1 /* $NetBSD: procfs_cmdline.c,v 1.27 2008/04/28 20:24:08 martin 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 * 20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 23 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 30 * POSSIBILITY OF SUCH DAMAGE. 31 */ 32 33 #include <sys/cdefs.h> 34 __KERNEL_RCSID(0, "$NetBSD: procfs_cmdline.c,v 1.27 2008/04/28 20:24:08 martin Exp $"); 35 36 #include <sys/param.h> 37 #include <sys/systm.h> 38 #include <sys/syslimits.h> 39 #include <sys/proc.h> 40 #include <sys/vnode.h> 41 #include <sys/exec.h> 42 #include <sys/malloc.h> 43 #include <miscfs/procfs/procfs.h> 44 45 #include <uvm/uvm_extern.h> 46 47 /* 48 * code for returning process's command line arguments 49 */ 50 int 51 procfs_docmdline( 52 struct lwp *curl, 53 struct proc *p, 54 struct pfsnode *pfs, 55 struct uio *uio 56 ) 57 { 58 struct ps_strings pss; 59 int count, error; 60 size_t i, len, xlen, upper_bound; 61 struct uio auio; 62 struct iovec aiov; 63 struct vmspace *vm; 64 vaddr_t argv; 65 char *arg; 66 67 /* Don't allow writing. */ 68 if (uio->uio_rw != UIO_READ) 69 return (EOPNOTSUPP); 70 71 /* 72 * Allocate a temporary buffer to hold the arguments. 73 */ 74 arg = malloc(PAGE_SIZE, M_TEMP, M_WAITOK); 75 76 /* 77 * Zombies don't have a stack, so we can't read their psstrings. 78 * System processes also don't have a user stack. This is what 79 * ps(1) would display. 80 */ 81 if (P_ZOMBIE(p) || (p->p_flag & PK_SYSTEM) != 0) { 82 len = snprintf(arg, PAGE_SIZE, "(%s)", p->p_comm) + 1; 83 error = uiomove_frombuf(arg, len, uio); 84 free(arg, M_TEMP); 85 return (error); 86 } 87 88 /* 89 * NOTE: Don't bother doing a process_checkioperm() here 90 * because the psstrings info is available by using ps(1), 91 * so it's not like there's anything to protect here. 92 */ 93 94 /* 95 * Lock the process down in memory. 96 */ 97 if ((error = proc_vmspace_getref(p, &vm)) != 0) { 98 free(arg, M_TEMP); 99 return (error); 100 } 101 102 /* 103 * Read in the ps_strings structure. 104 */ 105 aiov.iov_base = &pss; 106 aiov.iov_len = sizeof(pss); 107 auio.uio_iov = &aiov; 108 auio.uio_iovcnt = 1; 109 auio.uio_offset = (vaddr_t)p->p_psstr; 110 auio.uio_resid = sizeof(pss); 111 auio.uio_rw = UIO_READ; 112 UIO_SETUP_SYSSPACE(&auio); 113 error = uvm_io(&vm->vm_map, &auio); 114 if (error) 115 goto bad; 116 117 /* 118 * Now read the address of the argument vector. 119 */ 120 aiov.iov_base = &argv; 121 aiov.iov_len = sizeof(argv); 122 auio.uio_iov = &aiov; 123 auio.uio_iovcnt = 1; 124 auio.uio_offset = (vaddr_t)pss.ps_argvstr; 125 auio.uio_resid = sizeof(argv); 126 auio.uio_rw = UIO_READ; 127 UIO_SETUP_SYSSPACE(&auio); 128 error = uvm_io(&vm->vm_map, &auio); 129 if (error) 130 goto bad; 131 132 /* 133 * Now copy in the actual argument vector, one page at a time, 134 * since we don't know how long the vector is (though, we do 135 * know how many NUL-terminated strings are in the vector). 136 */ 137 len = 0; 138 count = pss.ps_nargvstr; 139 upper_bound = round_page(uio->uio_offset + uio->uio_resid); 140 for (; count && len < upper_bound; len += xlen) { 141 aiov.iov_base = arg; 142 aiov.iov_len = PAGE_SIZE; 143 auio.uio_iov = &aiov; 144 auio.uio_iovcnt = 1; 145 auio.uio_offset = argv + len; 146 xlen = PAGE_SIZE - ((argv + len) & PAGE_MASK); 147 auio.uio_resid = xlen; 148 auio.uio_rw = UIO_READ; 149 UIO_SETUP_SYSSPACE(&auio); 150 error = uvm_io(&vm->vm_map, &auio); 151 if (error) 152 goto bad; 153 154 for (i = 0; i < xlen && count != 0; i++) { 155 if (arg[i] == '\0') 156 count--; /* one full string */ 157 } 158 159 if (len + i > uio->uio_offset) { 160 /* Have data in this page, copy it out */ 161 error = uiomove(arg + uio->uio_offset - len, 162 i + len - uio->uio_offset, uio); 163 if (error || uio->uio_resid <= 0) 164 break; 165 } 166 } 167 168 bad: 169 /* 170 * Release the process. 171 */ 172 uvmspace_free(vm); 173 174 free(arg, M_TEMP); 175 return (error); 176 } 177