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 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