1cdff2642SJohn Johansen /* 2cdff2642SJohn Johansen * AppArmor security module 3cdff2642SJohn Johansen * 4cdff2642SJohn Johansen * This file contains basic common functions used in AppArmor 5cdff2642SJohn Johansen * 6cdff2642SJohn Johansen * Copyright (C) 1998-2008 Novell/SUSE 7cdff2642SJohn Johansen * Copyright 2009-2010 Canonical Ltd. 8cdff2642SJohn Johansen * 9cdff2642SJohn Johansen * This program is free software; you can redistribute it and/or 10cdff2642SJohn Johansen * modify it under the terms of the GNU General Public License as 11cdff2642SJohn Johansen * published by the Free Software Foundation, version 2 of the 12cdff2642SJohn Johansen * License. 13cdff2642SJohn Johansen */ 14cdff2642SJohn Johansen 15b7f080cfSAlexey Dobriyan #include <linux/mm.h> 16cdff2642SJohn Johansen #include <linux/slab.h> 17cdff2642SJohn Johansen #include <linux/string.h> 18cdff2642SJohn Johansen #include <linux/vmalloc.h> 19cdff2642SJohn Johansen 20cdff2642SJohn Johansen #include "include/audit.h" 2132c3df63SJames Morris #include "include/apparmor.h" 22cdff2642SJohn Johansen 23cdff2642SJohn Johansen 24cdff2642SJohn Johansen /** 25cdff2642SJohn Johansen * aa_split_fqname - split a fqname into a profile and namespace name 26cdff2642SJohn Johansen * @fqname: a full qualified name in namespace profile format (NOT NULL) 27cdff2642SJohn Johansen * @ns_name: pointer to portion of the string containing the ns name (NOT NULL) 28cdff2642SJohn Johansen * 29cdff2642SJohn Johansen * Returns: profile name or NULL if one is not specified 30cdff2642SJohn Johansen * 31cdff2642SJohn Johansen * Split a namespace name from a profile name (see policy.c for naming 32cdff2642SJohn Johansen * description). If a portion of the name is missing it returns NULL for 33cdff2642SJohn Johansen * that portion. 34cdff2642SJohn Johansen * 35cdff2642SJohn Johansen * NOTE: may modify the @fqname string. The pointers returned point 36cdff2642SJohn Johansen * into the @fqname string. 37cdff2642SJohn Johansen */ 38cdff2642SJohn Johansen char *aa_split_fqname(char *fqname, char **ns_name) 39cdff2642SJohn Johansen { 40cdff2642SJohn Johansen char *name = strim(fqname); 41cdff2642SJohn Johansen 42cdff2642SJohn Johansen *ns_name = NULL; 43cdff2642SJohn Johansen if (name[0] == ':') { 44cdff2642SJohn Johansen char *split = strchr(&name[1], ':'); 4504ccd53fSJohn Johansen *ns_name = skip_spaces(&name[1]); 46cdff2642SJohn Johansen if (split) { 47cdff2642SJohn Johansen /* overwrite ':' with \0 */ 48cdff2642SJohn Johansen *split = 0; 49cdff2642SJohn Johansen name = skip_spaces(split + 1); 50cdff2642SJohn Johansen } else 51cdff2642SJohn Johansen /* a ns name without a following profile is allowed */ 52cdff2642SJohn Johansen name = NULL; 53cdff2642SJohn Johansen } 54cdff2642SJohn Johansen if (name && *name == 0) 55cdff2642SJohn Johansen name = NULL; 56cdff2642SJohn Johansen 57cdff2642SJohn Johansen return name; 58cdff2642SJohn Johansen } 59cdff2642SJohn Johansen 60cdff2642SJohn Johansen /** 61cdff2642SJohn Johansen * aa_info_message - log a none profile related status message 62cdff2642SJohn Johansen * @str: message to log 63cdff2642SJohn Johansen */ 64cdff2642SJohn Johansen void aa_info_message(const char *str) 65cdff2642SJohn Johansen { 66cdff2642SJohn Johansen if (audit_enabled) { 67cdff2642SJohn Johansen struct common_audit_data sa; 683b3b0e4fSEric Paris struct apparmor_audit_data aad = {0,}; 6950c205f5SEric Paris sa.type = LSM_AUDIT_DATA_NONE; 703b3b0e4fSEric Paris sa.aad = &aad; 713b3b0e4fSEric Paris aad.info = str; 72cdff2642SJohn Johansen aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, NULL); 73cdff2642SJohn Johansen } 74cdff2642SJohn Johansen printk(KERN_INFO "AppArmor: %s\n", str); 75cdff2642SJohn Johansen } 76cdff2642SJohn Johansen 77cdff2642SJohn Johansen /** 78cdff2642SJohn Johansen * kvmalloc - do allocation preferring kmalloc but falling back to vmalloc 79cdff2642SJohn Johansen * @size: size of allocation 80cdff2642SJohn Johansen * 81cdff2642SJohn Johansen * Return: allocated buffer or NULL if failed 82cdff2642SJohn Johansen * 83cdff2642SJohn Johansen * It is possible that policy being loaded from the user is larger than 84cdff2642SJohn Johansen * what can be allocated by kmalloc, in those cases fall back to vmalloc. 85cdff2642SJohn Johansen */ 86cdff2642SJohn Johansen void *kvmalloc(size_t size) 87cdff2642SJohn Johansen { 88cdff2642SJohn Johansen void *buffer = NULL; 89cdff2642SJohn Johansen 90cdff2642SJohn Johansen if (size == 0) 91cdff2642SJohn Johansen return NULL; 92cdff2642SJohn Johansen 93cdff2642SJohn Johansen /* do not attempt kmalloc if we need more than 16 pages at once */ 94cdff2642SJohn Johansen if (size <= (16*PAGE_SIZE)) 95cdff2642SJohn Johansen buffer = kmalloc(size, GFP_NOIO | __GFP_NOWARN); 96cdff2642SJohn Johansen if (!buffer) { 97cdff2642SJohn Johansen /* see kvfree for why size must be at least work_struct size 98cdff2642SJohn Johansen * when allocated via vmalloc 99cdff2642SJohn Johansen */ 100cdff2642SJohn Johansen if (size < sizeof(struct work_struct)) 101cdff2642SJohn Johansen size = sizeof(struct work_struct); 102cdff2642SJohn Johansen buffer = vmalloc(size); 103cdff2642SJohn Johansen } 104cdff2642SJohn Johansen return buffer; 105cdff2642SJohn Johansen } 106cdff2642SJohn Johansen 107cdff2642SJohn Johansen /** 108cdff2642SJohn Johansen * do_vfree - workqueue routine for freeing vmalloced memory 109cdff2642SJohn Johansen * @work: data to be freed 110cdff2642SJohn Johansen * 111cdff2642SJohn Johansen * The work_struct is overlaid to the data being freed, as at the point 112cdff2642SJohn Johansen * the work is scheduled the data is no longer valid, be its freeing 113cdff2642SJohn Johansen * needs to be delayed until safe. 114cdff2642SJohn Johansen */ 115cdff2642SJohn Johansen static void do_vfree(struct work_struct *work) 116cdff2642SJohn Johansen { 117cdff2642SJohn Johansen vfree(work); 118cdff2642SJohn Johansen } 119cdff2642SJohn Johansen 120cdff2642SJohn Johansen /** 121cdff2642SJohn Johansen * kvfree - free an allocation do by kvmalloc 122cdff2642SJohn Johansen * @buffer: buffer to free (MAYBE_NULL) 123cdff2642SJohn Johansen * 124cdff2642SJohn Johansen * Free a buffer allocated by kvmalloc 125cdff2642SJohn Johansen */ 126cdff2642SJohn Johansen void kvfree(void *buffer) 127cdff2642SJohn Johansen { 128cdff2642SJohn Johansen if (is_vmalloc_addr(buffer)) { 129cdff2642SJohn Johansen /* Data is no longer valid so just use the allocated space 130cdff2642SJohn Johansen * as the work_struct 131cdff2642SJohn Johansen */ 132cdff2642SJohn Johansen struct work_struct *work = (struct work_struct *) buffer; 133cdff2642SJohn Johansen INIT_WORK(work, do_vfree); 134cdff2642SJohn Johansen schedule_work(work); 135cdff2642SJohn Johansen } else 136cdff2642SJohn Johansen kfree(buffer); 137cdff2642SJohn Johansen } 138