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kernel/auditfilter.c
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/* auditfilter.c -- filtering of audit events * * Copyright 2003-2004 Red Hat, Inc. * Copyright 2005 Hewlett-Packard Development Company, L.P. * Copyright 2005 IBM Corporation * * 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; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ #include <linux/kernel.h> #include <linux/audit.h> #include <linux/kthread.h> |
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#include <linux/mutex.h> #include <linux/fs.h> #include <linux/namei.h> |
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#include <linux/netlink.h> |
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#include <linux/sched.h> #include <linux/inotify.h> |
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#include <linux/security.h> |
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#include "audit.h" |
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/* * Locking model: * * audit_filter_mutex: * Synchronizes writes and blocking reads of audit's filterlist * data. Rcu is used to traverse the filterlist and access * contents of structs audit_entry, audit_watch and opaque |
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* LSM rules during filtering. If modified, these structures |
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* must be copied and replace their counterparts in the filterlist. * An audit_parent struct is not accessed during filtering, so may * be written directly provided audit_filter_mutex is held. */ /* * Reference counting: * * audit_parent: lifetime is from audit_init_parent() to receipt of an IN_IGNORED * event. Each audit_watch holds a reference to its associated parent. * * audit_watch: if added to lists, lifetime is from audit_init_watch() to * audit_remove_watch(). Additionally, an audit_watch may exist * temporarily to assist in searching existing filter data. Each * audit_krule holds a reference to its associated watch. */ struct audit_parent { struct list_head ilist; /* entry in inotify registration list */ struct list_head watches; /* associated watches */ struct inotify_watch wdata; /* inotify watch data */ unsigned flags; /* status flags */ }; /* * audit_parent status flags: * * AUDIT_PARENT_INVALID - set anytime rules/watches are auto-removed due to * a filesystem event to ensure we're adding audit watches to a valid parent. * Technically not needed for IN_DELETE_SELF or IN_UNMOUNT events, as we cannot * receive them while we have nameidata, but must be used for IN_MOVE_SELF which * we can receive while holding nameidata. */ #define AUDIT_PARENT_INVALID 0x001 /* Audit filter lists, defined in <linux/audit.h> */ |
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struct list_head audit_filter_list[AUDIT_NR_FILTERS] = { LIST_HEAD_INIT(audit_filter_list[0]), LIST_HEAD_INIT(audit_filter_list[1]), LIST_HEAD_INIT(audit_filter_list[2]), LIST_HEAD_INIT(audit_filter_list[3]), LIST_HEAD_INIT(audit_filter_list[4]), LIST_HEAD_INIT(audit_filter_list[5]), #if AUDIT_NR_FILTERS != 6 #error Fix audit_filter_list initialiser #endif }; |
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DEFINE_MUTEX(audit_filter_mutex); |
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/* Inotify handle */ extern struct inotify_handle *audit_ih; /* Inotify events we care about. */ #define AUDIT_IN_WATCH IN_MOVE|IN_CREATE|IN_DELETE|IN_DELETE_SELF|IN_MOVE_SELF |
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extern int audit_enabled; |
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void audit_free_parent(struct inotify_watch *i_watch) { struct audit_parent *parent; parent = container_of(i_watch, struct audit_parent, wdata); WARN_ON(!list_empty(&parent->watches)); kfree(parent); } static inline void audit_get_watch(struct audit_watch *watch) { atomic_inc(&watch->count); } static void audit_put_watch(struct audit_watch *watch) { if (atomic_dec_and_test(&watch->count)) { WARN_ON(watch->parent); WARN_ON(!list_empty(&watch->rules)); kfree(watch->path); kfree(watch); } } static void audit_remove_watch(struct audit_watch *watch) { list_del(&watch->wlist); put_inotify_watch(&watch->parent->wdata); watch->parent = NULL; audit_put_watch(watch); /* match initial get */ } |
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static inline void audit_free_rule(struct audit_entry *e) |
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{ |
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int i; |
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/* some rules don't have associated watches */ if (e->rule.watch) audit_put_watch(e->rule.watch); |
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if (e->rule.fields) for (i = 0; i < e->rule.field_count; i++) { struct audit_field *f = &e->rule.fields[i]; |
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kfree(f->lsm_str); security_audit_rule_free(f->lsm_rule); |
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} |
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kfree(e->rule.fields); |
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kfree(e->rule.filterkey); |
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kfree(e); } |
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void audit_free_rule_rcu(struct rcu_head *head) |
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{ struct audit_entry *e = container_of(head, struct audit_entry, rcu); audit_free_rule(e); } |
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/* Initialize a parent watch entry. */ static struct audit_parent *audit_init_parent(struct nameidata *ndp) { struct audit_parent *parent; s32 wd; parent = kzalloc(sizeof(*parent), GFP_KERNEL); if (unlikely(!parent)) return ERR_PTR(-ENOMEM); INIT_LIST_HEAD(&parent->watches); parent->flags = 0; inotify_init_watch(&parent->wdata); /* grab a ref so inotify watch hangs around until we take audit_filter_mutex */ get_inotify_watch(&parent->wdata); |
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wd = inotify_add_watch(audit_ih, &parent->wdata, ndp->path.dentry->d_inode, AUDIT_IN_WATCH); |
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if (wd < 0) { audit_free_parent(&parent->wdata); return ERR_PTR(wd); } return parent; } /* Initialize a watch entry. */ static struct audit_watch *audit_init_watch(char *path) { struct audit_watch *watch; watch = kzalloc(sizeof(*watch), GFP_KERNEL); if (unlikely(!watch)) return ERR_PTR(-ENOMEM); INIT_LIST_HEAD(&watch->rules); atomic_set(&watch->count, 1); watch->path = path; watch->dev = (dev_t)-1; watch->ino = (unsigned long)-1; return watch; } |
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/* Initialize an audit filterlist entry. */ static inline struct audit_entry *audit_init_entry(u32 field_count) { struct audit_entry *entry; struct audit_field *fields; entry = kzalloc(sizeof(*entry), GFP_KERNEL); if (unlikely(!entry)) return NULL; fields = kzalloc(sizeof(*fields) * field_count, GFP_KERNEL); if (unlikely(!fields)) { kfree(entry); return NULL; } entry->rule.fields = fields; return entry; } |
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/* Unpack a filter field's string representation from user-space * buffer. */ |
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char *audit_unpack_string(void **bufp, size_t *remain, size_t len) |
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{ char *str; if (!*bufp || (len == 0) || (len > *remain)) return ERR_PTR(-EINVAL); /* Of the currently implemented string fields, PATH_MAX * defines the longest valid length. */ if (len > PATH_MAX) return ERR_PTR(-ENAMETOOLONG); str = kmalloc(len + 1, GFP_KERNEL); if (unlikely(!str)) return ERR_PTR(-ENOMEM); memcpy(str, *bufp, len); str[len] = 0; *bufp += len; *remain -= len; return str; } |
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/* Translate an inode field to kernel respresentation. */ static inline int audit_to_inode(struct audit_krule *krule, struct audit_field *f) { if (krule->listnr != AUDIT_FILTER_EXIT || |
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krule->watch || krule->inode_f || krule->tree) |
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return -EINVAL; krule->inode_f = f; return 0; } /* Translate a watch string to kernel respresentation. */ static int audit_to_watch(struct audit_krule *krule, char *path, int len, u32 op) { struct audit_watch *watch; if (!audit_ih) return -EOPNOTSUPP; if (path[0] != '/' || path[len-1] == '/' || krule->listnr != AUDIT_FILTER_EXIT || op & ~AUDIT_EQUAL || |
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krule->inode_f || krule->watch || krule->tree) |
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return -EINVAL; watch = audit_init_watch(path); if (unlikely(IS_ERR(watch))) return PTR_ERR(watch); audit_get_watch(watch); krule->watch = watch; return 0; } |
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static __u32 *classes[AUDIT_SYSCALL_CLASSES]; int __init audit_register_class(int class, unsigned *list) { __u32 *p = kzalloc(AUDIT_BITMASK_SIZE * sizeof(__u32), GFP_KERNEL); if (!p) return -ENOMEM; while (*list != ~0U) { unsigned n = *list++; if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) { kfree(p); return -EINVAL; } p[AUDIT_WORD(n)] |= AUDIT_BIT(n); } if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) { kfree(p); return -EINVAL; } classes[class] = p; return 0; } |
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int audit_match_class(int class, unsigned syscall) { |
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if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32)) |
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return 0; if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class])) return 0; return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall); } |
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#ifdef CONFIG_AUDITSYSCALL |
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static inline int audit_match_class_bits(int class, u32 *mask) { int i; if (classes[class]) { for (i = 0; i < AUDIT_BITMASK_SIZE; i++) if (mask[i] & classes[class][i]) return 0; } return 1; } static int audit_match_signal(struct audit_entry *entry) { struct audit_field *arch = entry->rule.arch_f; if (!arch) { /* When arch is unspecified, we must check both masks on biarch * as syscall number alone is ambiguous. */ return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, entry->rule.mask) && audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, entry->rule.mask)); } switch(audit_classify_arch(arch->val)) { case 0: /* native */ return (audit_match_class_bits(AUDIT_CLASS_SIGNAL, entry->rule.mask)); case 1: /* 32bit on biarch */ return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32, entry->rule.mask)); default: return 1; } } |
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#endif |
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/* Common user-space to kernel rule translation. */ static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule) { unsigned listnr; struct audit_entry *entry; |
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int i, err; err = -EINVAL; listnr = rule->flags & ~AUDIT_FILTER_PREPEND; switch(listnr) { default: goto exit_err; case AUDIT_FILTER_USER: case AUDIT_FILTER_TYPE: #ifdef CONFIG_AUDITSYSCALL case AUDIT_FILTER_ENTRY: case AUDIT_FILTER_EXIT: case AUDIT_FILTER_TASK: #endif ; } |
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if (unlikely(rule->action == AUDIT_POSSIBLE)) { printk(KERN_ERR "AUDIT_POSSIBLE is deprecated "); goto exit_err; } if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS) |
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goto exit_err; if (rule->field_count > AUDIT_MAX_FIELDS) goto exit_err; err = -ENOMEM; |
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entry = audit_init_entry(rule->field_count); if (!entry) |
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goto exit_err; |
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entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND; entry->rule.listnr = listnr; entry->rule.action = rule->action; entry->rule.field_count = rule->field_count; |
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for (i = 0; i < AUDIT_BITMASK_SIZE; i++) entry->rule.mask[i] = rule->mask[i]; |
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for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) { int bit = AUDIT_BITMASK_SIZE * 32 - i - 1; __u32 *p = &entry->rule.mask[AUDIT_WORD(bit)]; __u32 *class; if (!(*p & AUDIT_BIT(bit))) continue; *p &= ~AUDIT_BIT(bit); class = classes[i]; if (class) { int j; for (j = 0; j < AUDIT_BITMASK_SIZE; j++) entry->rule.mask[j] |= class[j]; } } |
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return entry; exit_err: return ERR_PTR(err); } /* Translate struct audit_rule to kernel's rule respresentation. * Exists for backward compatibility with userspace. */ static struct audit_entry *audit_rule_to_entry(struct audit_rule *rule) { struct audit_entry *entry; |
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struct audit_field *f; |
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int err = 0; |
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int i; |
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entry = audit_to_entry_common(rule); if (IS_ERR(entry)) goto exit_nofree; for (i = 0; i < rule->field_count; i++) { struct audit_field *f = &entry->rule.fields[i]; |
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f->op = rule->fields[i] & (AUDIT_NEGATE|AUDIT_OPERATORS); f->type = rule->fields[i] & ~(AUDIT_NEGATE|AUDIT_OPERATORS); f->val = rule->values[i]; |
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err = -EINVAL; |
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switch(f->type) { |
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default: |
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goto exit_free; |
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case AUDIT_PID: case AUDIT_UID: case AUDIT_EUID: case AUDIT_SUID: case AUDIT_FSUID: case AUDIT_GID: case AUDIT_EGID: case AUDIT_SGID: case AUDIT_FSGID: case AUDIT_LOGINUID: case AUDIT_PERS: |
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case AUDIT_MSGTYPE: |
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case AUDIT_PPID: |
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case AUDIT_DEVMAJOR: case AUDIT_DEVMINOR: case AUDIT_EXIT: case AUDIT_SUCCESS: |
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/* bit ops are only useful on syscall args */ if (f->op == AUDIT_BIT_MASK || f->op == AUDIT_BIT_TEST) { err = -EINVAL; goto exit_free; } break; |
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case AUDIT_ARG0: case AUDIT_ARG1: case AUDIT_ARG2: case AUDIT_ARG3: break; |
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/* arch is only allowed to be = or != */ case AUDIT_ARCH: if ((f->op != AUDIT_NOT_EQUAL) && (f->op != AUDIT_EQUAL) && (f->op != AUDIT_NEGATE) && (f->op)) { err = -EINVAL; goto exit_free; } |
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entry->rule.arch_f = f; |
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break; |
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case AUDIT_PERM: if (f->val & ~15) goto exit_free; break; |
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case AUDIT_INODE: err = audit_to_inode(&entry->rule, f); if (err) goto exit_free; break; |
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} |
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entry->rule.vers_ops = (f->op & AUDIT_OPERATORS) ? 2 : 1; |
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/* Support for legacy operators where * AUDIT_NEGATE bit signifies != and otherwise assumes == */ |
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if (f->op & AUDIT_NEGATE) |
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f->op = AUDIT_NOT_EQUAL; else if (!f->op) f->op = AUDIT_EQUAL; else if (f->op == AUDIT_OPERATORS) { err = -EINVAL; goto exit_free; } |
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} |
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f = entry->rule.inode_f; if (f) { switch(f->op) { case AUDIT_NOT_EQUAL: entry->rule.inode_f = NULL; case AUDIT_EQUAL: break; default: |
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err = -EINVAL; |
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goto exit_free; } } |
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exit_nofree: return entry; exit_free: audit_free_rule(entry); return ERR_PTR(err); |
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} |
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/* Translate struct audit_rule_data to kernel's rule respresentation. */ static struct audit_entry *audit_data_to_entry(struct audit_rule_data *data, size_t datasz) |
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{ |
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int err = 0; struct audit_entry *entry; |
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struct audit_field *f; |
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void *bufp; |
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size_t remain = datasz - sizeof(struct audit_rule_data); |
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int i; |
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char *str; |
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entry = audit_to_entry_common((struct audit_rule *)data); if (IS_ERR(entry)) goto exit_nofree; |
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bufp = data->buf; entry->rule.vers_ops = 2; for (i = 0; i < data->field_count; i++) { struct audit_field *f = &entry->rule.fields[i]; err = -EINVAL; if (!(data->fieldflags[i] & AUDIT_OPERATORS) || data->fieldflags[i] & ~AUDIT_OPERATORS) goto exit_free; f->op = data->fieldflags[i] & AUDIT_OPERATORS; f->type = data->fields[i]; |
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f->val = data->values[i]; |
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f->lsm_str = NULL; f->lsm_rule = NULL; |
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switch(f->type) { |
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case AUDIT_PID: case AUDIT_UID: case AUDIT_EUID: case AUDIT_SUID: case AUDIT_FSUID: case AUDIT_GID: case AUDIT_EGID: case AUDIT_SGID: case AUDIT_FSGID: case AUDIT_LOGINUID: case AUDIT_PERS: |
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case AUDIT_MSGTYPE: case AUDIT_PPID: case AUDIT_DEVMAJOR: case AUDIT_DEVMINOR: case AUDIT_EXIT: case AUDIT_SUCCESS: case AUDIT_ARG0: case AUDIT_ARG1: case AUDIT_ARG2: case AUDIT_ARG3: break; |
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case AUDIT_ARCH: entry->rule.arch_f = f; break; |
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case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: case AUDIT_SUBJ_SEN: case AUDIT_SUBJ_CLR: |
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case AUDIT_OBJ_USER: case AUDIT_OBJ_ROLE: case AUDIT_OBJ_TYPE: case AUDIT_OBJ_LEV_LOW: case AUDIT_OBJ_LEV_HIGH: |
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str = audit_unpack_string(&bufp, &remain, f->val); if (IS_ERR(str)) goto exit_free; entry->rule.buflen += f->val; |
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err = security_audit_rule_init(f->type, f->op, str, |
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(void **)&f->lsm_rule); |
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/* Keep currently invalid fields around in case they * become valid after a policy reload. */ if (err == -EINVAL) { |
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printk(KERN_WARNING "audit rule for LSM " |
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"\'%s\' is invalid ", str); err = 0; } if (err) { kfree(str); goto exit_free; } else |
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f->lsm_str = str; |
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break; |
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case AUDIT_WATCH: str = audit_unpack_string(&bufp, &remain, f->val); if (IS_ERR(str)) goto exit_free; entry->rule.buflen += f->val; err = audit_to_watch(&entry->rule, str, f->val, f->op); if (err) { kfree(str); goto exit_free; } break; |
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case AUDIT_DIR: str = audit_unpack_string(&bufp, &remain, f->val); if (IS_ERR(str)) goto exit_free; entry->rule.buflen += f->val; err = audit_make_tree(&entry->rule, str, f->op); kfree(str); if (err) goto exit_free; break; |
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case AUDIT_INODE: err = audit_to_inode(&entry->rule, f); if (err) goto exit_free; break; |
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case AUDIT_FILTERKEY: err = -EINVAL; if (entry->rule.filterkey || f->val > AUDIT_MAX_KEY_LEN) goto exit_free; str = audit_unpack_string(&bufp, &remain, f->val); if (IS_ERR(str)) goto exit_free; entry->rule.buflen += f->val; entry->rule.filterkey = str; break; |
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case AUDIT_PERM: if (f->val & ~15) goto exit_free; break; |
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default: goto exit_free; |
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} } f = entry->rule.inode_f; if (f) { switch(f->op) { case AUDIT_NOT_EQUAL: entry->rule.inode_f = NULL; case AUDIT_EQUAL: break; default: |
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err = -EINVAL; |
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goto exit_free; |
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} } exit_nofree: return entry; exit_free: audit_free_rule(entry); return ERR_PTR(err); } /* Pack a filter field's string representation into data block. */ |
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static inline size_t audit_pack_string(void **bufp, const char *str) |
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|
665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 |
{ size_t len = strlen(str); memcpy(*bufp, str, len); *bufp += len; return len; } /* Translate kernel rule respresentation to struct audit_rule. * Exists for backward compatibility with userspace. */ static struct audit_rule *audit_krule_to_rule(struct audit_krule *krule) { struct audit_rule *rule; int i; |
4668edc33
|
680 |
rule = kzalloc(sizeof(*rule), GFP_KERNEL); |
93315ed6d
|
681 |
if (unlikely(!rule)) |
0a3b483e8
|
682 |
return NULL; |
93315ed6d
|
683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 |
rule->flags = krule->flags | krule->listnr; rule->action = krule->action; rule->field_count = krule->field_count; for (i = 0; i < rule->field_count; i++) { rule->values[i] = krule->fields[i].val; rule->fields[i] = krule->fields[i].type; if (krule->vers_ops == 1) { if (krule->fields[i].op & AUDIT_NOT_EQUAL) rule->fields[i] |= AUDIT_NEGATE; } else { rule->fields[i] |= krule->fields[i].op; } } for (i = 0; i < AUDIT_BITMASK_SIZE; i++) rule->mask[i] = krule->mask[i]; return rule; } |
fe7752bab
|
702 |
|
93315ed6d
|
703 704 705 706 707 708 709 710 711 |
/* Translate kernel rule respresentation to struct audit_rule_data. */ static struct audit_rule_data *audit_krule_to_data(struct audit_krule *krule) { struct audit_rule_data *data; void *bufp; int i; data = kmalloc(sizeof(*data) + krule->buflen, GFP_KERNEL); if (unlikely(!data)) |
0a3b483e8
|
712 |
return NULL; |
93315ed6d
|
713 714 715 716 717 718 719 720 721 722 723 724 |
memset(data, 0, sizeof(*data)); data->flags = krule->flags | krule->listnr; data->action = krule->action; data->field_count = krule->field_count; bufp = data->buf; for (i = 0; i < data->field_count; i++) { struct audit_field *f = &krule->fields[i]; data->fields[i] = f->type; data->fieldflags[i] = f->op; switch(f->type) { |
3a6b9f85c
|
725 726 727 728 729 |
case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: case AUDIT_SUBJ_SEN: case AUDIT_SUBJ_CLR: |
6e5a2d1d3
|
730 731 732 733 734 |
case AUDIT_OBJ_USER: case AUDIT_OBJ_ROLE: case AUDIT_OBJ_TYPE: case AUDIT_OBJ_LEV_LOW: case AUDIT_OBJ_LEV_HIGH: |
3dc7e3153
|
735 |
data->buflen += data->values[i] = |
04305e4af
|
736 |
audit_pack_string(&bufp, f->lsm_str); |
3dc7e3153
|
737 |
break; |
f368c07d7
|
738 739 740 741 |
case AUDIT_WATCH: data->buflen += data->values[i] = audit_pack_string(&bufp, krule->watch->path); break; |
74c3cbe33
|
742 743 744 745 746 |
case AUDIT_DIR: data->buflen += data->values[i] = audit_pack_string(&bufp, audit_tree_path(krule->tree)); break; |
5adc8a6ad
|
747 748 749 750 |
case AUDIT_FILTERKEY: data->buflen += data->values[i] = audit_pack_string(&bufp, krule->filterkey); break; |
93315ed6d
|
751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 |
default: data->values[i] = f->val; } } for (i = 0; i < AUDIT_BITMASK_SIZE; i++) data->mask[i] = krule->mask[i]; return data; } /* Compare two rules in kernel format. Considered success if rules * don't match. */ static int audit_compare_rule(struct audit_krule *a, struct audit_krule *b) { int i; if (a->flags != b->flags || a->listnr != b->listnr || a->action != b->action || a->field_count != b->field_count) |
fe7752bab
|
770 771 772 |
return 1; for (i = 0; i < a->field_count; i++) { |
93315ed6d
|
773 774 |
if (a->fields[i].type != b->fields[i].type || a->fields[i].op != b->fields[i].op) |
fe7752bab
|
775 |
return 1; |
93315ed6d
|
776 777 |
switch(a->fields[i].type) { |
3a6b9f85c
|
778 779 780 781 782 |
case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: case AUDIT_SUBJ_SEN: case AUDIT_SUBJ_CLR: |
6e5a2d1d3
|
783 784 785 786 787 |
case AUDIT_OBJ_USER: case AUDIT_OBJ_ROLE: case AUDIT_OBJ_TYPE: case AUDIT_OBJ_LEV_LOW: case AUDIT_OBJ_LEV_HIGH: |
04305e4af
|
788 |
if (strcmp(a->fields[i].lsm_str, b->fields[i].lsm_str)) |
3dc7e3153
|
789 790 |
return 1; break; |
f368c07d7
|
791 792 793 794 |
case AUDIT_WATCH: if (strcmp(a->watch->path, b->watch->path)) return 1; break; |
74c3cbe33
|
795 796 797 798 799 |
case AUDIT_DIR: if (strcmp(audit_tree_path(a->tree), audit_tree_path(b->tree))) return 1; break; |
5adc8a6ad
|
800 801 802 803 804 |
case AUDIT_FILTERKEY: /* both filterkeys exist based on above type compare */ if (strcmp(a->filterkey, b->filterkey)) return 1; break; |
93315ed6d
|
805 806 807 808 |
default: if (a->fields[i].val != b->fields[i].val) return 1; } |
fe7752bab
|
809 810 811 812 813 814 815 816 |
} for (i = 0; i < AUDIT_BITMASK_SIZE; i++) if (a->mask[i] != b->mask[i]) return 1; return 0; } |
f368c07d7
|
817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 |
/* Duplicate the given audit watch. The new watch's rules list is initialized * to an empty list and wlist is undefined. */ static struct audit_watch *audit_dupe_watch(struct audit_watch *old) { char *path; struct audit_watch *new; path = kstrdup(old->path, GFP_KERNEL); if (unlikely(!path)) return ERR_PTR(-ENOMEM); new = audit_init_watch(path); if (unlikely(IS_ERR(new))) { kfree(path); goto out; } new->dev = old->dev; new->ino = old->ino; get_inotify_watch(&old->parent->wdata); new->parent = old->parent; out: return new; } |
04305e4af
|
842 |
/* Duplicate LSM field information. The lsm_rule is opaque, so must be |
3dc7e3153
|
843 |
* re-initialized. */ |
d7a96f3a1
|
844 |
static inline int audit_dupe_lsm_field(struct audit_field *df, |
3dc7e3153
|
845 846 847 |
struct audit_field *sf) { int ret = 0; |
04305e4af
|
848 |
char *lsm_str; |
3dc7e3153
|
849 |
|
04305e4af
|
850 851 852 |
/* our own copy of lsm_str */ lsm_str = kstrdup(sf->lsm_str, GFP_KERNEL); if (unlikely(!lsm_str)) |
3e1fbd12c
|
853 |
return -ENOMEM; |
04305e4af
|
854 |
df->lsm_str = lsm_str; |
3dc7e3153
|
855 |
|
04305e4af
|
856 857 858 |
/* our own (refreshed) copy of lsm_rule */ ret = security_audit_rule_init(df->type, df->op, df->lsm_str, (void **)&df->lsm_rule); |
3dc7e3153
|
859 860 861 |
/* Keep currently invalid fields around in case they * become valid after a policy reload. */ if (ret == -EINVAL) { |
d7a96f3a1
|
862 |
printk(KERN_WARNING "audit rule for LSM \'%s\' is " |
04305e4af
|
863 864 |
"invalid ", df->lsm_str); |
3dc7e3153
|
865 866 867 868 869 870 871 |
ret = 0; } return ret; } /* Duplicate an audit rule. This will be a deep copy with the exception |
d7a96f3a1
|
872 |
* of the watch - that pointer is carried over. The LSM specific fields |
3dc7e3153
|
873 |
* will be updated in the copy. The point is to be able to replace the old |
f368c07d7
|
874 875 876 877 878 |
* rule with the new rule in the filterlist, then free the old rule. * The rlist element is undefined; list manipulations are handled apart from * the initial copy. */ static struct audit_entry *audit_dupe_rule(struct audit_krule *old, struct audit_watch *watch) |
3dc7e3153
|
879 880 881 882 |
{ u32 fcount = old->field_count; struct audit_entry *entry; struct audit_krule *new; |
5adc8a6ad
|
883 |
char *fk; |
3dc7e3153
|
884 885 886 887 888 889 890 891 892 893 894 895 896 897 |
int i, err = 0; entry = audit_init_entry(fcount); if (unlikely(!entry)) return ERR_PTR(-ENOMEM); new = &entry->rule; new->vers_ops = old->vers_ops; new->flags = old->flags; new->listnr = old->listnr; new->action = old->action; for (i = 0; i < AUDIT_BITMASK_SIZE; i++) new->mask[i] = old->mask[i]; new->buflen = old->buflen; |
f368c07d7
|
898 899 |
new->inode_f = old->inode_f; new->watch = NULL; |
3dc7e3153
|
900 |
new->field_count = old->field_count; |
74c3cbe33
|
901 902 903 904 905 906 907 908 |
/* * note that we are OK with not refcounting here; audit_match_tree() * never dereferences tree and we can't get false positives there * since we'd have to have rule gone from the list *and* removed * before the chunks found by lookup had been allocated, i.e. before * the beginning of list scan. */ new->tree = old->tree; |
3dc7e3153
|
909 |
memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount); |
04305e4af
|
910 |
/* deep copy this information, updating the lsm_rule fields, because |
3dc7e3153
|
911 912 913 |
* the originals will all be freed when the old rule is freed. */ for (i = 0; i < fcount; i++) { switch (new->fields[i].type) { |
3a6b9f85c
|
914 915 916 917 918 |
case AUDIT_SUBJ_USER: case AUDIT_SUBJ_ROLE: case AUDIT_SUBJ_TYPE: case AUDIT_SUBJ_SEN: case AUDIT_SUBJ_CLR: |
6e5a2d1d3
|
919 920 921 922 923 |
case AUDIT_OBJ_USER: case AUDIT_OBJ_ROLE: case AUDIT_OBJ_TYPE: case AUDIT_OBJ_LEV_LOW: case AUDIT_OBJ_LEV_HIGH: |
d7a96f3a1
|
924 |
err = audit_dupe_lsm_field(&new->fields[i], |
3dc7e3153
|
925 |
&old->fields[i]); |
5adc8a6ad
|
926 927 928 929 930 931 932 |
break; case AUDIT_FILTERKEY: fk = kstrdup(old->filterkey, GFP_KERNEL); if (unlikely(!fk)) err = -ENOMEM; else new->filterkey = fk; |
3dc7e3153
|
933 934 935 936 937 938 |
} if (err) { audit_free_rule(entry); return ERR_PTR(err); } } |
f368c07d7
|
939 940 941 942 |
if (watch) { audit_get_watch(watch); new->watch = watch; } |
3dc7e3153
|
943 944 |
return entry; } |
f368c07d7
|
945 946 947 948 949 950 951 952 |
/* Update inode info in audit rules based on filesystem event. */ static void audit_update_watch(struct audit_parent *parent, const char *dname, dev_t dev, unsigned long ino, unsigned invalidating) { struct audit_watch *owatch, *nwatch, *nextw; struct audit_krule *r, *nextr; struct audit_entry *oentry, *nentry; |
f368c07d7
|
953 954 955 |
mutex_lock(&audit_filter_mutex); list_for_each_entry_safe(owatch, nextw, &parent->watches, wlist) { |
9c937dcc7
|
956 |
if (audit_compare_dname_path(dname, owatch->path, NULL)) |
f368c07d7
|
957 958 959 960 |
continue; /* If the update involves invalidating rules, do the inode-based * filtering now, so we don't omit records. */ |
7b018b288
|
961 |
if (invalidating && current->audit_context && |
f368c07d7
|
962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 |
audit_filter_inodes(current, current->audit_context) == AUDIT_RECORD_CONTEXT) audit_set_auditable(current->audit_context); nwatch = audit_dupe_watch(owatch); if (unlikely(IS_ERR(nwatch))) { mutex_unlock(&audit_filter_mutex); audit_panic("error updating watch, skipping"); return; } nwatch->dev = dev; nwatch->ino = ino; list_for_each_entry_safe(r, nextr, &owatch->rules, rlist) { oentry = container_of(r, struct audit_entry, rule); list_del(&oentry->rule.rlist); list_del_rcu(&oentry->list); nentry = audit_dupe_rule(&oentry->rule, nwatch); if (unlikely(IS_ERR(nentry))) audit_panic("error updating watch, removing"); else { int h = audit_hash_ino((u32)ino); list_add(&nentry->rule.rlist, &nwatch->rules); list_add_rcu(&nentry->list, &audit_inode_hash[h]); } call_rcu(&oentry->rcu, audit_free_rule_rcu); } |
1a6b9f231
|
991 992 993 994 995 996 997 998 999 1000 1001 1002 1003 |
if (audit_enabled) { struct audit_buffer *ab; ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); audit_log_format(ab, "op=updated rules specifying path="); audit_log_untrustedstring(ab, owatch->path); audit_log_format(ab, " with dev=%u ino=%lu ", dev, ino); audit_log_format(ab, " list=%d res=1", r->listnr); audit_log_end(ab); } |
f368c07d7
|
1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 |
audit_remove_watch(owatch); goto add_watch_to_parent; /* event applies to a single watch */ } mutex_unlock(&audit_filter_mutex); return; add_watch_to_parent: list_add(&nwatch->wlist, &parent->watches); mutex_unlock(&audit_filter_mutex); return; } /* Remove all watches & rules associated with a parent that is going away. */ static void audit_remove_parent_watches(struct audit_parent *parent) { struct audit_watch *w, *nextw; struct audit_krule *r, *nextr; struct audit_entry *e; mutex_lock(&audit_filter_mutex); parent->flags |= AUDIT_PARENT_INVALID; list_for_each_entry_safe(w, nextw, &parent->watches, wlist) { list_for_each_entry_safe(r, nextr, &w->rules, rlist) { e = container_of(r, struct audit_entry, rule); |
1a6b9f231
|
1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 |
if (audit_enabled) { struct audit_buffer *ab; ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); audit_log_format(ab, "op=remove rule path="); audit_log_untrustedstring(ab, w->path); if (r->filterkey) { audit_log_format(ab, " key="); audit_log_untrustedstring(ab, r->filterkey); } else audit_log_format(ab, " key=(null)"); audit_log_format(ab, " list=%d res=1", r->listnr); audit_log_end(ab); } |
f368c07d7
|
1044 1045 1046 |
list_del(&r->rlist); list_del_rcu(&e->list); call_rcu(&e->rcu, audit_free_rule_rcu); |
f368c07d7
|
1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 |
} audit_remove_watch(w); } mutex_unlock(&audit_filter_mutex); } /* Unregister inotify watches for parents on in_list. * Generates an IN_IGNORED event. */ static void audit_inotify_unregister(struct list_head *in_list) { struct audit_parent *p, *n; list_for_each_entry_safe(p, n, in_list, ilist) { list_del(&p->ilist); inotify_rm_watch(audit_ih, &p->wdata); /* the put matching the get in audit_do_del_rule() */ put_inotify_watch(&p->wdata); } } /* Find an existing audit rule. * Caller must hold audit_filter_mutex to prevent stale rule data. */ static struct audit_entry *audit_find_rule(struct audit_entry *entry, struct list_head *list) { struct audit_entry *e, *found = NULL; int h; if (entry->rule.watch) { /* we don't know the inode number, so must walk entire hash */ for (h = 0; h < AUDIT_INODE_BUCKETS; h++) { list = &audit_inode_hash[h]; list_for_each_entry(e, list, list) if (!audit_compare_rule(&entry->rule, &e->rule)) { found = e; goto out; } } goto out; } list_for_each_entry(e, list, list) if (!audit_compare_rule(&entry->rule, &e->rule)) { found = e; goto out; } out: return found; } /* Get path information necessary for adding watches. */ static int audit_get_nd(char *path, struct nameidata **ndp, struct nameidata **ndw) { struct nameidata *ndparent, *ndwatch; int err; ndparent = kmalloc(sizeof(*ndparent), GFP_KERNEL); if (unlikely(!ndparent)) return -ENOMEM; ndwatch = kmalloc(sizeof(*ndwatch), GFP_KERNEL); if (unlikely(!ndwatch)) { kfree(ndparent); return -ENOMEM; } err = path_lookup(path, LOOKUP_PARENT, ndparent); if (err) { kfree(ndparent); kfree(ndwatch); return err; } err = path_lookup(path, 0, ndwatch); if (err) { kfree(ndwatch); ndwatch = NULL; } *ndp = ndparent; *ndw = ndwatch; return 0; } /* Release resources used for watch path information. */ static void audit_put_nd(struct nameidata *ndp, struct nameidata *ndw) { if (ndp) { |
1d957f9bf
|
1138 |
path_put(&ndp->path); |
f368c07d7
|
1139 1140 1141 |
kfree(ndp); } if (ndw) { |
1d957f9bf
|
1142 |
path_put(&ndw->path); |
f368c07d7
|
1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 1169 1170 1171 1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 |
kfree(ndw); } } /* Associate the given rule with an existing parent inotify_watch. * Caller must hold audit_filter_mutex. */ static void audit_add_to_parent(struct audit_krule *krule, struct audit_parent *parent) { struct audit_watch *w, *watch = krule->watch; int watch_found = 0; list_for_each_entry(w, &parent->watches, wlist) { if (strcmp(watch->path, w->path)) continue; watch_found = 1; /* put krule's and initial refs to temporary watch */ audit_put_watch(watch); audit_put_watch(watch); audit_get_watch(w); krule->watch = watch = w; break; } if (!watch_found) { get_inotify_watch(&parent->wdata); watch->parent = parent; list_add(&watch->wlist, &parent->watches); } list_add(&krule->rlist, &watch->rules); } /* Find a matching watch entry, or add this one. * Caller must hold audit_filter_mutex. */ static int audit_add_watch(struct audit_krule *krule, struct nameidata *ndp, struct nameidata *ndw) { struct audit_watch *watch = krule->watch; struct inotify_watch *i_watch; struct audit_parent *parent; int ret = 0; /* update watch filter fields */ if (ndw) { |
4ac913785
|
1191 1192 |
watch->dev = ndw->path.dentry->d_inode->i_sb->s_dev; watch->ino = ndw->path.dentry->d_inode->i_ino; |
f368c07d7
|
1193 1194 1195 1196 1197 1198 1199 1200 |
} /* The audit_filter_mutex must not be held during inotify calls because * we hold it during inotify event callback processing. If an existing * inotify watch is found, inotify_find_watch() grabs a reference before * returning. */ mutex_unlock(&audit_filter_mutex); |
4ac913785
|
1201 1202 |
if (inotify_find_watch(audit_ih, ndp->path.dentry->d_inode, &i_watch) < 0) { |
f368c07d7
|
1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223 1224 1225 |
parent = audit_init_parent(ndp); if (IS_ERR(parent)) { /* caller expects mutex locked */ mutex_lock(&audit_filter_mutex); return PTR_ERR(parent); } } else parent = container_of(i_watch, struct audit_parent, wdata); mutex_lock(&audit_filter_mutex); /* parent was moved before we took audit_filter_mutex */ if (parent->flags & AUDIT_PARENT_INVALID) ret = -ENOENT; else audit_add_to_parent(krule, parent); /* match get in audit_init_parent or inotify_find_watch */ put_inotify_watch(&parent->wdata); return ret; } /* Add rule to given filterlist if not a duplicate. */ |
93315ed6d
|
1226 |
static inline int audit_add_rule(struct audit_entry *entry, |
f368c07d7
|
1227 |
struct list_head *list) |
fe7752bab
|
1228 |
{ |
93315ed6d
|
1229 |
struct audit_entry *e; |
f368c07d7
|
1230 1231 |
struct audit_field *inode_f = entry->rule.inode_f; struct audit_watch *watch = entry->rule.watch; |
74c3cbe33
|
1232 |
struct audit_tree *tree = entry->rule.tree; |
6f686d3d1
|
1233 1234 |
struct nameidata *ndp = NULL, *ndw = NULL; int h, err; |
471a5c7c8
|
1235 1236 1237 1238 1239 1240 1241 1242 |
#ifdef CONFIG_AUDITSYSCALL int dont_count = 0; /* If either of these, don't count towards total */ if (entry->rule.listnr == AUDIT_FILTER_USER || entry->rule.listnr == AUDIT_FILTER_TYPE) dont_count = 1; #endif |
f368c07d7
|
1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 1253 |
if (inode_f) { h = audit_hash_ino(inode_f->val); list = &audit_inode_hash[h]; } mutex_lock(&audit_filter_mutex); e = audit_find_rule(entry, list); mutex_unlock(&audit_filter_mutex); if (e) { err = -EEXIST; |
74c3cbe33
|
1254 1255 1256 |
/* normally audit_add_tree_rule() will free it on failure */ if (tree) audit_put_tree(tree); |
f368c07d7
|
1257 1258 |
goto error; } |
fe7752bab
|
1259 |
|
f368c07d7
|
1260 1261 1262 1263 1264 |
/* Avoid calling path_lookup under audit_filter_mutex. */ if (watch) { err = audit_get_nd(watch->path, &ndp, &ndw); if (err) goto error; |
f368c07d7
|
1265 1266 1267 1268 1269 1270 1271 1272 1273 1274 1275 1276 |
} mutex_lock(&audit_filter_mutex); if (watch) { /* audit_filter_mutex is dropped and re-taken during this call */ err = audit_add_watch(&entry->rule, ndp, ndw); if (err) { mutex_unlock(&audit_filter_mutex); goto error; } h = audit_hash_ino((u32)watch->ino); list = &audit_inode_hash[h]; |
fe7752bab
|
1277 |
} |
74c3cbe33
|
1278 1279 1280 1281 1282 1283 1284 |
if (tree) { err = audit_add_tree_rule(&entry->rule); if (err) { mutex_unlock(&audit_filter_mutex); goto error; } } |
fe7752bab
|
1285 |
|
fe7752bab
|
1286 |
if (entry->rule.flags & AUDIT_FILTER_PREPEND) { |
fe7752bab
|
1287 |
list_add_rcu(&entry->list, list); |
6a2bceec0
|
1288 |
entry->rule.flags &= ~AUDIT_FILTER_PREPEND; |
fe7752bab
|
1289 1290 1291 |
} else { list_add_tail_rcu(&entry->list, list); } |
471a5c7c8
|
1292 1293 1294 |
#ifdef CONFIG_AUDITSYSCALL if (!dont_count) audit_n_rules++; |
e54dc2431
|
1295 1296 1297 |
if (!audit_match_signal(entry)) audit_signals++; |
471a5c7c8
|
1298 |
#endif |
f368c07d7
|
1299 |
mutex_unlock(&audit_filter_mutex); |
fe7752bab
|
1300 |
|
6f686d3d1
|
1301 |
audit_put_nd(ndp, ndw); /* NULL args OK */ |
f368c07d7
|
1302 1303 1304 |
return 0; error: |
6f686d3d1
|
1305 |
audit_put_nd(ndp, ndw); /* NULL args OK */ |
f368c07d7
|
1306 1307 1308 |
if (watch) audit_put_watch(watch); /* tmp watch, matches initial get */ return err; |
fe7752bab
|
1309 |
} |
f368c07d7
|
1310 |
/* Remove an existing rule from filterlist. */ |
93315ed6d
|
1311 |
static inline int audit_del_rule(struct audit_entry *entry, |
fe7752bab
|
1312 1313 1314 |
struct list_head *list) { struct audit_entry *e; |
f368c07d7
|
1315 1316 |
struct audit_field *inode_f = entry->rule.inode_f; struct audit_watch *watch, *tmp_watch = entry->rule.watch; |
74c3cbe33
|
1317 |
struct audit_tree *tree = entry->rule.tree; |
f368c07d7
|
1318 1319 |
LIST_HEAD(inotify_list); int h, ret = 0; |
471a5c7c8
|
1320 1321 1322 1323 1324 1325 1326 1327 |
#ifdef CONFIG_AUDITSYSCALL int dont_count = 0; /* If either of these, don't count towards total */ if (entry->rule.listnr == AUDIT_FILTER_USER || entry->rule.listnr == AUDIT_FILTER_TYPE) dont_count = 1; #endif |
f368c07d7
|
1328 1329 1330 1331 1332 |
if (inode_f) { h = audit_hash_ino(inode_f->val); list = &audit_inode_hash[h]; } |
fe7752bab
|
1333 |
|
f368c07d7
|
1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 1350 1351 1352 1353 1354 1355 1356 1357 1358 |
mutex_lock(&audit_filter_mutex); e = audit_find_rule(entry, list); if (!e) { mutex_unlock(&audit_filter_mutex); ret = -ENOENT; goto out; } watch = e->rule.watch; if (watch) { struct audit_parent *parent = watch->parent; list_del(&e->rule.rlist); if (list_empty(&watch->rules)) { audit_remove_watch(watch); if (list_empty(&parent->watches)) { /* Put parent on the inotify un-registration * list. Grab a reference before releasing * audit_filter_mutex, to be released in * audit_inotify_unregister(). */ list_add(&parent->ilist, &inotify_list); get_inotify_watch(&parent->wdata); } |
fe7752bab
|
1359 1360 |
} } |
f368c07d7
|
1361 |
|
74c3cbe33
|
1362 1363 |
if (e->rule.tree) audit_remove_tree_rule(&e->rule); |
f368c07d7
|
1364 1365 |
list_del_rcu(&e->list); call_rcu(&e->rcu, audit_free_rule_rcu); |
471a5c7c8
|
1366 1367 1368 |
#ifdef CONFIG_AUDITSYSCALL if (!dont_count) audit_n_rules--; |
e54dc2431
|
1369 1370 1371 |
if (!audit_match_signal(entry)) audit_signals--; |
471a5c7c8
|
1372 |
#endif |
f368c07d7
|
1373 1374 1375 1376 1377 1378 1379 1380 |
mutex_unlock(&audit_filter_mutex); if (!list_empty(&inotify_list)) audit_inotify_unregister(&inotify_list); out: if (tmp_watch) audit_put_watch(tmp_watch); /* match initial get */ |
74c3cbe33
|
1381 1382 |
if (tree) audit_put_tree(tree); /* that's the temporary one */ |
f368c07d7
|
1383 1384 |
return ret; |
fe7752bab
|
1385 |
} |
93315ed6d
|
1386 1387 |
/* List rules using struct audit_rule. Exists for backward * compatibility with userspace. */ |
9044e6bca
|
1388 |
static void audit_list(int pid, int seq, struct sk_buff_head *q) |
fe7752bab
|
1389 |
{ |
9044e6bca
|
1390 |
struct sk_buff *skb; |
fe7752bab
|
1391 1392 |
struct audit_entry *entry; int i; |
f368c07d7
|
1393 1394 |
/* This is a blocking read, so use audit_filter_mutex instead of rcu * iterator to sync with list writers. */ |
fe7752bab
|
1395 |
for (i=0; i<AUDIT_NR_FILTERS; i++) { |
93315ed6d
|
1396 1397 1398 1399 1400 1401 |
list_for_each_entry(entry, &audit_filter_list[i], list) { struct audit_rule *rule; rule = audit_krule_to_rule(&entry->rule); if (unlikely(!rule)) break; |
9044e6bca
|
1402 |
skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1, |
93315ed6d
|
1403 |
rule, sizeof(*rule)); |
9044e6bca
|
1404 1405 |
if (skb) skb_queue_tail(q, skb); |
93315ed6d
|
1406 1407 |
kfree(rule); } |
fe7752bab
|
1408 |
} |
f368c07d7
|
1409 1410 1411 1412 1413 1414 1415 1416 1417 1418 1419 1420 1421 1422 |
for (i = 0; i < AUDIT_INODE_BUCKETS; i++) { list_for_each_entry(entry, &audit_inode_hash[i], list) { struct audit_rule *rule; rule = audit_krule_to_rule(&entry->rule); if (unlikely(!rule)) break; skb = audit_make_reply(pid, seq, AUDIT_LIST, 0, 1, rule, sizeof(*rule)); if (skb) skb_queue_tail(q, skb); kfree(rule); } } |
9044e6bca
|
1423 1424 1425 |
skb = audit_make_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0); if (skb) skb_queue_tail(q, skb); |
fe7752bab
|
1426 |
} |
93315ed6d
|
1427 |
/* List rules using struct audit_rule_data. */ |
9044e6bca
|
1428 |
static void audit_list_rules(int pid, int seq, struct sk_buff_head *q) |
93315ed6d
|
1429 |
{ |
9044e6bca
|
1430 |
struct sk_buff *skb; |
93315ed6d
|
1431 1432 |
struct audit_entry *e; int i; |
f368c07d7
|
1433 1434 |
/* This is a blocking read, so use audit_filter_mutex instead of rcu * iterator to sync with list writers. */ |
93315ed6d
|
1435 1436 1437 1438 1439 1440 1441 |
for (i=0; i<AUDIT_NR_FILTERS; i++) { list_for_each_entry(e, &audit_filter_list[i], list) { struct audit_rule_data *data; data = audit_krule_to_data(&e->rule); if (unlikely(!data)) break; |
9044e6bca
|
1442 |
skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1, |
f368c07d7
|
1443 1444 1445 1446 1447 1448 1449 1450 1451 1452 1453 1454 1455 1456 1457 |
data, sizeof(*data) + data->buflen); if (skb) skb_queue_tail(q, skb); kfree(data); } } for (i=0; i< AUDIT_INODE_BUCKETS; i++) { list_for_each_entry(e, &audit_inode_hash[i], list) { struct audit_rule_data *data; data = audit_krule_to_data(&e->rule); if (unlikely(!data)) break; skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1, data, sizeof(*data) + data->buflen); |
9044e6bca
|
1458 1459 |
if (skb) skb_queue_tail(q, skb); |
93315ed6d
|
1460 1461 1462 |
kfree(data); } } |
9044e6bca
|
1463 1464 1465 |
skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0); if (skb) skb_queue_tail(q, skb); |
93315ed6d
|
1466 |
} |
5adc8a6ad
|
1467 1468 1469 1470 1471 |
/* Log rule additions and removals */ static void audit_log_rule_change(uid_t loginuid, u32 sid, char *action, struct audit_krule *rule, int res) { struct audit_buffer *ab; |
1a6b9f231
|
1472 1473 |
if (!audit_enabled) return; |
5adc8a6ad
|
1474 1475 1476 1477 1478 1479 1480 |
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE); if (!ab) return; audit_log_format(ab, "auid=%u", loginuid); if (sid) { char *ctx = NULL; u32 len; |
2a862b32f
|
1481 |
if (security_secid_to_secctx(sid, &ctx, &len)) |
5adc8a6ad
|
1482 |
audit_log_format(ab, " ssid=%u", sid); |
2a862b32f
|
1483 |
else { |
5adc8a6ad
|
1484 |
audit_log_format(ab, " subj=%s", ctx); |
2a862b32f
|
1485 1486 |
security_release_secctx(ctx, len); } |
5adc8a6ad
|
1487 |
} |
a17b4ad77
|
1488 |
audit_log_format(ab, " op=%s rule key=", action); |
5adc8a6ad
|
1489 1490 1491 1492 1493 1494 1495 |
if (rule->filterkey) audit_log_untrustedstring(ab, rule->filterkey); else audit_log_format(ab, "(null)"); audit_log_format(ab, " list=%d res=%d", rule->listnr, res); audit_log_end(ab); } |
fe7752bab
|
1496 1497 1498 1499 1500 1501 1502 |
/** * audit_receive_filter - apply all rules to the specified message type * @type: audit message type * @pid: target pid for netlink audit messages * @uid: target uid for netlink audit messages * @seq: netlink audit message sequence (serial) number * @data: payload data |
93315ed6d
|
1503 |
* @datasz: size of payload data |
fe7752bab
|
1504 |
* @loginuid: loginuid of sender |
ce29b682e
|
1505 |
* @sid: SE Linux Security ID of sender |
fe7752bab
|
1506 1507 |
*/ int audit_receive_filter(int type, int pid, int uid, int seq, void *data, |
ce29b682e
|
1508 |
size_t datasz, uid_t loginuid, u32 sid) |
fe7752bab
|
1509 1510 |
{ struct task_struct *tsk; |
9044e6bca
|
1511 |
struct audit_netlink_list *dest; |
93315ed6d
|
1512 1513 |
int err = 0; struct audit_entry *entry; |
fe7752bab
|
1514 1515 1516 |
switch (type) { case AUDIT_LIST: |
93315ed6d
|
1517 |
case AUDIT_LIST_RULES: |
fe7752bab
|
1518 1519 1520 1521 1522 |
/* We can't just spew out the rules here because we might fill * the available socket buffer space and deadlock waiting for * auditctl to read from it... which isn't ever going to * happen if we're actually running in the context of auditctl * trying to _send_ the stuff */ |
9ce34218a
|
1523 |
|
9044e6bca
|
1524 |
dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL); |
fe7752bab
|
1525 1526 |
if (!dest) return -ENOMEM; |
9044e6bca
|
1527 1528 |
dest->pid = pid; skb_queue_head_init(&dest->q); |
fe7752bab
|
1529 |
|
f368c07d7
|
1530 |
mutex_lock(&audit_filter_mutex); |
93315ed6d
|
1531 |
if (type == AUDIT_LIST) |
9044e6bca
|
1532 |
audit_list(pid, seq, &dest->q); |
93315ed6d
|
1533 |
else |
9044e6bca
|
1534 |
audit_list_rules(pid, seq, &dest->q); |
f368c07d7
|
1535 |
mutex_unlock(&audit_filter_mutex); |
9044e6bca
|
1536 1537 |
tsk = kthread_run(audit_send_list, dest, "audit_send_list"); |
fe7752bab
|
1538 |
if (IS_ERR(tsk)) { |
9044e6bca
|
1539 |
skb_queue_purge(&dest->q); |
fe7752bab
|
1540 1541 1542 1543 1544 |
kfree(dest); err = PTR_ERR(tsk); } break; case AUDIT_ADD: |
93315ed6d
|
1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 |
case AUDIT_ADD_RULE: if (type == AUDIT_ADD) entry = audit_rule_to_entry(data); else entry = audit_data_to_entry(data, datasz); if (IS_ERR(entry)) return PTR_ERR(entry); err = audit_add_rule(entry, &audit_filter_list[entry->rule.listnr]); |
5adc8a6ad
|
1555 |
audit_log_rule_change(loginuid, sid, "add", &entry->rule, !err); |
5d3301088
|
1556 1557 |
if (err) |
93315ed6d
|
1558 |
audit_free_rule(entry); |
fe7752bab
|
1559 1560 |
break; case AUDIT_DEL: |
93315ed6d
|
1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 |
case AUDIT_DEL_RULE: if (type == AUDIT_DEL) entry = audit_rule_to_entry(data); else entry = audit_data_to_entry(data, datasz); if (IS_ERR(entry)) return PTR_ERR(entry); err = audit_del_rule(entry, &audit_filter_list[entry->rule.listnr]); |
5adc8a6ad
|
1571 1572 |
audit_log_rule_change(loginuid, sid, "remove", &entry->rule, !err); |
5d3301088
|
1573 |
|
93315ed6d
|
1574 |
audit_free_rule(entry); |
fe7752bab
|
1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 |
break; default: return -EINVAL; } return err; } int audit_comparator(const u32 left, const u32 op, const u32 right) { switch (op) { case AUDIT_EQUAL: return (left == right); case AUDIT_NOT_EQUAL: return (left != right); case AUDIT_LESS_THAN: return (left < right); case AUDIT_LESS_THAN_OR_EQUAL: return (left <= right); case AUDIT_GREATER_THAN: return (left > right); case AUDIT_GREATER_THAN_OR_EQUAL: return (left >= right); |
74f2345b6
|
1598 1599 1600 1601 |
case AUDIT_BIT_MASK: return (left & right); case AUDIT_BIT_TEST: return ((left & right) == right); |
fe7752bab
|
1602 |
} |
d9d9ec6e2
|
1603 1604 |
BUG(); return 0; |
fe7752bab
|
1605 |
} |
f368c07d7
|
1606 1607 |
/* Compare given dentry name with last component in given path, * return of 0 indicates a match. */ |
9c937dcc7
|
1608 1609 |
int audit_compare_dname_path(const char *dname, const char *path, int *dirlen) |
f368c07d7
|
1610 1611 1612 1613 1614 1615 1616 1617 1618 1619 1620 1621 1622 1623 1624 1625 1626 1627 1628 1629 1630 1631 1632 1633 1634 1635 1636 |
{ int dlen, plen; const char *p; if (!dname || !path) return 1; dlen = strlen(dname); plen = strlen(path); if (plen < dlen) return 1; /* disregard trailing slashes */ p = path + plen - 1; while ((*p == '/') && (p > path)) p--; /* find last path component */ p = p - dlen + 1; if (p < path) return 1; else if (p > path) { if (*--p != '/') return 1; else p++; } |
fe7752bab
|
1637 |
|
9c937dcc7
|
1638 1639 1640 |
/* return length of path's directory component */ if (dirlen) *dirlen = p - path; |
f368c07d7
|
1641 1642 |
return strncmp(p, dname, dlen); } |
fe7752bab
|
1643 1644 |
static int audit_filter_user_rules(struct netlink_skb_parms *cb, |
93315ed6d
|
1645 |
struct audit_krule *rule, |
fe7752bab
|
1646 1647 1648 1649 1650 |
enum audit_state *state) { int i; for (i = 0; i < rule->field_count; i++) { |
93315ed6d
|
1651 |
struct audit_field *f = &rule->fields[i]; |
fe7752bab
|
1652 |
int result = 0; |
93315ed6d
|
1653 |
switch (f->type) { |
fe7752bab
|
1654 |
case AUDIT_PID: |
93315ed6d
|
1655 |
result = audit_comparator(cb->creds.pid, f->op, f->val); |
fe7752bab
|
1656 1657 |
break; case AUDIT_UID: |
93315ed6d
|
1658 |
result = audit_comparator(cb->creds.uid, f->op, f->val); |
fe7752bab
|
1659 1660 |
break; case AUDIT_GID: |
93315ed6d
|
1661 |
result = audit_comparator(cb->creds.gid, f->op, f->val); |
fe7752bab
|
1662 1663 |
break; case AUDIT_LOGINUID: |
93315ed6d
|
1664 |
result = audit_comparator(cb->loginuid, f->op, f->val); |
fe7752bab
|
1665 1666 1667 1668 1669 1670 1671 1672 |
break; } if (!result) return 0; } switch (rule->action) { case AUDIT_NEVER: *state = AUDIT_DISABLED; break; |
fe7752bab
|
1673 1674 1675 1676 1677 1678 1679 |
case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break; } return 1; } int audit_filter_user(struct netlink_skb_parms *cb, int type) { |
11f57cedc
|
1680 |
enum audit_state state = AUDIT_DISABLED; |
fe7752bab
|
1681 |
struct audit_entry *e; |
fe7752bab
|
1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 |
int ret = 1; rcu_read_lock(); list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_USER], list) { if (audit_filter_user_rules(cb, &e->rule, &state)) { if (state == AUDIT_DISABLED) ret = 0; break; } } rcu_read_unlock(); return ret; /* Audit by default */ } int audit_filter_type(int type) { struct audit_entry *e; int result = 0; |
9ce34218a
|
1701 |
|
fe7752bab
|
1702 1703 1704 1705 1706 1707 |
rcu_read_lock(); if (list_empty(&audit_filter_list[AUDIT_FILTER_TYPE])) goto unlock_and_return; list_for_each_entry_rcu(e, &audit_filter_list[AUDIT_FILTER_TYPE], list) { |
fe7752bab
|
1708 |
int i; |
93315ed6d
|
1709 1710 1711 1712 |
for (i = 0; i < e->rule.field_count; i++) { struct audit_field *f = &e->rule.fields[i]; if (f->type == AUDIT_MSGTYPE) { result = audit_comparator(type, f->op, f->val); |
fe7752bab
|
1713 1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 |
if (!result) break; } } if (result) goto unlock_and_return; } unlock_and_return: rcu_read_unlock(); return result; } |
3dc7e3153
|
1724 |
|
04305e4af
|
1725 |
/* This function will re-initialize the lsm_rule field of all applicable rules. |
d7a96f3a1
|
1726 |
* It will traverse the filter lists serarching for rules that contain LSM |
3dc7e3153
|
1727 |
* specific filter fields. When such a rule is found, it is copied, the |
d7a96f3a1
|
1728 |
* LSM field is re-initialized, and the old rule is replaced with the |
3dc7e3153
|
1729 |
* updated rule. */ |
d7a96f3a1
|
1730 |
int audit_update_lsm_rules(void) |
3dc7e3153
|
1731 1732 |
{ struct audit_entry *entry, *n, *nentry; |
f368c07d7
|
1733 |
struct audit_watch *watch; |
74c3cbe33
|
1734 |
struct audit_tree *tree; |
3dc7e3153
|
1735 |
int i, err = 0; |
f368c07d7
|
1736 1737 |
/* audit_filter_mutex synchronizes the writers */ mutex_lock(&audit_filter_mutex); |
3dc7e3153
|
1738 1739 1740 |
for (i = 0; i < AUDIT_NR_FILTERS; i++) { list_for_each_entry_safe(entry, n, &audit_filter_list[i], list) { |
d7a96f3a1
|
1741 |
if (!security_audit_rule_known(&entry->rule)) |
3dc7e3153
|
1742 |
continue; |
f368c07d7
|
1743 |
watch = entry->rule.watch; |
74c3cbe33
|
1744 |
tree = entry->rule.tree; |
f368c07d7
|
1745 |
nentry = audit_dupe_rule(&entry->rule, watch); |
3dc7e3153
|
1746 1747 1748 1749 1750 |
if (unlikely(IS_ERR(nentry))) { /* save the first error encountered for the * return value */ if (!err) err = PTR_ERR(nentry); |
d7a96f3a1
|
1751 |
audit_panic("error updating LSM filters"); |
f368c07d7
|
1752 1753 |
if (watch) list_del(&entry->rule.rlist); |
3dc7e3153
|
1754 1755 |
list_del_rcu(&entry->list); } else { |
f368c07d7
|
1756 1757 1758 1759 |
if (watch) { list_add(&nentry->rule.rlist, &watch->rules); list_del(&entry->rule.rlist); |
74c3cbe33
|
1760 1761 1762 |
} else if (tree) list_replace_init(&entry->rule.rlist, &nentry->rule.rlist); |
3dc7e3153
|
1763 1764 1765 1766 1767 |
list_replace_rcu(&entry->list, &nentry->list); } call_rcu(&entry->rcu, audit_free_rule_rcu); } } |
f368c07d7
|
1768 |
mutex_unlock(&audit_filter_mutex); |
3dc7e3153
|
1769 1770 1771 |
return err; } |
f368c07d7
|
1772 1773 1774 1775 1776 1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787 1788 1789 1790 1791 1792 1793 1794 1795 |
/* Update watch data in audit rules based on inotify events. */ void audit_handle_ievent(struct inotify_watch *i_watch, u32 wd, u32 mask, u32 cookie, const char *dname, struct inode *inode) { struct audit_parent *parent; parent = container_of(i_watch, struct audit_parent, wdata); if (mask & (IN_CREATE|IN_MOVED_TO) && inode) audit_update_watch(parent, dname, inode->i_sb->s_dev, inode->i_ino, 0); else if (mask & (IN_DELETE|IN_MOVED_FROM)) audit_update_watch(parent, dname, (dev_t)-1, (unsigned long)-1, 1); /* inotify automatically removes the watch and sends IN_IGNORED */ else if (mask & (IN_DELETE_SELF|IN_UNMOUNT)) audit_remove_parent_watches(parent); /* inotify does not remove the watch, so remove it manually */ else if(mask & IN_MOVE_SELF) { audit_remove_parent_watches(parent); inotify_remove_watch_locked(audit_ih, i_watch); } else if (mask & IN_IGNORED) put_inotify_watch(i_watch); } |