1 /* $NetBSD: kern_ktrace_vfs.c,v 1.3 2021/06/29 22:40:53 dholland Exp $ */
2
3 /*-
4 * Copyright (c) 2006, 2007, 2008 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Andrew Doran.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in the
17 * documentation and/or other materials provided with the distribution.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 /*
33 * Copyright (c) 1989, 1993
34 * The Regents of the University of California. All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 * notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 * notice, this list of conditions and the following disclaimer in the
43 * documentation and/or other materials provided with the distribution.
44 * 3. Neither the name of the University nor the names of its contributors
45 * may be used to endorse or promote products derived from this software
46 * without specific prior written permission.
47 *
48 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58 * SUCH DAMAGE.
59 *
60 * @(#)kern_ktrace.c 8.5 (Berkeley) 5/14/95
61 */
62
63 #include <sys/cdefs.h>
64 __KERNEL_RCSID(0, "$NetBSD: kern_ktrace_vfs.c,v 1.3 2021/06/29 22:40:53 dholland Exp $");
65
66 #include <sys/param.h>
67 #include <sys/systm.h>
68 #include <sys/file.h>
69 #include <sys/filedesc.h>
70 #include <sys/namei.h>
71 #include <sys/vnode.h>
72 #include <sys/kernel.h>
73 #include <sys/ktrace.h>
74 #include <sys/kauth.h>
75
76 #include <sys/mount.h>
77 #include <sys/syscallargs.h>
78
79 /*
80 * ktrace system call, the part of the ktrace framework that
81 * explicitly interacts with VFS
82 */
83 /* ARGSUSED */
84 int
sys_ktrace(struct lwp * l,const struct sys_ktrace_args * uap,register_t * retval)85 sys_ktrace(struct lwp *l, const struct sys_ktrace_args *uap, register_t *retval)
86 {
87 /* {
88 syscallarg(const char *) fname;
89 syscallarg(int) ops;
90 syscallarg(int) facs;
91 syscallarg(int) pid;
92 } */
93 struct vnode *vp = NULL;
94 file_t *fp = NULL;
95 struct pathbuf *pb;
96 int error = 0;
97 int fd;
98
99 if (ktrenter(l))
100 return EAGAIN;
101
102 if (KTROP(SCARG(uap, ops)) != KTROP_CLEAR) {
103 /*
104 * an operation which requires a file argument.
105 */
106 error = pathbuf_copyin(SCARG(uap, fname), &pb);
107 if (error) {
108 ktrexit(l);
109 return (error);
110 }
111 error = vn_open(NULL, pb, 0, FREAD|FWRITE, 0, &vp, NULL, NULL);
112 if (error != 0) {
113 pathbuf_destroy(pb);
114 ktrexit(l);
115 return (error);
116 }
117 pathbuf_destroy(pb);
118 VOP_UNLOCK(vp);
119 if (vp->v_type != VREG) {
120 vn_close(vp, FREAD|FWRITE, l->l_cred);
121 ktrexit(l);
122 return (EACCES);
123 }
124 /*
125 * This uses up a file descriptor slot in the
126 * tracing process for the duration of this syscall.
127 * This is not expected to be a problem.
128 */
129 if ((error = fd_allocfile(&fp, &fd)) != 0) {
130 vn_close(vp, FWRITE, l->l_cred);
131 ktrexit(l);
132 return error;
133 }
134 fp->f_flag = FWRITE;
135 fp->f_type = DTYPE_VNODE;
136 fp->f_ops = &vnops;
137 fp->f_vnode = vp;
138 vp = NULL;
139 }
140 error = ktrace_common(l, SCARG(uap, ops), SCARG(uap, facs),
141 SCARG(uap, pid), &fp);
142 if (KTROP(SCARG(uap, ops)) != KTROP_CLEAR)
143 fd_abort(curproc, fp, fd);
144 return (error);
145 }
146