1 /* $NetBSD: procfs_cmdline.c,v 1.20 2005/12/11 12:24:51 christos 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 1.20 2005/12/11 12:24:51 christos 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(curl, p, pfs, uio) 59 struct lwp *curl; 60 struct proc *p; 61 struct pfsnode *pfs; 62 struct uio *uio; 63 { 64 struct ps_strings pss; 65 int count, error; 66 size_t i, len, xlen, 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_ZOMBIE(p) || (p->p_flag & P_SYSTEM) != 0) { 87 len = snprintf(arg, PAGE_SIZE, "(%s)", p->p_comm); 88 error = uiomove_frombuf(arg, len, uio); 89 90 free(arg, M_TEMP); 91 return (error); 92 } 93 94 /* 95 * NOTE: Don't bother doing a process_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 free(arg, M_TEMP); 106 return (EFAULT); 107 } 108 p->p_vmspace->vm_refcnt++; /* XXX */ 109 110 /* 111 * Read in the ps_strings structure. 112 */ 113 aiov.iov_base = &pss; 114 aiov.iov_len = sizeof(pss); 115 auio.uio_iov = &aiov; 116 auio.uio_iovcnt = 1; 117 auio.uio_offset = (vaddr_t)p->p_psstr; 118 auio.uio_resid = sizeof(pss); 119 auio.uio_segflg = UIO_SYSSPACE; 120 auio.uio_rw = UIO_READ; 121 auio.uio_lwp = NULL; 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_segflg = UIO_SYSSPACE; 136 auio.uio_rw = UIO_READ; 137 auio.uio_lwp = NULL; 138 error = uvm_io(&p->p_vmspace->vm_map, &auio); 139 if (error) 140 goto bad; 141 142 /* 143 * Now copy in the actual argument vector, one page at a time, 144 * since we don't know how long the vector is (though, we do 145 * know how many NUL-terminated strings are in the vector). 146 */ 147 len = 0; 148 count = pss.ps_nargvstr; 149 upper_bound = round_page(uio->uio_offset + uio->uio_resid); 150 for (; count && len < upper_bound; len += xlen) { 151 aiov.iov_base = arg; 152 aiov.iov_len = PAGE_SIZE; 153 auio.uio_iov = &aiov; 154 auio.uio_iovcnt = 1; 155 auio.uio_offset = argv + len; 156 xlen = PAGE_SIZE - ((argv + len) & PAGE_MASK); 157 auio.uio_resid = xlen; 158 auio.uio_segflg = UIO_SYSSPACE; 159 auio.uio_rw = UIO_READ; 160 auio.uio_lwp = NULL; 161 error = uvm_io(&p->p_vmspace->vm_map, &auio); 162 if (error) 163 goto bad; 164 165 for (i = 0; i < xlen && count != 0; i++) { 166 if (arg[i] == '\0') 167 count--; /* one full string */ 168 } 169 170 if (count == 0) 171 i--; /* exclude the final NUL */ 172 173 if (len + i > uio->uio_offset) { 174 /* Have data in this page, copy it out */ 175 error = uiomove(arg + uio->uio_offset - len, 176 i + len - uio->uio_offset, uio); 177 if (error || uio->uio_resid <= 0) 178 break; 179 } 180 } 181 182 bad: 183 /* 184 * Release the process. 185 */ 186 uvmspace_free(p->p_vmspace); 187 188 free(arg, M_TEMP); 189 return (error); 190 } 191