1 /* $NetBSD: procfs_cmdline.c,v 1.12 2001/11/10 13:33:43 lukem 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/cdefs.h> 41 __KERNEL_RCSID(0, "$NetBSD: procfs_cmdline.c,v 1.12 2001/11/10 13:33:43 lukem Exp $"); 42 43 #include <sys/param.h> 44 #include <sys/types.h> 45 #include <sys/systm.h> 46 #include <sys/syslimits.h> 47 #include <sys/proc.h> 48 #include <sys/vnode.h> 49 #include <sys/exec.h> 50 #include <sys/malloc.h> 51 #include <miscfs/procfs/procfs.h> 52 53 #include <uvm/uvm_extern.h> 54 55 /* 56 * code for returning process's command line arguments 57 */ 58 int 59 procfs_docmdline(curp, p, pfs, uio) 60 struct proc *curp; 61 struct proc *p; 62 struct pfsnode *pfs; 63 struct uio *uio; 64 { 65 struct ps_strings pss; 66 int count, error, i; 67 size_t len, xlen, upper_bound; 68 struct uio auio; 69 struct iovec aiov; 70 vaddr_t argv; 71 char *arg; 72 73 /* Don't allow writing. */ 74 if (uio->uio_rw != UIO_READ) 75 return (EOPNOTSUPP); 76 77 /* 78 * Allocate a temporary buffer to hold the arguments. 79 */ 80 arg = malloc(PAGE_SIZE, M_TEMP, M_WAITOK); 81 82 /* 83 * Zombies don't have a stack, so we can't read their psstrings. 84 * System processes also don't have a user stack. This is what 85 * ps(1) would display. 86 */ 87 if (P_ZOMBIE(p) || (p->p_flag & P_SYSTEM) != 0) { 88 len = snprintf(arg, PAGE_SIZE, "(%s)", p->p_comm); 89 xlen = len - uio->uio_offset; 90 if (xlen <= 0) 91 error = 0; 92 else 93 error = uiomove(arg, xlen, uio); 94 95 free(arg, M_TEMP); 96 return (error); 97 } 98 99 /* 100 * NOTE: Don't bother doing a procfs_checkioperm() here 101 * because the psstrings info is available by using ps(1), 102 * so it's not like there's anything to protect here. 103 */ 104 105 /* 106 * Lock the process down in memory. 107 */ 108 /* XXXCDC: how should locking work here? */ 109 if ((p->p_flag & P_WEXIT) || (p->p_vmspace->vm_refcnt < 1)) { 110 free(arg, M_TEMP); 111 return (EFAULT); 112 } 113 p->p_vmspace->vm_refcnt++; /* XXX */ 114 115 /* 116 * Read in the ps_strings structure. 117 */ 118 aiov.iov_base = &pss; 119 aiov.iov_len = sizeof(pss); 120 auio.uio_iov = &aiov; 121 auio.uio_iovcnt = 1; 122 auio.uio_offset = (vaddr_t)p->p_psstr; 123 auio.uio_resid = sizeof(pss); 124 auio.uio_segflg = UIO_SYSSPACE; 125 auio.uio_rw = UIO_READ; 126 auio.uio_procp = NULL; 127 error = uvm_io(&p->p_vmspace->vm_map, &auio); 128 if (error) 129 goto bad; 130 131 /* 132 * Now read the address of the argument vector. 133 */ 134 aiov.iov_base = &argv; 135 aiov.iov_len = sizeof(argv); 136 auio.uio_iov = &aiov; 137 auio.uio_iovcnt = 1; 138 auio.uio_offset = (vaddr_t)pss.ps_argvstr; 139 auio.uio_resid = sizeof(argv); 140 auio.uio_segflg = UIO_SYSSPACE; 141 auio.uio_rw = UIO_READ; 142 auio.uio_procp = NULL; 143 error = uvm_io(&p->p_vmspace->vm_map, &auio); 144 if (error) 145 goto bad; 146 147 /* 148 * Now copy in the actual argument vector, one page at a time, 149 * since we don't know how long the vector is (though, we do 150 * know how many NUL-terminated strings are in the vector). 151 */ 152 len = 0; 153 count = pss.ps_nargvstr; 154 upper_bound = round_page(uio->uio_offset + uio->uio_resid); 155 for (; count && len < upper_bound; len += xlen) { 156 aiov.iov_base = arg; 157 aiov.iov_len = PAGE_SIZE; 158 auio.uio_iov = &aiov; 159 auio.uio_iovcnt = 1; 160 auio.uio_offset = argv + len; 161 xlen = PAGE_SIZE - ((argv + len) & PAGE_MASK); 162 auio.uio_resid = xlen; 163 auio.uio_segflg = UIO_SYSSPACE; 164 auio.uio_rw = UIO_READ; 165 auio.uio_procp = NULL; 166 error = uvm_io(&p->p_vmspace->vm_map, &auio); 167 if (error) 168 goto bad; 169 170 for (i = 0; i < xlen && count != 0; i++) { 171 if (arg[i] == '\0') 172 count--; /* one full string */ 173 } 174 175 if (count == 0) 176 i--; /* exclude the final NUL */ 177 178 if (len + i > uio->uio_offset) { 179 /* Have data in this page, copy it out */ 180 error = uiomove(arg + uio->uio_offset - len, 181 i + len - uio->uio_offset, uio); 182 if (error || uio->uio_resid <= 0) 183 break; 184 } 185 } 186 187 bad: 188 /* 189 * Release the process. 190 */ 191 uvmspace_free(p->p_vmspace); 192 193 free(arg, M_TEMP); 194 return (error); 195 } 196