1 /* $NetBSD: procfs_cmdline.c,v 1.33 2024/05/18 00:05:50 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 * 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 1.33 2024/05/18 00:05:50 thorpej 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/sysctl.h> 43 #include <miscfs/procfs/procfs.h> 44 45 #include <uvm/uvm_extern.h> 46 47 static int 48 procfs_doprocargs_helper(void *cookie, const void *src, size_t off, size_t len) 49 { 50 struct uio *uio = cookie; 51 char *buf = __UNCONST(src); 52 53 buf += uio->uio_offset - off; 54 if (off + len <= (uintmax_t)uio->uio_offset) 55 return 0; 56 return uiomove(buf, off + len - uio->uio_offset, cookie); 57 } 58 59 /* 60 * code for returning process's command line arguments/environment 61 */ 62 int 63 procfs_doprocargs( 64 struct lwp *curl, 65 struct proc *p, 66 struct pfsnode *pfs, 67 struct uio *uio, 68 int oid 69 ) 70 { 71 size_t len, start; 72 int error; 73 74 /* Don't allow writing. */ 75 if (uio->uio_rw != UIO_READ) 76 return EOPNOTSUPP; 77 78 /* 79 * Zombies don't have a stack, so we can't read their psstrings. 80 * System processes also don't have a user stack. This is what 81 * ps(1) would display. 82 */ 83 if (P_ZOMBIE(p) || (p->p_flag & PK_SYSTEM) != 0) { 84 static char msg[] = "()"; 85 error = 0; 86 if (0 == uio->uio_offset) { 87 error = uiomove(msg, 1, uio); 88 if (error) 89 return error; 90 } 91 len = strlen(p->p_comm); 92 if (len >= (uintmax_t)uio->uio_offset) { 93 start = uio->uio_offset - 1; 94 error = uiomove(p->p_comm + start, len - start, uio); 95 if (error) 96 return error; 97 } 98 if (len + 2 >= (uintmax_t)uio->uio_offset) { 99 start = uio->uio_offset - 1 - len; 100 error = uiomove(msg + 1 + start, 2 - start, uio); 101 } 102 return error; 103 } 104 105 len = uio->uio_offset + uio->uio_resid; 106 return copy_procargs(p, oid, &len, procfs_doprocargs_helper, uio); 107 } 108