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Diffstat (limited to 'security/apparmor/lib.c')
-rw-r--r-- | security/apparmor/lib.c | 133 |
1 files changed, 133 insertions, 0 deletions
diff --git a/security/apparmor/lib.c b/security/apparmor/lib.c new file mode 100644 index 000000000000..6e85cdb4303f --- /dev/null +++ b/security/apparmor/lib.c @@ -0,0 +1,133 @@ +/* + * AppArmor security module + * + * This file contains basic common functions used in AppArmor + * + * Copyright (C) 1998-2008 Novell/SUSE + * Copyright 2009-2010 Canonical Ltd. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation, version 2 of the + * License. + */ + +#include <linux/slab.h> +#include <linux/string.h> +#include <linux/vmalloc.h> + +#include "include/audit.h" + + +/** + * aa_split_fqname - split a fqname into a profile and namespace name + * @fqname: a full qualified name in namespace profile format (NOT NULL) + * @ns_name: pointer to portion of the string containing the ns name (NOT NULL) + * + * Returns: profile name or NULL if one is not specified + * + * Split a namespace name from a profile name (see policy.c for naming + * description). If a portion of the name is missing it returns NULL for + * that portion. + * + * NOTE: may modify the @fqname string. The pointers returned point + * into the @fqname string. + */ +char *aa_split_fqname(char *fqname, char **ns_name) +{ + char *name = strim(fqname); + + *ns_name = NULL; + if (name[0] == ':') { + char *split = strchr(&name[1], ':'); + if (split) { + /* overwrite ':' with \0 */ + *split = 0; + name = skip_spaces(split + 1); + } else + /* a ns name without a following profile is allowed */ + name = NULL; + *ns_name = &name[1]; + } + if (name && *name == 0) + name = NULL; + + return name; +} + +/** + * aa_info_message - log a none profile related status message + * @str: message to log + */ +void aa_info_message(const char *str) +{ + if (audit_enabled) { + struct common_audit_data sa; + COMMON_AUDIT_DATA_INIT(&sa, NONE); + sa.aad.info = str; + aa_audit_msg(AUDIT_APPARMOR_STATUS, &sa, NULL); + } + printk(KERN_INFO "AppArmor: %s\n", str); +} + +/** + * kvmalloc - do allocation preferring kmalloc but falling back to vmalloc + * @size: size of allocation + * + * Return: allocated buffer or NULL if failed + * + * It is possible that policy being loaded from the user is larger than + * what can be allocated by kmalloc, in those cases fall back to vmalloc. + */ +void *kvmalloc(size_t size) +{ + void *buffer = NULL; + + if (size == 0) + return NULL; + + /* do not attempt kmalloc if we need more than 16 pages at once */ + if (size <= (16*PAGE_SIZE)) + buffer = kmalloc(size, GFP_NOIO | __GFP_NOWARN); + if (!buffer) { + /* see kvfree for why size must be at least work_struct size + * when allocated via vmalloc + */ + if (size < sizeof(struct work_struct)) + size = sizeof(struct work_struct); + buffer = vmalloc(size); + } + return buffer; +} + +/** + * do_vfree - workqueue routine for freeing vmalloced memory + * @work: data to be freed + * + * The work_struct is overlaid to the data being freed, as at the point + * the work is scheduled the data is no longer valid, be its freeing + * needs to be delayed until safe. + */ +static void do_vfree(struct work_struct *work) +{ + vfree(work); +} + +/** + * kvfree - free an allocation do by kvmalloc + * @buffer: buffer to free (MAYBE_NULL) + * + * Free a buffer allocated by kvmalloc + */ +void kvfree(void *buffer) +{ + if (is_vmalloc_addr(buffer)) { + /* Data is no longer valid so just use the allocated space + * as the work_struct + */ + struct work_struct *work = (struct work_struct *) buffer; + INIT_WORK(work, do_vfree); + schedule_work(work); + } else + kfree(buffer); +} |