1 /* $NetBSD: procfs_cmdline.c,v 1.24 2006/12/28 09:17:52 elad 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 1.24 2006/12/28 09:17:52 elad Exp $"); 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/syslimits.h> 46 #include <sys/proc.h> 47 #include <sys/vnode.h> 48 #include <sys/exec.h> 49 #include <sys/malloc.h> 50 #include <miscfs/procfs/procfs.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( 59 struct lwp *curl, 60 struct proc *p, 61 struct pfsnode *pfs, 62 struct uio *uio 63 ) 64 { 65 struct ps_strings pss; 66 int count, error; 67 size_t i, 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) + 1; 89 error = uiomove_frombuf(arg, len, uio); 90 91 free(arg, M_TEMP); 92 return (error); 93 } 94 95 /* 96 * NOTE: Don't bother doing a process_checkioperm() here 97 * because the psstrings info is available by using ps(1), 98 * so it's not like there's anything to protect here. 99 */ 100 101 /* 102 * Lock the process down in memory. 103 */ 104 /* XXXCDC: how should locking work here? */ 105 if ((p->p_flag & P_WEXIT) || (p->p_vmspace->vm_refcnt < 1)) { 106 free(arg, M_TEMP); 107 return (EFAULT); 108 } 109 p->p_vmspace->vm_refcnt++; /* XXX */ 110 111 /* 112 * Read in the ps_strings structure. 113 */ 114 aiov.iov_base = &pss; 115 aiov.iov_len = sizeof(pss); 116 auio.uio_iov = &aiov; 117 auio.uio_iovcnt = 1; 118 auio.uio_offset = (vaddr_t)p->p_psstr; 119 auio.uio_resid = sizeof(pss); 120 auio.uio_rw = UIO_READ; 121 UIO_SETUP_SYSSPACE(&auio); 122 error = uvm_io(&p->p_vmspace->vm_map, &auio); 123 if (error) 124 goto bad; 125 126 /* 127 * Now read the address of the argument vector. 128 */ 129 aiov.iov_base = &argv; 130 aiov.iov_len = sizeof(argv); 131 auio.uio_iov = &aiov; 132 auio.uio_iovcnt = 1; 133 auio.uio_offset = (vaddr_t)pss.ps_argvstr; 134 auio.uio_resid = sizeof(argv); 135 auio.uio_rw = UIO_READ; 136 UIO_SETUP_SYSSPACE(&auio); 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 page 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 upper_bound = round_page(uio->uio_offset + uio->uio_resid); 149 for (; count && len < upper_bound; len += xlen) { 150 aiov.iov_base = arg; 151 aiov.iov_len = PAGE_SIZE; 152 auio.uio_iov = &aiov; 153 auio.uio_iovcnt = 1; 154 auio.uio_offset = argv + len; 155 xlen = PAGE_SIZE - ((argv + len) & PAGE_MASK); 156 auio.uio_resid = xlen; 157 auio.uio_rw = UIO_READ; 158 UIO_SETUP_SYSSPACE(&auio); 159 error = uvm_io(&p->p_vmspace->vm_map, &auio); 160 if (error) 161 goto bad; 162 163 for (i = 0; i < xlen && count != 0; i++) { 164 if (arg[i] == '\0') 165 count--; /* one full string */ 166 } 167 168 if (len + i > uio->uio_offset) { 169 /* Have data in this page, copy it out */ 170 error = uiomove(arg + uio->uio_offset - len, 171 i + len - uio->uio_offset, uio); 172 if (error || uio->uio_resid <= 0) 173 break; 174 } 175 } 176 177 bad: 178 /* 179 * Release the process. 180 */ 181 uvmspace_free(p->p_vmspace); 182 183 free(arg, M_TEMP); 184 return (error); 185 } 186