1 /* $NetBSD: procfs_cmdline.c,v 1.4 1999/03/24 05:51:27 mrg Exp $ */ 2 3 /* 4 * Copyright (c) 1999 Jaromir Dolecek <dolecek@ics.muni.cz> 5 * Copyright (c) 1999 The NetBSD Foundation, Inc. 6 * All rights reserved. 7 * 8 * This code is derived from software contributed to The NetBSD Foundation 9 * by Jaromir Dolecek. 10 * 11 * Redistribution and use in source and binary forms, with or without 12 * modification, are permitted provided that the following conditions 13 * are met: 14 * 1. Redistributions of source code must retain the above copyright 15 * notice, this list of conditions and the following disclaimer. 16 * 2. Redistributions in binary form must reproduce the above copyright 17 * notice, this list of conditions and the following disclaimer in the 18 * documentation and/or other materials provided with the distribution. 19 * 3. All advertising materials mentioning features or use of this software 20 * must display the following acknowledgement: 21 * This product includes software developed by the NetBSD 22 * Foundation, Inc. and its contributors. 23 * 4. Neither the name of The NetBSD Foundation nor the names of its 24 * contributors may be used to endorse or promote products derived 25 * from this software without specific prior written permission. 26 * 27 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 28 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 29 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 30 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 31 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 32 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 33 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 34 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 35 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 36 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 37 * POSSIBILITY OF SUCH DAMAGE. 38 */ 39 40 #include <sys/param.h> 41 #include <sys/types.h> 42 #include <sys/systm.h> 43 #include <sys/syslimits.h> 44 #include <sys/proc.h> 45 #include <sys/vnode.h> 46 #include <sys/exec.h> 47 #include <sys/malloc.h> 48 #include <miscfs/procfs/procfs.h> 49 50 #include <vm/vm.h> 51 52 #include <uvm/uvm_extern.h> 53 54 /* 55 * code for returning process's command line arguments 56 */ 57 int 58 procfs_docmdline(curp, p, pfs, uio) 59 struct proc *curp; 60 struct proc *p; 61 struct pfsnode *pfs; 62 struct uio *uio; 63 { 64 struct ps_strings pss; 65 int xlen, len, count, error; 66 struct uio auio; 67 struct iovec aiov; 68 vaddr_t argv; 69 char *arg; 70 71 /* Don't allow writing. */ 72 if (uio->uio_rw != UIO_READ) 73 return (EOPNOTSUPP); 74 75 /* 76 * Allocate a temporary buffer to hold the arguments. 77 * 78 * XXX THIS COULD BE HANDLED MUCH MORE INTELLIGENTLY, 79 * XXX WITHOUT REQUIRING A 256k TEMPORARY BUFFER! 80 */ 81 arg = malloc(ARG_MAX, M_TEMP, M_WAITOK); 82 83 /* 84 * Zombies don't have a stack, so we can't read their psstrings. 85 * System processes also don't have a user stack. This is what 86 * ps(1) would display. 87 */ 88 if (p->p_stat == SZOMB || (p->p_flag & P_SYSTEM) != 0) { 89 snprintf(arg, sizeof(arg), "(%s)", p->p_comm); 90 len = strlen(arg); /* exclude last NUL */ 91 goto doio; 92 } 93 94 /* 95 * NOTE: Don't bother doing a procfs_checkioperm() here 96 * because the psstrings info is available by using ps(1), 97 * so it's not like there's anything to protect here. 98 */ 99 100 /* 101 * Lock the process down in memory. 102 */ 103 /* XXXCDC: how should locking work here? */ 104 if ((p->p_flag & P_WEXIT) || (p->p_vmspace->vm_refcnt < 1)) 105 return (EFAULT); 106 PHOLD(p); 107 p->p_vmspace->vm_refcnt++; /* XXX */ 108 109 /* 110 * Read in the ps_strings structure. 111 */ 112 aiov.iov_base = &pss; 113 aiov.iov_len = sizeof(pss); 114 auio.uio_iov = &aiov; 115 auio.uio_iovcnt = 1; 116 auio.uio_offset = (vaddr_t)PS_STRINGS; 117 auio.uio_resid = sizeof(pss); 118 auio.uio_segflg = UIO_SYSSPACE; 119 auio.uio_rw = UIO_READ; 120 auio.uio_procp = NULL; 121 error = uvm_io(&p->p_vmspace->vm_map, &auio); 122 if (error) 123 goto bad; 124 125 /* 126 * Now read the address of the argument vector. 127 */ 128 aiov.iov_base = &argv; 129 aiov.iov_len = sizeof(argv); 130 auio.uio_iov = &aiov; 131 auio.uio_iovcnt = 1; 132 auio.uio_offset = (vaddr_t)pss.ps_argvstr; 133 auio.uio_resid = sizeof(argv); 134 auio.uio_segflg = UIO_SYSSPACE; 135 auio.uio_rw = UIO_READ; 136 auio.uio_procp = NULL; 137 error = uvm_io(&p->p_vmspace->vm_map, &auio); 138 if (error) 139 goto bad; 140 141 /* 142 * Now copy in the actual argument vector, one byte at a time, 143 * since we don't know how long the vector is (though, we do 144 * know how many NUL-terminated strings are in the vector). 145 */ 146 len = 0; 147 count = pss.ps_nargvstr; 148 while (count && len < ARG_MAX) { 149 aiov.iov_base = &arg[len]; 150 aiov.iov_len = 1; 151 auio.uio_iov = &aiov; 152 auio.uio_iovcnt = 1; 153 auio.uio_offset = argv + len; 154 auio.uio_resid = 1; 155 auio.uio_segflg = UIO_SYSSPACE; 156 auio.uio_rw = UIO_READ; 157 auio.uio_procp = NULL; 158 error = uvm_io(&p->p_vmspace->vm_map, &auio); 159 if (error) 160 goto bad; 161 162 if (len > 0 && arg[len] == '\0') 163 count--; /* one full string */ 164 len++; 165 } 166 if (len > 0) 167 len--; /* exclude last NUL */ 168 169 /* 170 * Release the process. 171 */ 172 PRELE(p); 173 uvmspace_free(p->p_vmspace); 174 175 doio: 176 xlen = len - uio->uio_offset; 177 xlen = imin(xlen, uio->uio_resid); 178 if (xlen <= 0) 179 error = 0; 180 else 181 error = uiomove(arg + uio->uio_offset, xlen, uio); 182 183 free(arg, M_TEMP); 184 return (error); 185 186 bad: 187 PRELE(p); 188 uvmspace_free(p->p_vmspace); 189 free(arg, M_TEMP); 190 return (error); 191 } 192