1 /* $NetBSD: procfs_cmdline.c,v 1.5 1999/04/27 06:02:09 thorpej 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, count, error, i; 66 size_t len, upper_bound; 67 struct uio auio; 68 struct iovec aiov; 69 vaddr_t argv; 70 char *arg; 71 72 /* Don't allow writing. */ 73 if (uio->uio_rw != UIO_READ) 74 return (EOPNOTSUPP); 75 76 /* 77 * Allocate a temporary buffer to hold the arguments. 78 */ 79 arg = malloc(PAGE_SIZE, M_TEMP, M_WAITOK); 80 81 /* 82 * Zombies don't have a stack, so we can't read their psstrings. 83 * System processes also don't have a user stack. This is what 84 * ps(1) would display. 85 */ 86 if (p->p_stat == SZOMB || (p->p_flag & P_SYSTEM) != 0) { 87 len = snprintf(arg, PAGE_SIZE, "(%s)", p->p_comm); 88 goto doio; 89 } 90 91 /* 92 * NOTE: Don't bother doing a procfs_checkioperm() here 93 * because the psstrings info is available by using ps(1), 94 * so it's not like there's anything to protect here. 95 */ 96 97 /* 98 * Lock the process down in memory. 99 */ 100 /* XXXCDC: how should locking work here? */ 101 if ((p->p_flag & P_WEXIT) || (p->p_vmspace->vm_refcnt < 1)) 102 return (EFAULT); 103 PHOLD(p); 104 p->p_vmspace->vm_refcnt++; /* XXX */ 105 106 /* 107 * Read in the ps_strings structure. 108 */ 109 aiov.iov_base = &pss; 110 aiov.iov_len = sizeof(pss); 111 auio.uio_iov = &aiov; 112 auio.uio_iovcnt = 1; 113 auio.uio_offset = (vaddr_t)PS_STRINGS; 114 auio.uio_resid = sizeof(pss); 115 auio.uio_segflg = UIO_SYSSPACE; 116 auio.uio_rw = UIO_READ; 117 auio.uio_procp = NULL; 118 error = uvm_io(&p->p_vmspace->vm_map, &auio); 119 if (error) 120 goto bad; 121 122 /* 123 * Now read the address of the argument vector. 124 */ 125 aiov.iov_base = &argv; 126 aiov.iov_len = sizeof(argv); 127 auio.uio_iov = &aiov; 128 auio.uio_iovcnt = 1; 129 auio.uio_offset = (vaddr_t)pss.ps_argvstr; 130 auio.uio_resid = sizeof(argv); 131 auio.uio_segflg = UIO_SYSSPACE; 132 auio.uio_rw = UIO_READ; 133 auio.uio_procp = NULL; 134 error = uvm_io(&p->p_vmspace->vm_map, &auio); 135 if (error) 136 goto bad; 137 138 /* 139 * Now copy in the actual argument vector, one page at a time, 140 * since we don't know how long the vector is (though, we do 141 * know how many NUL-terminated strings are in the vector). 142 */ 143 len = 0; 144 count = pss.ps_nargvstr; 145 upper_bound = round_page(uio->uio_offset + 1); 146 for (; count && len < upper_bound; len += PAGE_SIZE) { 147 aiov.iov_base = arg; 148 aiov.iov_len = PAGE_SIZE; 149 auio.uio_iov = &aiov; 150 auio.uio_iovcnt = 1; 151 auio.uio_offset = argv + len; 152 auio.uio_resid = PAGE_SIZE; 153 auio.uio_segflg = UIO_SYSSPACE; 154 auio.uio_rw = UIO_READ; 155 auio.uio_procp = NULL; 156 error = uvm_io(&p->p_vmspace->vm_map, &auio); 157 if (error) 158 goto bad; 159 160 for (i = len; i < (len + PAGE_SIZE) && count != 0; i++) { 161 if (arg[i] == '\0') 162 count--; /* one full string */ 163 } 164 165 if (count == 0) { 166 /* No more argv strings, set up len and break. */ 167 len = i; 168 break; 169 } 170 } 171 if (len > 0) 172 len--; /* exclude last NUL */ 173 174 /* 175 * Release the process. 176 */ 177 PRELE(p); 178 uvmspace_free(p->p_vmspace); 179 180 doio: 181 xlen = len - uio->uio_offset; 182 if (xlen <= 0) 183 error = 0; 184 else 185 error = uiomove(arg + trunc_page(len), xlen, uio); 186 187 free(arg, M_TEMP); 188 return (error); 189 190 bad: 191 PRELE(p); 192 uvmspace_free(p->p_vmspace); 193 free(arg, M_TEMP); 194 return (error); 195 } 196