 &&
|
|
|
|
(cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
|
2006-01-22 19:37:02 +00:00
|
|
|
error = EINVAL;
|
2006-01-21 19:57:56 +00:00
|
|
|
goto bad;
|
|
|
|
}
|
1994-05-24 10:09:53 +00:00
|
|
|
for (;;) {
|
2009-05-27 14:11:23 +00:00
|
|
|
for (pr = cnp->cn_cred->cr_prison; pr != NULL;
|
|
|
|
pr = pr->pr_parent)
|
|
|
|
if (dp == pr->pr_root)
|
|
|
|
break;
|
2023-04-23 23:21:42 +00:00
|
|
|
bool isroot = dp == ndp->ni_rootdir ||
|
|
|
|
dp == ndp->ni_topdir || dp == rootvnode ||
|
|
|
|
pr != NULL;
|
2024-04-06 18:31:25 +00:00
|
|
|
if (__predict_false(isroot && (ndp->ni_lcf &
|
|
|
|
(NI_LCF_STRICTREL | NI_LCF_STRICTREL_KTR)) != 0)) {
|
|
|
|
if ((ndp->ni_lcf & NI_LCF_STRICTREL_KTR) != 0)
|
|
|
|
NI_CAP_VIOLATION(ndp, cnp->cn_pnbuf);
|
|
|
|
if ((ndp->ni_lcf & NI_LCF_STRICTREL) != 0) {
|
|
|
|
error = ENOTCAPABLE;
|
|
|
|
goto capdotdot;
|
|
|
|
}
|
2023-04-23 23:21:42 +00:00
|
|
|
}
|
|
|
|
if (isroot || ((dp->v_vflag & VV_ROOT) != 0 &&
|
|
|
|
(cnp->cn_flags & NOCROSSMOUNT) != 0)) {
|
1994-05-24 10:09:53 +00:00
|
|
|
ndp->ni_dvp = dp;
|
|
|
|
ndp->ni_vp = dp;
|
|
|
|
VREF(dp);
|
|
|
|
goto nextname;
|
|
|
|
}
|
2007-02-15 09:53:49 +00:00
|
|
|
if ((dp->v_vflag & VV_ROOT) == 0)
|
1994-05-24 10:09:53 +00:00
|
|
|
break;
|
2019-12-08 21:30:04 +00:00
|
|
|
if (VN_IS_DOOMED(dp)) { /* forced unmount */
|
2009-03-24 18:16:42 +00:00
|
|
|
error = ENOENT;
|
2000-11-30 20:04:44 +00:00
|
|
|
goto bad;
|
|
|
|
}
|
1994-05-24 10:09:53 +00:00
|
|
|
tdp = dp;
|
|
|
|
dp = dp->v_mount->mnt_vnodecovered;
|
|
|
|
VREF(dp);
|
2005-04-09 11:53:16 +00:00
|
|
|
vput(tdp);
|
2008-01-10 01:10:58 +00:00
|
|
|
vn_lock(dp,
|
2023-07-05 13:40:22 +00:00
|
|
|
enforce_lkflags(dp->v_mount, cnp->cn_lkflags |
|
|
|
|
LK_RETRY));
|
2016-11-02 12:43:15 +00:00
|
|
|
error = nameicap_check_dotdot(ndp, dp);
|
|
|
|
if (error != 0) {
|
2023-04-23 23:21:42 +00:00
|
|
|
capdotdot:
|
2016-11-02 12:43:15 +00:00
|
|
|
goto bad;
|
|
|
|
}
|
1994-05-24 10:09:53 +00:00
|
|
|
}
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* We now have a segment name to search for, and a directory to search.
|
|
|
|
*/
|
|
|
|
unionlookup:
|
2002-08-01 01:21:40 +00:00
|
|
|
#ifdef MAC
|
2021-10-01 21:16:54 +00:00
|
|
|
error = mac_vnode_check_lookup(cnp->cn_cred, dp, cnp);
|
2022-03-26 10:26:59 +00:00
|
|
|
if (__predict_false(error))
|
2020-02-13 22:22:55 +00:00
|
|
|
goto bad;
|
2002-08-01 01:21:40 +00:00
|
|
|
#endif
|
1994-05-24 10:09:53 +00:00
|
|
|
ndp->ni_dvp = dp;
|
1997-02-10 02:22:35 +00:00
|
|
|
ndp->ni_vp = NULL;
|
1997-04-04 17:46:21 +00:00
|
|
|
ASSERT_VOP_LOCKED(dp, "lookup");
|
2005-03-29 10:07:15 +00:00
|
|
|
/*
|
|
|
|
* If we have a shared lock we may need to upgrade the lock for the
|
|
|
|
* last operation.
|
|
|
|
*/
|
2016-11-30 02:14:53 +00:00
|
|
|
if ((cnp->cn_flags & LOCKPARENT) && (cnp->cn_flags & ISLASTCN) &&
|
|
|
|
dp != vp_crossmp && VOP_ISLOCKED(dp) == LK_SHARED)
|
2016-11-30 02:17:03 +00:00
|
|
|
vn_lock(dp, LK_UPGRADE|LK_RETRY);
|
2019-12-08 21:30:04 +00:00
|
|
|
if (VN_IS_DOOMED(dp)) {
|
2013-04-01 09:59:38 +00:00
|
|
|
error = ENOENT;
|
|
|
|
goto bad;
|
|
|
|
}
|
2005-03-29 10:07:15 +00:00
|
|
|
/*
|
|
|
|
* If we're looking up the last component and we need an exclusive
|
|
|
|
* lock, adjust our lkflags.
|
|
|
|
*/
|
2009-03-11 14:13:47 +00:00
|
|
|
if (needs_exclusive_leaf(dp->v_mount, cnp->cn_flags))
|
2005-03-29 10:07:15 +00:00
|
|
|
cnp->cn_lkflags = LK_EXCLUSIVE;
|
2006-09-13 18:39:09 +00:00
|
|
|
lkflags_save = cnp->cn_lkflags;
|
2023-07-05 13:40:22 +00:00
|
|
|
cnp->cn_lkflags = enforce_lkflags(dp->v_mount, cnp->cn_lkflags);
|
2016-03-12 09:05:43 +00:00
|
|
|
error = VOP_LOOKUP(dp, &ndp->ni_vp, cnp);
|
|
|
|
cnp->cn_lkflags = lkflags_save;
|
|
|
|
if (error != 0) {
|
1999-01-08 17:31:30 +00:00
|
|
|
KASSERT(ndp->ni_vp == NULL, ("leaf should be empty"));
|
1994-05-24 10:09:53 +00:00
|
|
|
if ((error == ENOENT) &&
|
2002-08-04 10:29:36 +00:00
|
|
|
(dp->v_vflag & VV_ROOT) && (dp->v_mount != NULL) &&
|
1994-05-24 10:09:53 +00:00
|
|
|
(dp->v_mount->mnt_flag & MNT_UNION)) {
|
|
|
|
tdp = dp;
|
|
|
|
dp = dp->v_mount->mnt_vnodecovered;
|
|
|
|
VREF(dp);
|
2005-04-09 11:53:16 +00:00
|
|
|
vput(tdp);
|
2008-01-10 01:10:58 +00:00
|
|
|
vn_lock(dp,
|
2023-07-05 13:40:22 +00:00
|
|
|
enforce_lkflags(dp->v_mount, cnp->cn_lkflags |
|
|
|
|
LK_RETRY));
|
2016-11-02 12:43:15 +00:00
|
|
|
nameicap_tracker_add(ndp, dp);
|
1994-05-24 10:09:53 +00:00
|
|
|
goto unionlookup;
|
|
|
|
}
|
|
|
|
|
2016-03-12 07:54:42 +00:00
|
|
|
if (error == ERELOOKUP) {
|
|
|
|
vref(dp);
|
|
|
|
ndp->ni_vp = dp;
|
|
|
|
error = 0;
|
|
|
|
relookup = 1;
|
|
|
|
goto good;
|
|
|
|
}
|
|
|
|
|
1994-05-24 10:09:53 +00:00
|
|
|
if (error != EJUSTRETURN)
|
|
|
|
goto bad;
|
|
|
|
/*
|
2009-06-06 00:49:49 +00:00
|
|
|
* At this point, we know we're at the end of the
|
|
|
|
* pathname. If creating / renaming, we can consider
|
|
|
|
* allowing the file or directory to be created / renamed,
|
|
|
|
* provided we're not on a read-only filesystem.
|
1994-05-24 10:09:53 +00:00
|
|
|
*/
|
1995-10-22 09:32:48 +00:00
|
|
|
if (rdonly) {
|
1994-05-24 10:09:53 +00:00
|
|
|
error = EROFS;
|
|
|
|
goto bad;
|
|
|
|
}
|
2009-06-06 00:49:49 +00:00
|
|
|
/* trailing slash only allowed for directories */
|
|
|
|
if ((cnp->cn_flags & TRAILINGSLASH) &&
|
|
|
|
!(cnp->cn_flags & WILLBEDIR)) {
|
1995-07-31 00:35:58 +00:00
|
|
|
error = ENOENT;
|
|
|
|
goto bad;
|
|
|
|
}
|
2005-03-28 09:24:50 +00:00
|
|
|
if ((cnp->cn_flags & LOCKPARENT) == 0)
|
2020-01-03 22:29:58 +00:00
|
|
|
VOP_UNLOCK(dp);
|
1994-05-24 10:09:53 +00:00
|
|
|
/*
|
|
|
|
* We return with ni_vp NULL to indicate that the entry
|
|
|
|
* doesn't currently exist, leaving a pointer to the
|
2006-08-05 21:08:47 +00:00
|
|
|
* (possibly locked) directory vnode in ndp->ni_dvp.
|
1994-05-24 10:09:53 +00:00
|
|
|
*/
|
2005-01-24 10:27:05 +00:00
|
|
|
goto success;
|
2016-03-12 09:05:43 +00:00
|
|
|
}
|
2016-03-12 07:54:42 +00:00
|
|
|
|
|
|
|
good:
|
1994-05-24 10:09:53 +00:00
|
|
|
dp = ndp->ni_vp;
|
1995-07-31 00:35:58 +00:00
|
|
|
|
2022-10-20 03:33:19 +00:00
|
|
|
/*
|
|
|
|
* Check for symbolic link
|
|
|
|
*/
|
|
|
|
if ((dp->v_type == VLNK) &&
|
|
|
|
((cnp->cn_flags & FOLLOW) || (cnp->cn_flags & TRAILINGSLASH) ||
|
|
|
|
*ndp->ni_next == '/')) {
|
|
|
|
cnp->cn_flags |= ISSYMLINK;
|
|
|
|
if (VN_IS_DOOMED(dp)) {
|
|
|
|
/*
|
|
|
|
* We can't know whether the directory was mounted with
|
|
|
|
* NOSYMFOLLOW, so we can't follow safely.
|
|
|
|
*/
|
|
|
|
error = ENOENT;
|
|
|
|
goto bad2;
|
|
|
|
}
|
|
|
|
if (dp->v_mount->mnt_flag & MNT_NOSYMFOLLOW) {
|
|
|
|
error = EACCES;
|
|
|
|
goto bad2;
|
|
|
|
}
|
|
|
|
/*
|
|
|
|
* Symlink code always expects an unlocked dvp.
|
|
|
|
*/
|
|
|
|
if (ndp->ni_dvp != ndp->ni_vp) {
|
|
|
|
VOP_UNLOCK(ndp->ni_dvp);
|
|
|
|
ni_dvp_unlocked = 1;
|
|
|
|
}
|
|
|
|
goto success;
|
2023-07-05 23:01:17 +00:00
|
|
|
}
|
2022-10-20 03:33:19 +00:00
|
|
|
|
2023-07-05 23:01:17 +00:00
|
|
|
if ((vn_irflag_read(dp) & VIRF_MOUNTPOINT) != 0 &&
|
|
|
|
(cnp->cn_flags & NOCROSSMOUNT) == 0) {
|
|
|
|
error = vfs_lookup_cross_mount(ndp);
|
2023-07-05 21:52:07 +00:00
|
|
|
if (error != 0)
|
|
|
|
goto bad_unlocked;
|
2023-07-05 23:01:17 +00:00
|
|
|
/*
|
|
|
|
* FALLTHROUGH to nextname
|
|
|
|
*/
|
|
|
|
dp = ndp->ni_vp;
|
|
|
|
}
|
1995-08-24 10:17:39 +00:00
|
|
|
|
1994-05-24 10:09:53 +00:00
|
|
|
nextname:
|
|
|
|
/*
|
2009-06-06 00:49:49 +00:00
|
|
|
* Not a symbolic link that we will follow. Continue with the
|
|
|
|
* next component if there is any; otherwise, we're done.
|
1994-05-24 10:09:53 +00:00
|
|
|
*/
|
2005-03-28 09:24:50 +00:00
|
|
|
KASSERT((cnp->cn_flags & ISLASTCN) || *ndp->ni_next == '/',
|
|
|
|
("lookup: invalid path state."));
|
2016-03-12 07:54:42 +00:00
|
|
|
if (relookup) {
|
|
|
|
relookup = 0;
|
2017-01-04 14:43:57 +00:00
|
|
|
ndp->ni_pathlen = prev_ni_pathlen;
|
|
|
|
ndp->ni_next = prev_ni_next;
|
2016-03-12 07:54:42 +00:00
|
|
|
if (ndp->ni_dvp != dp)
|
|
|
|
vput(ndp->ni_dvp);
|
|
|
|
else
|
|
|
|
vrele(ndp->ni_dvp);
|
|
|
|
goto dirloop;
|
|
|
|
}
|
2016-11-02 12:43:15 +00:00
|
|
|
if (cnp->cn_flags & ISDOTDOT) {
|
|
|
|
error = nameicap_check_dotdot(ndp, ndp->ni_vp);
|
2024-04-06 18:31:25 +00:00
|
|
|
if (error != 0)
|
2016-11-02 12:43:15 +00:00
|
|
|
goto bad2;
|
|
|
|
}
|
1994-05-24 10:09:53 +00:00
|
|
|
if (*ndp->ni_next == '/') {
|
|
|
|
cnp->cn_nameptr = ndp->ni_next;
|
|
|
|
while (*cnp->cn_nameptr == '/') {
|
|
|
|
cnp->cn_nameptr++;
|
|
|
|
ndp->ni_pathlen--;
|
|
|
|
}
|
2005-04-09 11:53:16 +00:00
|
|
|
if (ndp->ni_dvp != dp)
|
|
|
|
vput(ndp->ni_dvp);
|
|
|
|
else
|
|
|
|
vrele(ndp->ni_dvp);
|
1994-05-24 10:09:53 +00:00
|
|
|
goto dirloop;
|
|
|
|
}
|
2009-05-29 10:02:44 +00:00
|
|
|
/*
|
|
|
|
* If we're processing a path with a trailing slash,
|
|
|
|
* check that the end result is a directory.
|
|
|
|
*/
|
|
|
|
if ((cnp->cn_flags & TRAILINGSLASH) && dp->v_type != VDIR) {
|
|
|
|
error = ENOTDIR;
|
|
|
|
goto bad2;
|
|
|
|
}
|
1994-05-24 10:09:53 +00:00
|
|
|
/*
|
2002-05-16 21:28:32 +00:00
|
|
|
* Disallow directory write attempts on read-only filesystems.
|
1994-05-24 10:09:53 +00:00
|
|
|
*/
|
1995-10-22 09:32:48 +00:00
|
|
|
if (rdonly &&
|
|
|
|
(cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
|
|
|
|
error = EROFS;
|
|
|
|
goto bad2;
|
1994-05-24 10:09:53 +00:00
|
|
|
}
|
2005-04-09 11:53:16 +00:00
|
|
|
if (!wantparent) {
|
2012-01-01 18:45:59 +00:00
|
|
|
ni_dvp_unlocked = 2;
|
2005-04-09 11:53:16 +00:00
|
|
|
if (ndp->ni_dvp != dp)
|
|
|
|
vput(ndp->ni_dvp);
|
|
|
|
else
|
|
|
|
vrele(ndp->ni_dvp);
|
2012-01-01 18:45:59 +00:00
|
|
|
} else if ((cnp->cn_flags & LOCKPARENT) == 0 && ndp->ni_dvp != dp) {
|
2020-01-03 22:29:58 +00:00
|
|
|
VOP_UNLOCK(ndp->ni_dvp);
|
2012-01-01 18:45:59 +00:00
|
|
|
ni_dvp_unlocked = 1;
|
|
|
|
}
|
1997-12-29 00:25:11 +00:00
|
|
|
|
2006-02-05 15:42:01 +00:00
|
|
|
if (cnp->cn_flags & AUDITVNODE1)
|
2009-07-28 21:52:24 +00:00
|
|
|
AUDIT_ARG_VNODE1(dp);
|
2006-02-05 15:42:01 +00:00
|
|
|
else if (cnp->cn_flags & AUDITVNODE2)
|
2009-07-28 21:52:24 +00:00
|
|
|
AUDIT_ARG_VNODE2(dp);
|
2006-02-05 15:42:01 +00:00
|
|
|
|
1994-05-24 10:09:53 +00:00
|
|
|
if ((cnp->cn_flags & LOCKLEAF) == 0)
|
2020-01-03 22:29:58 +00:00
|
|
|
VOP_UNLOCK(dp);
|
2005-01-24 10:27:05 +00:00
|
|
|
success:
|
2020-08-22 06:56:04 +00:00
|
|
|
/*
|
|
|
|
* FIXME: for lookups which only cross a mount point to fetch the
|
|
|
|
* root vnode, ni_dvp will be set to vp_crossmp. This can be a problem
|
|
|
|
* if either WANTPARENT or LOCKPARENT is set.
|
|
|
|
*/
|
2007-09-21 10:16:56 +00:00
|
|
|
/*
|
2018-09-20 18:25:26 +00:00
|
|
|
* Because of shared lookup we may have the vnode shared locked, but
|
2007-09-21 10:16:56 +00:00
|
|
|
* the caller may want it to be exclusively locked.
|
|
|
|
*/
|
2009-03-11 14:13:47 +00:00
|
|
|
if (needs_exclusive_leaf(dp->v_mount, cnp->cn_flags) &&
|
|
|
|
VOP_ISLOCKED(dp) != LK_EXCLUSIVE) {
|
2008-01-10 01:10:58 +00:00
|
|
|
vn_lock(dp, LK_UPGRADE | LK_RETRY);
|
2019-12-08 21:30:04 +00:00
|
|
|
if (VN_IS_DOOMED(dp)) {
|
2008-12-18 11:58:12 +00:00
|
|
|
error = ENOENT;
|
|
|
|
goto bad2;
|
|
|
|
}
|
2007-09-21 10:16:56 +00:00
|
|
|
}
|
2022-03-11 15:51:39 +00:00
|
|
|
success_right_lock:
|
2020-12-27 23:33:04 +00:00
|
|
|
if (ndp->ni_vp != NULL) {
|
2021-02-28 00:12:43 +00:00
|
|
|
if ((cnp->cn_flags & ISDOTDOT) == 0)
|
|
|
|
nameicap_tracker_add(ndp, ndp->ni_vp);
|
2020-12-27 23:33:04 +00:00
|
|
|
if ((cnp->cn_flags & (FAILIFEXISTS | ISSYMLINK)) == FAILIFEXISTS)
|
2022-03-13 17:36:51 +00:00
|
|
|
return (vfs_lookup_failifexists(ndp));
|
2020-12-27 23:33:04 +00:00
|
|
|
}
|
1994-05-24 10:09:53 +00:00
|
|
|
return (0);
|
|
|
|
|
|
|
|
bad2:
|
2012-01-01 18:45:59 +00:00
|
|
|
if (ni_dvp_unlocked != 2) {
|
|
|
|
if (dp != ndp->ni_dvp && !ni_dvp_unlocked)
|
|
|
|
vput(ndp->ni_dvp);
|
|
|
|
else
|
|
|
|
vrele(ndp->ni_dvp);
|
|
|
|
}
|
1994-05-24 10:09:53 +00:00
|
|
|
bad:
|
2023-07-05 21:52:07 +00:00
|
|
|
vput(dp);
|
2022-03-11 15:51:39 +00:00
|
|
|
bad_unlocked:
|
1994-05-24 10:09:53 +00:00
|
|
|
ndp->ni_vp = NULL;
|
|
|
|
return (error);
|
|
|
|
}
|
|
|
|
|
1994-09-27 20:33:41 +00:00
|
|
|
/*
|
|
|
|
* relookup - lookup a path name component
|
2007-05-27 20:50:23 +00:00
|
|
|
* Used by lookup to re-acquire things.
|
1994-09-27 20:33:41 +00:00
|
|
|
*/
|
|
|
|
int
|
2022-11-10 01:45:13 +00:00
|
|
|
vfs_relookup(struct vnode *dvp, struct vnode **vpp, struct componentname *cnp,
|
|
|
|
bool refstart)
|
1994-09-27 20:33:41 +00:00
|
|
|
{
|
2016-04-15 16:10:11 +00:00
|
|
|
struct vnode *dp = NULL; /* the directory we are searching */
|
1994-09-27 20:33:41 +00:00
|
|
|
int rdonly; /* lookup read-only flag bit */
|
|
|
|
int error = 0;
|
|
|
|
|
2005-03-28 09:24:50 +00:00
|
|
|
KASSERT(cnp->cn_flags & ISLASTCN,
|
|
|
|
("relookup: Not given last component."));
|
1994-09-27 20:33:41 +00:00
|
|
|
/*
|
|
|
|
* Setup: break out flag bits into variables.
|
|
|
|
*/
|
2020-11-23 12:47:23 +00:00
|
|
|
KASSERT((cnp->cn_flags & (LOCKPARENT | WANTPARENT)) != 0,
|
|
|
|
("relookup: parent not wanted"));
|
1994-09-27 20:33:41 +00:00
|
|
|
rdonly = cnp->cn_flags & RDONLY;
|
|
|
|
cnp->cn_flags &= ~ISSYMLINK;
|
|
|
|
dp = dvp;
|
2005-03-29 10:07:15 +00:00
|
|
|
cnp->cn_lkflags = LK_EXCLUSIVE;
|
2008-01-10 01:10:58 +00:00
|
|
|
vn_lock(dp, LK_EXCLUSIVE | LK_RETRY);
|
1994-09-27 20:33:41 +00:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Search a new directory.
|
|
|
|
*
|
2022-09-17 09:10:38 +00:00
|
|
|
* See a comment in vfs_lookup for cnp->cn_nameptr.
|
2023-08-09 10:37:13 +00:00
|
|
|
*
|
2010-03-26 11:33:12 +00:00
|
|
|
* Check for "" which represents the root directory after slash
|
|
|
|
* removal.
|
1994-09-27 20:33:41 +00:00
|
|
|
*/
|
|
|
|
if (cnp->cn_nameptr[0] == '\0') {
|
2010-03-26 11:33:12 +00:00
|
|
|
/*
|
|
|
|
* Support only LOOKUP for "/" because lookup()
|
|
|
|
* can't succeed for CREATE, DELETE and RENAME.
|
|
|
|
*/
|
|
|
|
KASSERT(cnp->cn_nameiop == LOOKUP, ("nameiop must be LOOKUP"));
|
|
|
|
KASSERT(dp->v_type == VDIR, ("dp is not a directory"));
|
|
|
|
|
1994-09-27 20:33:41 +00:00
|
|
|
if (!(cnp->cn_flags & LOCKLEAF))
|
2020-01-03 22:29:58 +00:00
|
|
|
VOP_UNLOCK(dp);
|
1994-09-27 20:33:41 +00:00
|
|
|
*vpp = dp;
|
1999-12-15 23:02:35 +00:00
|
|
|
/* XXX This should probably move to the top of function. */
|
2022-11-10 01:45:13 +00:00
|
|
|
if (refstart)
|
1994-09-27 20:33:41 +00:00
|
|
|
panic("lookup: SAVESTART");
|
|
|
|
return (0);
|
|
|
|
}
|
|
|
|
|
|
|
|
if (cnp->cn_flags & ISDOTDOT)
|
|
|
|
panic ("relookup: lookup on dot-dot");
|
1994-05-24 10:09:53 +00:00
|
|
|
|
1994-09-27 20:33:41 +00:00
|
|
|
/*
|
|
|
|
* We now have a segment name to search for, and a directory to search.
|
|
|
|
*/
|
1999-01-28 00:57:57 +00:00
|
|
|
if ((error = VOP_LOOKUP(dp, vpp, cnp)) != 0) {
|
1999-01-08 17:31:30 +00:00
|
|
|
KASSERT(*vpp == NULL, ("leaf should be empty"));
|
1994-09-27 20:33:41 +00:00
|
|
|
if (error != EJUSTRETURN)
|
|
|
|
goto bad;
|
|
|
|
/*
|
|
|
|
* If creating and at end of pathname, then can consider
|
|
|
|
* allowing file to be created.
|
|
|
|
*/
|
1995-10-22 09:32:48 +00:00
|
|
|
if (rdonly) {
|
1994-09-27 20:33:41 +00:00
|
|
|
error = EROFS;
|
|
|
|
goto bad;
|
|
|
|
}
|
|
|
|
/* ASSERT(dvp == ndp->ni_startdir) */
|
2022-11-10 01:45:13 +00:00
|
|
|
if (refstart)
|
1994-09-27 20:33:41 +00:00
|
|
|
VREF(dvp);
|
2005-03-28 09:24:50 +00:00
|
|
|
if ((cnp->cn_flags & LOCKPARENT) == 0)
|
2020-01-03 22:29:58 +00:00
|
|
|
VOP_UNLOCK(dp);
|
1994-09-27 20:33:41 +00:00
|
|
|
/*
|
|
|
|
* We return with ni_vp NULL to indicate that the entry
|
|
|
|
* doesn't currently exist, leaving a pointer to the
|
2006-08-05 21:08:47 +00:00
|
|
|
* (possibly locked) directory vnode in ndp->ni_dvp.
|
1994-09-27 20:33:41 +00:00
|
|
|
*/
|
|
|
|
return (0);
|
|
|
|
}
|
2006-09-13 18:39:09 +00:00
|
|
|
|
1994-09-27 20:33:41 +00:00
|
|
|
dp = *vpp;
|
|
|
|
|
|
|
|
/*
|
2002-05-16 21:28:32 +00:00
|
|
|
* Disallow directory write attempts on read-only filesystems.
|
1994-09-27 20:33:41 +00:00
|
|
|
*/
|
1995-10-22 09:32:48 +00:00
|
|
|
if (rdonly &&
|
|
|
|
(cnp->cn_nameiop == DELETE || cnp->cn_nameiop == RENAME)) {
|
2005-04-13 10:57:13 +00:00
|
|
|
if (dvp == dp)
|
|
|
|
vrele(dvp);
|
|
|
|
else
|
|
|
|
vput(dvp);
|
1995-10-22 09:32:48 +00:00
|
|
|
error = EROFS;
|
2005-04-13 10:57:13 +00:00
|
|
|
goto bad;
|
1994-09-27 20:33:41 +00:00
|
|
|
}
|
2005-04-13 10:57:13 +00:00
|
|
|
/*
|
|
|
|
* Set the parent lock/ref state to the requested state.
|
|
|
|
*/
|
2020-11-23 12:47:23 +00:00
|
|
|
if ((cnp->cn_flags & LOCKPARENT) == 0 && dvp != dp)
|
|
|
|
VOP_UNLOCK(dvp);
|
2005-04-13 10:57:13 +00:00
|
|
|
/*
|
|
|
|
* Check for symbolic link
|
|
|
|
*/
|
|
|
|
KASSERT(dp->v_type != VLNK || !(cnp->cn_flags & FOLLOW),
|
|
|
|
("relookup: symlink found.\n"));
|
|
|
|
|
1994-09-27 20:33:41 +00:00
|
|
|
/* ASSERT(dvp == ndp->ni_startdir) */
|
2022-11-10 01:45:13 +00:00
|
|
|
if (refstart)
|
1994-09-27 20:33:41 +00:00
|
|
|
VREF(dvp);
|
2020-07-10 09:01:36 +00:00
|
|
|
|
1994-09-27 20:33:41 +00:00
|
|
|
if ((cnp->cn_flags & LOCKLEAF) == 0)
|
2020-01-03 22:29:58 +00:00
|
|
|
VOP_UNLOCK(dp);
|
1994-09-27 20:33:41 +00:00
|
|
|
return (0);
|
|
|
|
bad:
|
|
|
|
vput(dp);
|
|
|
|
*vpp = NULL;
|
|
|
|
return (error);
|
|
|
|
}
|
2005-02-07 18:44:55 +00:00
|
|
|
|
2020-08-23 21:06:41 +00:00
|
|
|
#ifdef INVARIANTS
|
|
|
|
/*
|
|
|
|
* Validate the final state of ndp after the lookup.
|
|
|
|
*/
|
2022-09-12 22:49:47 +00:00
|
|
|
static void
|
2022-09-17 09:10:38 +00:00
|
|
|
NDVALIDATE_impl(struct nameidata *ndp, int line)
|
2020-08-23 21:06:41 +00:00
|
|
|
{
|
|
|
|
struct componentname *cnp;
|
|
|
|
|
|
|
|
cnp = &ndp->ni_cnd;
|
2022-09-17 09:10:38 +00:00
|
|
|
if (cnp->cn_pnbuf == NULL)
|
|
|
|
panic("%s: got no buf! called from %d", __func__, line);
|
2020-08-23 21:06:41 +00:00
|
|
|
}
|
2022-09-17 09:10:38 +00:00
|
|
|
|
2020-08-23 21:06:41 +00:00
|
|
|
#endif
|