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381a80e6df
There is what we believe to be a false positive reported by lockdep. inotify_inode_queue_event() => take inotify_mutex => kernel_event() => kmalloc() => SLOB => alloc_pages_node() => page reclaim => slab reclaim => dcache reclaim => inotify_inode_is_dead => take inotify_mutex => deadlock The plan is to fix this via lockdep annotation, but that is proving to be quite involved. The patch flips the allocation over to GFP_NFS to shut the warning up, for the 2.6.30 release. Hopefully we will fix this for real in 2.6.31. I'll queue a patch in -mm to switch it back to GFP_KERNEL so we don't forget. ================================= [ INFO: inconsistent lock state ] 2.6.30-rc2-next-20090417 #203 --------------------------------- inconsistent {RECLAIM_FS-ON-W} -> {IN-RECLAIM_FS-W} usage. kswapd0/380 [HC0[0]:SC0[0]:HE1:SE1] takes: (&inode->inotify_mutex){+.+.?.}, at: [<ffffffff8112f1b5>] inotify_inode_is_dead+0x35/0xb0 {RECLAIM_FS-ON-W} state was registered at: [<ffffffff81079188>] mark_held_locks+0x68/0x90 [<ffffffff810792a5>] lockdep_trace_alloc+0xf5/0x100 [<ffffffff810f5261>] __kmalloc_node+0x31/0x1e0 [<ffffffff81130652>] kernel_event+0xe2/0x190 [<ffffffff81130826>] inotify_dev_queue_event+0x126/0x230 [<ffffffff8112f096>] inotify_inode_queue_event+0xc6/0x110 [<ffffffff8110444d>] vfs_create+0xcd/0x140 [<ffffffff8110825d>] do_filp_open+0x88d/0xa20 [<ffffffff810f6b68>] do_sys_open+0x98/0x140 [<ffffffff810f6c50>] sys_open+0x20/0x30 [<ffffffff8100c272>] system_call_fastpath+0x16/0x1b [<ffffffffffffffff>] 0xffffffffffffffff irq event stamp: 690455 hardirqs last enabled at (690455): [<ffffffff81564fe4>] _spin_unlock_irqrestore+0x44/0x80 hardirqs last disabled at (690454): [<ffffffff81565372>] _spin_lock_irqsave+0x32/0xa0 softirqs last enabled at (690178): [<ffffffff81052282>] __do_softirq+0x202/0x220 softirqs last disabled at (690157): [<ffffffff8100d50c>] call_softirq+0x1c/0x50 other info that might help us debug this: 2 locks held by kswapd0/380: #0: (shrinker_rwsem){++++..}, at: [<ffffffff810d0bd7>] shrink_slab+0x37/0x180 #1: (&type->s_umount_key#17){++++..}, at: [<ffffffff8110cfbf>] shrink_dcache_memory+0x11f/0x1e0 stack backtrace: Pid: 380, comm: kswapd0 Not tainted 2.6.30-rc2-next-20090417 #203 Call Trace: [<ffffffff810789ef>] print_usage_bug+0x19f/0x200 [<ffffffff81018bff>] ? save_stack_trace+0x2f/0x50 [<ffffffff81078f0b>] mark_lock+0x4bb/0x6d0 [<ffffffff810799e0>] ? check_usage_forwards+0x0/0xc0 [<ffffffff8107b142>] __lock_acquire+0xc62/0x1ae0 [<ffffffff810f478c>] ? slob_free+0x10c/0x370 [<ffffffff8107c0a1>] lock_acquire+0xe1/0x120 [<ffffffff8112f1b5>] ? inotify_inode_is_dead+0x35/0xb0 [<ffffffff81562d43>] mutex_lock_nested+0x63/0x420 [<ffffffff8112f1b5>] ? inotify_inode_is_dead+0x35/0xb0 [<ffffffff8112f1b5>] ? inotify_inode_is_dead+0x35/0xb0 [<ffffffff81012fe9>] ? sched_clock+0x9/0x10 [<ffffffff81077165>] ? lock_release_holdtime+0x35/0x1c0 [<ffffffff8112f1b5>] inotify_inode_is_dead+0x35/0xb0 [<ffffffff8110c9dc>] dentry_iput+0xbc/0xe0 [<ffffffff8110cb23>] d_kill+0x33/0x60 [<ffffffff8110ce23>] __shrink_dcache_sb+0x2d3/0x350 [<ffffffff8110cffa>] shrink_dcache_memory+0x15a/0x1e0 [<ffffffff810d0cc5>] shrink_slab+0x125/0x180 [<ffffffff810d1540>] kswapd+0x560/0x7a0 [<ffffffff810ce160>] ? isolate_pages_global+0x0/0x2c0 [<ffffffff81065a30>] ? autoremove_wake_function+0x0/0x40 [<ffffffff8107953d>] ? trace_hardirqs_on+0xd/0x10 [<ffffffff810d0fe0>] ? kswapd+0x0/0x7a0 [<ffffffff8106555b>] kthread+0x5b/0xa0 [<ffffffff8100d40a>] child_rip+0xa/0x20 [<ffffffff8100cdd0>] ? restore_args+0x0/0x30 [<ffffffff81065500>] ? kthread+0x0/0xa0 [<ffffffff8100d400>] ? child_rip+0x0/0x20 [eparis@redhat.com: fix audit too] Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Matt Mackall <mpm@selenic.com> Cc: Christoph Lameter <clameter@sgi.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com> Signed-off-by: Eric Paris <eparis@redhat.com> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1856 lines
46 KiB
C
1856 lines
46 KiB
C
/* auditfilter.c -- filtering of audit events
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*
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* Copyright 2003-2004 Red Hat, Inc.
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* Copyright 2005 Hewlett-Packard Development Company, L.P.
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* Copyright 2005 IBM Corporation
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/kernel.h>
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#include <linux/audit.h>
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#include <linux/kthread.h>
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#include <linux/mutex.h>
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#include <linux/fs.h>
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#include <linux/namei.h>
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#include <linux/netlink.h>
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#include <linux/sched.h>
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#include <linux/inotify.h>
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#include <linux/security.h>
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#include "audit.h"
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/*
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* Locking model:
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*
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* audit_filter_mutex:
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* Synchronizes writes and blocking reads of audit's filterlist
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* data. Rcu is used to traverse the filterlist and access
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* 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.
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* An audit_parent struct is not accessed during filtering, so may
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* be written directly provided audit_filter_mutex is held.
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*/
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/*
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* Reference counting:
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*
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* audit_parent: lifetime is from audit_init_parent() to receipt of an IN_IGNORED
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* event. Each audit_watch holds a reference to its associated parent.
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*
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* audit_watch: if added to lists, lifetime is from audit_init_watch() to
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* audit_remove_watch(). Additionally, an audit_watch may exist
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* temporarily to assist in searching existing filter data. Each
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* audit_krule holds a reference to its associated watch.
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*/
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struct audit_parent {
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struct list_head ilist; /* entry in inotify registration list */
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struct list_head watches; /* associated watches */
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struct inotify_watch wdata; /* inotify watch data */
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unsigned flags; /* status flags */
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};
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/*
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* audit_parent status flags:
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*
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* AUDIT_PARENT_INVALID - set anytime rules/watches are auto-removed due to
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* a filesystem event to ensure we're adding audit watches to a valid parent.
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* Technically not needed for IN_DELETE_SELF or IN_UNMOUNT events, as we cannot
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* receive them while we have nameidata, but must be used for IN_MOVE_SELF which
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* we can receive while holding nameidata.
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*/
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#define AUDIT_PARENT_INVALID 0x001
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/* Audit filter lists, defined in <linux/audit.h> */
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struct list_head audit_filter_list[AUDIT_NR_FILTERS] = {
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LIST_HEAD_INIT(audit_filter_list[0]),
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LIST_HEAD_INIT(audit_filter_list[1]),
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LIST_HEAD_INIT(audit_filter_list[2]),
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LIST_HEAD_INIT(audit_filter_list[3]),
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LIST_HEAD_INIT(audit_filter_list[4]),
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LIST_HEAD_INIT(audit_filter_list[5]),
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#if AUDIT_NR_FILTERS != 6
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#error Fix audit_filter_list initialiser
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#endif
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};
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static struct list_head audit_rules_list[AUDIT_NR_FILTERS] = {
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LIST_HEAD_INIT(audit_rules_list[0]),
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LIST_HEAD_INIT(audit_rules_list[1]),
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LIST_HEAD_INIT(audit_rules_list[2]),
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LIST_HEAD_INIT(audit_rules_list[3]),
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LIST_HEAD_INIT(audit_rules_list[4]),
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LIST_HEAD_INIT(audit_rules_list[5]),
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};
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DEFINE_MUTEX(audit_filter_mutex);
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/* Inotify events we care about. */
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#define AUDIT_IN_WATCH IN_MOVE|IN_CREATE|IN_DELETE|IN_DELETE_SELF|IN_MOVE_SELF
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void audit_free_parent(struct inotify_watch *i_watch)
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{
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struct audit_parent *parent;
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parent = container_of(i_watch, struct audit_parent, wdata);
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WARN_ON(!list_empty(&parent->watches));
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kfree(parent);
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}
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static inline void audit_get_watch(struct audit_watch *watch)
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{
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atomic_inc(&watch->count);
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}
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static void audit_put_watch(struct audit_watch *watch)
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{
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if (atomic_dec_and_test(&watch->count)) {
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WARN_ON(watch->parent);
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WARN_ON(!list_empty(&watch->rules));
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kfree(watch->path);
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kfree(watch);
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}
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}
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static void audit_remove_watch(struct audit_watch *watch)
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{
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list_del(&watch->wlist);
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put_inotify_watch(&watch->parent->wdata);
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watch->parent = NULL;
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audit_put_watch(watch); /* match initial get */
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}
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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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struct audit_krule *erule = &e->rule;
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/* some rules don't have associated watches */
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if (erule->watch)
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audit_put_watch(erule->watch);
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if (erule->fields)
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for (i = 0; i < erule->field_count; i++) {
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struct audit_field *f = &erule->fields[i];
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kfree(f->lsm_str);
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security_audit_rule_free(f->lsm_rule);
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}
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kfree(erule->fields);
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kfree(erule->filterkey);
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kfree(e);
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}
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void audit_free_rule_rcu(struct rcu_head *head)
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{
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struct audit_entry *e = container_of(head, struct audit_entry, rcu);
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audit_free_rule(e);
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}
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/* Initialize a parent watch entry. */
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static struct audit_parent *audit_init_parent(struct nameidata *ndp)
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{
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struct audit_parent *parent;
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s32 wd;
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parent = kzalloc(sizeof(*parent), GFP_KERNEL);
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if (unlikely(!parent))
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return ERR_PTR(-ENOMEM);
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INIT_LIST_HEAD(&parent->watches);
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parent->flags = 0;
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inotify_init_watch(&parent->wdata);
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/* grab a ref so inotify watch hangs around until we take audit_filter_mutex */
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get_inotify_watch(&parent->wdata);
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wd = inotify_add_watch(audit_ih, &parent->wdata,
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ndp->path.dentry->d_inode, AUDIT_IN_WATCH);
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if (wd < 0) {
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audit_free_parent(&parent->wdata);
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return ERR_PTR(wd);
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}
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return parent;
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}
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/* Initialize a watch entry. */
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static struct audit_watch *audit_init_watch(char *path)
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{
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struct audit_watch *watch;
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watch = kzalloc(sizeof(*watch), GFP_KERNEL);
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if (unlikely(!watch))
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return ERR_PTR(-ENOMEM);
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INIT_LIST_HEAD(&watch->rules);
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atomic_set(&watch->count, 1);
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watch->path = path;
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watch->dev = (dev_t)-1;
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watch->ino = (unsigned long)-1;
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return watch;
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}
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/* Initialize an audit filterlist entry. */
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static inline struct audit_entry *audit_init_entry(u32 field_count)
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{
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struct audit_entry *entry;
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struct audit_field *fields;
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entry = kzalloc(sizeof(*entry), GFP_KERNEL);
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if (unlikely(!entry))
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return NULL;
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fields = kzalloc(sizeof(*fields) * field_count, GFP_KERNEL);
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if (unlikely(!fields)) {
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kfree(entry);
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return NULL;
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}
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entry->rule.fields = fields;
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return entry;
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}
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/* Unpack a filter field's string representation from user-space
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* buffer. */
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char *audit_unpack_string(void **bufp, size_t *remain, size_t len)
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{
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char *str;
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if (!*bufp || (len == 0) || (len > *remain))
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return ERR_PTR(-EINVAL);
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/* Of the currently implemented string fields, PATH_MAX
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* defines the longest valid length.
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*/
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if (len > PATH_MAX)
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return ERR_PTR(-ENAMETOOLONG);
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str = kmalloc(len + 1, GFP_KERNEL);
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if (unlikely(!str))
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return ERR_PTR(-ENOMEM);
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memcpy(str, *bufp, len);
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str[len] = 0;
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*bufp += len;
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*remain -= len;
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return str;
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}
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/* Translate an inode field to kernel respresentation. */
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static inline int audit_to_inode(struct audit_krule *krule,
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struct audit_field *f)
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{
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if (krule->listnr != AUDIT_FILTER_EXIT ||
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krule->watch || krule->inode_f || krule->tree ||
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(f->op != Audit_equal && f->op != Audit_not_equal))
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return -EINVAL;
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krule->inode_f = f;
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return 0;
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}
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/* Translate a watch string to kernel respresentation. */
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static int audit_to_watch(struct audit_krule *krule, char *path, int len,
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u32 op)
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{
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struct audit_watch *watch;
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if (!audit_ih)
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return -EOPNOTSUPP;
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if (path[0] != '/' || path[len-1] == '/' ||
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krule->listnr != AUDIT_FILTER_EXIT ||
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op != Audit_equal ||
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krule->inode_f || krule->watch || krule->tree)
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return -EINVAL;
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watch = audit_init_watch(path);
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if (IS_ERR(watch))
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return PTR_ERR(watch);
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audit_get_watch(watch);
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krule->watch = watch;
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return 0;
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}
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static __u32 *classes[AUDIT_SYSCALL_CLASSES];
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int __init audit_register_class(int class, unsigned *list)
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{
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__u32 *p = kzalloc(AUDIT_BITMASK_SIZE * sizeof(__u32), GFP_KERNEL);
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if (!p)
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return -ENOMEM;
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while (*list != ~0U) {
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unsigned n = *list++;
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if (n >= AUDIT_BITMASK_SIZE * 32 - AUDIT_SYSCALL_CLASSES) {
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kfree(p);
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return -EINVAL;
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}
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p[AUDIT_WORD(n)] |= AUDIT_BIT(n);
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}
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if (class >= AUDIT_SYSCALL_CLASSES || classes[class]) {
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kfree(p);
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return -EINVAL;
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}
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classes[class] = p;
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return 0;
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}
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int audit_match_class(int class, unsigned syscall)
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{
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if (unlikely(syscall >= AUDIT_BITMASK_SIZE * 32))
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return 0;
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if (unlikely(class >= AUDIT_SYSCALL_CLASSES || !classes[class]))
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return 0;
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return classes[class][AUDIT_WORD(syscall)] & AUDIT_BIT(syscall);
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}
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#ifdef CONFIG_AUDITSYSCALL
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static inline int audit_match_class_bits(int class, u32 *mask)
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{
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int i;
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if (classes[class]) {
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for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
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if (mask[i] & classes[class][i])
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return 0;
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}
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return 1;
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}
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static int audit_match_signal(struct audit_entry *entry)
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{
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struct audit_field *arch = entry->rule.arch_f;
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if (!arch) {
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/* When arch is unspecified, we must check both masks on biarch
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* as syscall number alone is ambiguous. */
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return (audit_match_class_bits(AUDIT_CLASS_SIGNAL,
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entry->rule.mask) &&
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audit_match_class_bits(AUDIT_CLASS_SIGNAL_32,
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entry->rule.mask));
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}
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switch(audit_classify_arch(arch->val)) {
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case 0: /* native */
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return (audit_match_class_bits(AUDIT_CLASS_SIGNAL,
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entry->rule.mask));
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case 1: /* 32bit on biarch */
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return (audit_match_class_bits(AUDIT_CLASS_SIGNAL_32,
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entry->rule.mask));
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default:
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return 1;
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}
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}
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#endif
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/* Common user-space to kernel rule translation. */
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static inline struct audit_entry *audit_to_entry_common(struct audit_rule *rule)
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{
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unsigned listnr;
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struct audit_entry *entry;
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int i, err;
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err = -EINVAL;
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listnr = rule->flags & ~AUDIT_FILTER_PREPEND;
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switch(listnr) {
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default:
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goto exit_err;
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case AUDIT_FILTER_USER:
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case AUDIT_FILTER_TYPE:
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#ifdef CONFIG_AUDITSYSCALL
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case AUDIT_FILTER_ENTRY:
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case AUDIT_FILTER_EXIT:
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case AUDIT_FILTER_TASK:
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#endif
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;
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}
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if (unlikely(rule->action == AUDIT_POSSIBLE)) {
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printk(KERN_ERR "AUDIT_POSSIBLE is deprecated\n");
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goto exit_err;
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}
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if (rule->action != AUDIT_NEVER && rule->action != AUDIT_ALWAYS)
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goto exit_err;
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if (rule->field_count > AUDIT_MAX_FIELDS)
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goto exit_err;
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err = -ENOMEM;
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entry = audit_init_entry(rule->field_count);
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if (!entry)
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goto exit_err;
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entry->rule.flags = rule->flags & AUDIT_FILTER_PREPEND;
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entry->rule.listnr = listnr;
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entry->rule.action = rule->action;
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entry->rule.field_count = rule->field_count;
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for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
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entry->rule.mask[i] = rule->mask[i];
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for (i = 0; i < AUDIT_SYSCALL_CLASSES; i++) {
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int bit = AUDIT_BITMASK_SIZE * 32 - i - 1;
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__u32 *p = &entry->rule.mask[AUDIT_WORD(bit)];
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__u32 *class;
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if (!(*p & AUDIT_BIT(bit)))
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continue;
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*p &= ~AUDIT_BIT(bit);
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class = classes[i];
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if (class) {
|
|
int j;
|
|
for (j = 0; j < AUDIT_BITMASK_SIZE; j++)
|
|
entry->rule.mask[j] |= class[j];
|
|
}
|
|
}
|
|
|
|
return entry;
|
|
|
|
exit_err:
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
static u32 audit_ops[] =
|
|
{
|
|
[Audit_equal] = AUDIT_EQUAL,
|
|
[Audit_not_equal] = AUDIT_NOT_EQUAL,
|
|
[Audit_bitmask] = AUDIT_BIT_MASK,
|
|
[Audit_bittest] = AUDIT_BIT_TEST,
|
|
[Audit_lt] = AUDIT_LESS_THAN,
|
|
[Audit_gt] = AUDIT_GREATER_THAN,
|
|
[Audit_le] = AUDIT_LESS_THAN_OR_EQUAL,
|
|
[Audit_ge] = AUDIT_GREATER_THAN_OR_EQUAL,
|
|
};
|
|
|
|
static u32 audit_to_op(u32 op)
|
|
{
|
|
u32 n;
|
|
for (n = Audit_equal; n < Audit_bad && audit_ops[n] != op; n++)
|
|
;
|
|
return n;
|
|
}
|
|
|
|
|
|
/* 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;
|
|
int err = 0;
|
|
int i;
|
|
|
|
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];
|
|
u32 n;
|
|
|
|
n = rule->fields[i] & (AUDIT_NEGATE|AUDIT_OPERATORS);
|
|
|
|
/* Support for legacy operators where
|
|
* AUDIT_NEGATE bit signifies != and otherwise assumes == */
|
|
if (n & AUDIT_NEGATE)
|
|
f->op = Audit_not_equal;
|
|
else if (!n)
|
|
f->op = Audit_equal;
|
|
else
|
|
f->op = audit_to_op(n);
|
|
|
|
entry->rule.vers_ops = (n & AUDIT_OPERATORS) ? 2 : 1;
|
|
|
|
f->type = rule->fields[i] & ~(AUDIT_NEGATE|AUDIT_OPERATORS);
|
|
f->val = rule->values[i];
|
|
|
|
err = -EINVAL;
|
|
if (f->op == Audit_bad)
|
|
goto exit_free;
|
|
|
|
switch(f->type) {
|
|
default:
|
|
goto exit_free;
|
|
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:
|
|
case AUDIT_MSGTYPE:
|
|
case AUDIT_PPID:
|
|
case AUDIT_DEVMAJOR:
|
|
case AUDIT_DEVMINOR:
|
|
case AUDIT_EXIT:
|
|
case AUDIT_SUCCESS:
|
|
/* bit ops are only useful on syscall args */
|
|
if (f->op == Audit_bitmask || f->op == Audit_bittest)
|
|
goto exit_free;
|
|
break;
|
|
case AUDIT_ARG0:
|
|
case AUDIT_ARG1:
|
|
case AUDIT_ARG2:
|
|
case AUDIT_ARG3:
|
|
break;
|
|
/* arch is only allowed to be = or != */
|
|
case AUDIT_ARCH:
|
|
if (f->op != Audit_not_equal && f->op != Audit_equal)
|
|
goto exit_free;
|
|
entry->rule.arch_f = f;
|
|
break;
|
|
case AUDIT_PERM:
|
|
if (f->val & ~15)
|
|
goto exit_free;
|
|
break;
|
|
case AUDIT_FILETYPE:
|
|
if ((f->val & ~S_IFMT) > S_IFMT)
|
|
goto exit_free;
|
|
break;
|
|
case AUDIT_INODE:
|
|
err = audit_to_inode(&entry->rule, f);
|
|
if (err)
|
|
goto exit_free;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal)
|
|
entry->rule.inode_f = NULL;
|
|
|
|
exit_nofree:
|
|
return entry;
|
|
|
|
exit_free:
|
|
audit_free_rule(entry);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
/* 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)
|
|
{
|
|
int err = 0;
|
|
struct audit_entry *entry;
|
|
void *bufp;
|
|
size_t remain = datasz - sizeof(struct audit_rule_data);
|
|
int i;
|
|
char *str;
|
|
|
|
entry = audit_to_entry_common((struct audit_rule *)data);
|
|
if (IS_ERR(entry))
|
|
goto exit_nofree;
|
|
|
|
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;
|
|
|
|
f->op = audit_to_op(data->fieldflags[i]);
|
|
if (f->op == Audit_bad)
|
|
goto exit_free;
|
|
|
|
f->type = data->fields[i];
|
|
f->val = data->values[i];
|
|
f->lsm_str = NULL;
|
|
f->lsm_rule = NULL;
|
|
switch(f->type) {
|
|
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:
|
|
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;
|
|
case AUDIT_ARCH:
|
|
entry->rule.arch_f = f;
|
|
break;
|
|
case AUDIT_SUBJ_USER:
|
|
case AUDIT_SUBJ_ROLE:
|
|
case AUDIT_SUBJ_TYPE:
|
|
case AUDIT_SUBJ_SEN:
|
|
case AUDIT_SUBJ_CLR:
|
|
case AUDIT_OBJ_USER:
|
|
case AUDIT_OBJ_ROLE:
|
|
case AUDIT_OBJ_TYPE:
|
|
case AUDIT_OBJ_LEV_LOW:
|
|
case AUDIT_OBJ_LEV_HIGH:
|
|
str = audit_unpack_string(&bufp, &remain, f->val);
|
|
if (IS_ERR(str))
|
|
goto exit_free;
|
|
entry->rule.buflen += f->val;
|
|
|
|
err = security_audit_rule_init(f->type, f->op, str,
|
|
(void **)&f->lsm_rule);
|
|
/* Keep currently invalid fields around in case they
|
|
* become valid after a policy reload. */
|
|
if (err == -EINVAL) {
|
|
printk(KERN_WARNING "audit rule for LSM "
|
|
"\'%s\' is invalid\n", str);
|
|
err = 0;
|
|
}
|
|
if (err) {
|
|
kfree(str);
|
|
goto exit_free;
|
|
} else
|
|
f->lsm_str = str;
|
|
break;
|
|
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;
|
|
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;
|
|
case AUDIT_INODE:
|
|
err = audit_to_inode(&entry->rule, f);
|
|
if (err)
|
|
goto exit_free;
|
|
break;
|
|
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;
|
|
case AUDIT_PERM:
|
|
if (f->val & ~15)
|
|
goto exit_free;
|
|
break;
|
|
case AUDIT_FILETYPE:
|
|
if ((f->val & ~S_IFMT) > S_IFMT)
|
|
goto exit_free;
|
|
break;
|
|
default:
|
|
goto exit_free;
|
|
}
|
|
}
|
|
|
|
if (entry->rule.inode_f && entry->rule.inode_f->op == Audit_not_equal)
|
|
entry->rule.inode_f = NULL;
|
|
|
|
exit_nofree:
|
|
return entry;
|
|
|
|
exit_free:
|
|
audit_free_rule(entry);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
/* Pack a filter field's string representation into data block. */
|
|
static inline size_t audit_pack_string(void **bufp, const char *str)
|
|
{
|
|
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;
|
|
|
|
rule = kzalloc(sizeof(*rule), GFP_KERNEL);
|
|
if (unlikely(!rule))
|
|
return NULL;
|
|
|
|
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] |= audit_ops[krule->fields[i].op];
|
|
}
|
|
}
|
|
for (i = 0; i < AUDIT_BITMASK_SIZE; i++) rule->mask[i] = krule->mask[i];
|
|
|
|
return rule;
|
|
}
|
|
|
|
/* 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))
|
|
return NULL;
|
|
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] = audit_ops[f->op];
|
|
switch(f->type) {
|
|
case AUDIT_SUBJ_USER:
|
|
case AUDIT_SUBJ_ROLE:
|
|
case AUDIT_SUBJ_TYPE:
|
|
case AUDIT_SUBJ_SEN:
|
|
case AUDIT_SUBJ_CLR:
|
|
case AUDIT_OBJ_USER:
|
|
case AUDIT_OBJ_ROLE:
|
|
case AUDIT_OBJ_TYPE:
|
|
case AUDIT_OBJ_LEV_LOW:
|
|
case AUDIT_OBJ_LEV_HIGH:
|
|
data->buflen += data->values[i] =
|
|
audit_pack_string(&bufp, f->lsm_str);
|
|
break;
|
|
case AUDIT_WATCH:
|
|
data->buflen += data->values[i] =
|
|
audit_pack_string(&bufp, krule->watch->path);
|
|
break;
|
|
case AUDIT_DIR:
|
|
data->buflen += data->values[i] =
|
|
audit_pack_string(&bufp,
|
|
audit_tree_path(krule->tree));
|
|
break;
|
|
case AUDIT_FILTERKEY:
|
|
data->buflen += data->values[i] =
|
|
audit_pack_string(&bufp, krule->filterkey);
|
|
break;
|
|
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)
|
|
return 1;
|
|
|
|
for (i = 0; i < a->field_count; i++) {
|
|
if (a->fields[i].type != b->fields[i].type ||
|
|
a->fields[i].op != b->fields[i].op)
|
|
return 1;
|
|
|
|
switch(a->fields[i].type) {
|
|
case AUDIT_SUBJ_USER:
|
|
case AUDIT_SUBJ_ROLE:
|
|
case AUDIT_SUBJ_TYPE:
|
|
case AUDIT_SUBJ_SEN:
|
|
case AUDIT_SUBJ_CLR:
|
|
case AUDIT_OBJ_USER:
|
|
case AUDIT_OBJ_ROLE:
|
|
case AUDIT_OBJ_TYPE:
|
|
case AUDIT_OBJ_LEV_LOW:
|
|
case AUDIT_OBJ_LEV_HIGH:
|
|
if (strcmp(a->fields[i].lsm_str, b->fields[i].lsm_str))
|
|
return 1;
|
|
break;
|
|
case AUDIT_WATCH:
|
|
if (strcmp(a->watch->path, b->watch->path))
|
|
return 1;
|
|
break;
|
|
case AUDIT_DIR:
|
|
if (strcmp(audit_tree_path(a->tree),
|
|
audit_tree_path(b->tree)))
|
|
return 1;
|
|
break;
|
|
case AUDIT_FILTERKEY:
|
|
/* both filterkeys exist based on above type compare */
|
|
if (strcmp(a->filterkey, b->filterkey))
|
|
return 1;
|
|
break;
|
|
default:
|
|
if (a->fields[i].val != b->fields[i].val)
|
|
return 1;
|
|
}
|
|
}
|
|
|
|
for (i = 0; i < AUDIT_BITMASK_SIZE; i++)
|
|
if (a->mask[i] != b->mask[i])
|
|
return 1;
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* 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 (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;
|
|
}
|
|
|
|
/* Duplicate LSM field information. The lsm_rule is opaque, so must be
|
|
* re-initialized. */
|
|
static inline int audit_dupe_lsm_field(struct audit_field *df,
|
|
struct audit_field *sf)
|
|
{
|
|
int ret = 0;
|
|
char *lsm_str;
|
|
|
|
/* our own copy of lsm_str */
|
|
lsm_str = kstrdup(sf->lsm_str, GFP_KERNEL);
|
|
if (unlikely(!lsm_str))
|
|
return -ENOMEM;
|
|
df->lsm_str = lsm_str;
|
|
|
|
/* our own (refreshed) copy of lsm_rule */
|
|
ret = security_audit_rule_init(df->type, df->op, df->lsm_str,
|
|
(void **)&df->lsm_rule);
|
|
/* Keep currently invalid fields around in case they
|
|
* become valid after a policy reload. */
|
|
if (ret == -EINVAL) {
|
|
printk(KERN_WARNING "audit rule for LSM \'%s\' is "
|
|
"invalid\n", df->lsm_str);
|
|
ret = 0;
|
|
}
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* Duplicate an audit rule. This will be a deep copy with the exception
|
|
* of the watch - that pointer is carried over. The LSM specific fields
|
|
* will be updated in the copy. The point is to be able to replace the old
|
|
* 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)
|
|
{
|
|
u32 fcount = old->field_count;
|
|
struct audit_entry *entry;
|
|
struct audit_krule *new;
|
|
char *fk;
|
|
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->prio = old->prio;
|
|
new->buflen = old->buflen;
|
|
new->inode_f = old->inode_f;
|
|
new->watch = NULL;
|
|
new->field_count = old->field_count;
|
|
/*
|
|
* 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;
|
|
memcpy(new->fields, old->fields, sizeof(struct audit_field) * fcount);
|
|
|
|
/* deep copy this information, updating the lsm_rule fields, because
|
|
* the originals will all be freed when the old rule is freed. */
|
|
for (i = 0; i < fcount; i++) {
|
|
switch (new->fields[i].type) {
|
|
case AUDIT_SUBJ_USER:
|
|
case AUDIT_SUBJ_ROLE:
|
|
case AUDIT_SUBJ_TYPE:
|
|
case AUDIT_SUBJ_SEN:
|
|
case AUDIT_SUBJ_CLR:
|
|
case AUDIT_OBJ_USER:
|
|
case AUDIT_OBJ_ROLE:
|
|
case AUDIT_OBJ_TYPE:
|
|
case AUDIT_OBJ_LEV_LOW:
|
|
case AUDIT_OBJ_LEV_HIGH:
|
|
err = audit_dupe_lsm_field(&new->fields[i],
|
|
&old->fields[i]);
|
|
break;
|
|
case AUDIT_FILTERKEY:
|
|
fk = kstrdup(old->filterkey, GFP_KERNEL);
|
|
if (unlikely(!fk))
|
|
err = -ENOMEM;
|
|
else
|
|
new->filterkey = fk;
|
|
}
|
|
if (err) {
|
|
audit_free_rule(entry);
|
|
return ERR_PTR(err);
|
|
}
|
|
}
|
|
|
|
if (watch) {
|
|
audit_get_watch(watch);
|
|
new->watch = watch;
|
|
}
|
|
|
|
return entry;
|
|
}
|
|
|
|
/* 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;
|
|
|
|
mutex_lock(&audit_filter_mutex);
|
|
list_for_each_entry_safe(owatch, nextw, &parent->watches, wlist) {
|
|
if (audit_compare_dname_path(dname, owatch->path, NULL))
|
|
continue;
|
|
|
|
/* If the update involves invalidating rules, do the inode-based
|
|
* filtering now, so we don't omit records. */
|
|
if (invalidating && current->audit_context)
|
|
audit_filter_inodes(current, current->audit_context);
|
|
|
|
nwatch = audit_dupe_watch(owatch);
|
|
if (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 (IS_ERR(nentry)) {
|
|
list_del(&oentry->rule.list);
|
|
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]);
|
|
list_replace(&oentry->rule.list,
|
|
&nentry->rule.list);
|
|
}
|
|
|
|
call_rcu(&oentry->rcu, audit_free_rule_rcu);
|
|
}
|
|
|
|
if (audit_enabled) {
|
|
struct audit_buffer *ab;
|
|
ab = audit_log_start(NULL, GFP_NOFS,
|
|
AUDIT_CONFIG_CHANGE);
|
|
audit_log_format(ab, "auid=%u ses=%u",
|
|
audit_get_loginuid(current),
|
|
audit_get_sessionid(current));
|
|
audit_log_format(ab,
|
|
" op=updated rules specifying path=");
|
|
audit_log_untrustedstring(ab, owatch->path);
|
|
audit_log_format(ab, " with dev=%u ino=%lu\n",
|
|
dev, ino);
|
|
audit_log_format(ab, " list=%d res=1", r->listnr);
|
|
audit_log_end(ab);
|
|
}
|
|
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);
|
|
if (audit_enabled) {
|
|
struct audit_buffer *ab;
|
|
ab = audit_log_start(NULL, GFP_NOFS,
|
|
AUDIT_CONFIG_CHANGE);
|
|
audit_log_format(ab, "auid=%u ses=%u",
|
|
audit_get_loginuid(current),
|
|
audit_get_sessionid(current));
|
|
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);
|
|
}
|
|
list_del(&r->rlist);
|
|
list_del(&r->list);
|
|
list_del_rcu(&e->list);
|
|
call_rcu(&e->rcu, audit_free_rule_rcu);
|
|
}
|
|
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 unpin matching the pin in audit_do_del_rule() */
|
|
unpin_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 **p)
|
|
{
|
|
struct audit_entry *e, *found = NULL;
|
|
struct list_head *list;
|
|
int h;
|
|
|
|
if (entry->rule.inode_f) {
|
|
h = audit_hash_ino(entry->rule.inode_f->val);
|
|
*p = list = &audit_inode_hash[h];
|
|
} else 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;
|
|
} else {
|
|
*p = list = &audit_filter_list[entry->rule.listnr];
|
|
}
|
|
|
|
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) {
|
|
path_put(&ndp->path);
|
|
kfree(ndp);
|
|
}
|
|
if (ndw) {
|
|
path_put(&ndw->path);
|
|
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) {
|
|
watch->dev = ndw->path.dentry->d_inode->i_sb->s_dev;
|
|
watch->ino = ndw->path.dentry->d_inode->i_ino;
|
|
}
|
|
|
|
/* 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);
|
|
|
|
if (inotify_find_watch(audit_ih, ndp->path.dentry->d_inode,
|
|
&i_watch) < 0) {
|
|
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;
|
|
}
|
|
|
|
static u64 prio_low = ~0ULL/2;
|
|
static u64 prio_high = ~0ULL/2 - 1;
|
|
|
|
/* Add rule to given filterlist if not a duplicate. */
|
|
static inline int audit_add_rule(struct audit_entry *entry)
|
|
{
|
|
struct audit_entry *e;
|
|
struct audit_watch *watch = entry->rule.watch;
|
|
struct audit_tree *tree = entry->rule.tree;
|
|
struct nameidata *ndp = NULL, *ndw = NULL;
|
|
struct list_head *list;
|
|
int h, err;
|
|
#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
|
|
|
|
mutex_lock(&audit_filter_mutex);
|
|
e = audit_find_rule(entry, &list);
|
|
mutex_unlock(&audit_filter_mutex);
|
|
if (e) {
|
|
err = -EEXIST;
|
|
/* normally audit_add_tree_rule() will free it on failure */
|
|
if (tree)
|
|
audit_put_tree(tree);
|
|
goto error;
|
|
}
|
|
|
|
/* Avoid calling path_lookup under audit_filter_mutex. */
|
|
if (watch) {
|
|
err = audit_get_nd(watch->path, &ndp, &ndw);
|
|
if (err)
|
|
goto error;
|
|
}
|
|
|
|
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];
|
|
}
|
|
if (tree) {
|
|
err = audit_add_tree_rule(&entry->rule);
|
|
if (err) {
|
|
mutex_unlock(&audit_filter_mutex);
|
|
goto error;
|
|
}
|
|
}
|
|
|
|
entry->rule.prio = ~0ULL;
|
|
if (entry->rule.listnr == AUDIT_FILTER_EXIT) {
|
|
if (entry->rule.flags & AUDIT_FILTER_PREPEND)
|
|
entry->rule.prio = ++prio_high;
|
|
else
|
|
entry->rule.prio = --prio_low;
|
|
}
|
|
|
|
if (entry->rule.flags & AUDIT_FILTER_PREPEND) {
|
|
list_add(&entry->rule.list,
|
|
&audit_rules_list[entry->rule.listnr]);
|
|
list_add_rcu(&entry->list, list);
|
|
entry->rule.flags &= ~AUDIT_FILTER_PREPEND;
|
|
} else {
|
|
list_add_tail(&entry->rule.list,
|
|
&audit_rules_list[entry->rule.listnr]);
|
|
list_add_tail_rcu(&entry->list, list);
|
|
}
|
|
#ifdef CONFIG_AUDITSYSCALL
|
|
if (!dont_count)
|
|
audit_n_rules++;
|
|
|
|
if (!audit_match_signal(entry))
|
|
audit_signals++;
|
|
#endif
|
|
mutex_unlock(&audit_filter_mutex);
|
|
|
|
audit_put_nd(ndp, ndw); /* NULL args OK */
|
|
return 0;
|
|
|
|
error:
|
|
audit_put_nd(ndp, ndw); /* NULL args OK */
|
|
if (watch)
|
|
audit_put_watch(watch); /* tmp watch, matches initial get */
|
|
return err;
|
|
}
|
|
|
|
/* Remove an existing rule from filterlist. */
|
|
static inline int audit_del_rule(struct audit_entry *entry)
|
|
{
|
|
struct audit_entry *e;
|
|
struct audit_watch *watch, *tmp_watch = entry->rule.watch;
|
|
struct audit_tree *tree = entry->rule.tree;
|
|
struct list_head *list;
|
|
LIST_HEAD(inotify_list);
|
|
int ret = 0;
|
|
#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
|
|
|
|
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().
|
|
* If filesystem is going away, just leave
|
|
* the sucker alone, eviction will take
|
|
* care of it.
|
|
*/
|
|
if (pin_inotify_watch(&parent->wdata))
|
|
list_add(&parent->ilist, &inotify_list);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (e->rule.tree)
|
|
audit_remove_tree_rule(&e->rule);
|
|
|
|
list_del_rcu(&e->list);
|
|
list_del(&e->rule.list);
|
|
call_rcu(&e->rcu, audit_free_rule_rcu);
|
|
|
|
#ifdef CONFIG_AUDITSYSCALL
|
|
if (!dont_count)
|
|
audit_n_rules--;
|
|
|
|
if (!audit_match_signal(entry))
|
|
audit_signals--;
|
|
#endif
|
|
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 */
|
|
if (tree)
|
|
audit_put_tree(tree); /* that's the temporary one */
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* List rules using struct audit_rule. Exists for backward
|
|
* compatibility with userspace. */
|
|
static void audit_list(int pid, int seq, struct sk_buff_head *q)
|
|
{
|
|
struct sk_buff *skb;
|
|
struct audit_krule *r;
|
|
int i;
|
|
|
|
/* This is a blocking read, so use audit_filter_mutex instead of rcu
|
|
* iterator to sync with list writers. */
|
|
for (i=0; i<AUDIT_NR_FILTERS; i++) {
|
|
list_for_each_entry(r, &audit_rules_list[i], list) {
|
|
struct audit_rule *rule;
|
|
|
|
rule = audit_krule_to_rule(r);
|
|
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);
|
|
}
|
|
}
|
|
skb = audit_make_reply(pid, seq, AUDIT_LIST, 1, 1, NULL, 0);
|
|
if (skb)
|
|
skb_queue_tail(q, skb);
|
|
}
|
|
|
|
/* List rules using struct audit_rule_data. */
|
|
static void audit_list_rules(int pid, int seq, struct sk_buff_head *q)
|
|
{
|
|
struct sk_buff *skb;
|
|
struct audit_krule *r;
|
|
int i;
|
|
|
|
/* This is a blocking read, so use audit_filter_mutex instead of rcu
|
|
* iterator to sync with list writers. */
|
|
for (i=0; i<AUDIT_NR_FILTERS; i++) {
|
|
list_for_each_entry(r, &audit_rules_list[i], list) {
|
|
struct audit_rule_data *data;
|
|
|
|
data = audit_krule_to_data(r);
|
|
if (unlikely(!data))
|
|
break;
|
|
skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 0, 1,
|
|
data, sizeof(*data) + data->buflen);
|
|
if (skb)
|
|
skb_queue_tail(q, skb);
|
|
kfree(data);
|
|
}
|
|
}
|
|
skb = audit_make_reply(pid, seq, AUDIT_LIST_RULES, 1, 1, NULL, 0);
|
|
if (skb)
|
|
skb_queue_tail(q, skb);
|
|
}
|
|
|
|
/* Log rule additions and removals */
|
|
static void audit_log_rule_change(uid_t loginuid, u32 sessionid, u32 sid,
|
|
char *action, struct audit_krule *rule,
|
|
int res)
|
|
{
|
|
struct audit_buffer *ab;
|
|
|
|
if (!audit_enabled)
|
|
return;
|
|
|
|
ab = audit_log_start(NULL, GFP_KERNEL, AUDIT_CONFIG_CHANGE);
|
|
if (!ab)
|
|
return;
|
|
audit_log_format(ab, "auid=%u ses=%u", loginuid, sessionid);
|
|
if (sid) {
|
|
char *ctx = NULL;
|
|
u32 len;
|
|
if (security_secid_to_secctx(sid, &ctx, &len))
|
|
audit_log_format(ab, " ssid=%u", sid);
|
|
else {
|
|
audit_log_format(ab, " subj=%s", ctx);
|
|
security_release_secctx(ctx, len);
|
|
}
|
|
}
|
|
audit_log_format(ab, " op=%s rule key=", action);
|
|
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);
|
|
}
|
|
|
|
/**
|
|
* 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
|
|
* @datasz: size of payload data
|
|
* @loginuid: loginuid of sender
|
|
* @sessionid: sessionid for netlink audit message
|
|
* @sid: SE Linux Security ID of sender
|
|
*/
|
|
int audit_receive_filter(int type, int pid, int uid, int seq, void *data,
|
|
size_t datasz, uid_t loginuid, u32 sessionid, u32 sid)
|
|
{
|
|
struct task_struct *tsk;
|
|
struct audit_netlink_list *dest;
|
|
int err = 0;
|
|
struct audit_entry *entry;
|
|
|
|
switch (type) {
|
|
case AUDIT_LIST:
|
|
case AUDIT_LIST_RULES:
|
|
/* 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 */
|
|
|
|
dest = kmalloc(sizeof(struct audit_netlink_list), GFP_KERNEL);
|
|
if (!dest)
|
|
return -ENOMEM;
|
|
dest->pid = pid;
|
|
skb_queue_head_init(&dest->q);
|
|
|
|
mutex_lock(&audit_filter_mutex);
|
|
if (type == AUDIT_LIST)
|
|
audit_list(pid, seq, &dest->q);
|
|
else
|
|
audit_list_rules(pid, seq, &dest->q);
|
|
mutex_unlock(&audit_filter_mutex);
|
|
|
|
tsk = kthread_run(audit_send_list, dest, "audit_send_list");
|
|
if (IS_ERR(tsk)) {
|
|
skb_queue_purge(&dest->q);
|
|
kfree(dest);
|
|
err = PTR_ERR(tsk);
|
|
}
|
|
break;
|
|
case AUDIT_ADD:
|
|
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_log_rule_change(loginuid, sessionid, sid, "add",
|
|
&entry->rule, !err);
|
|
|
|
if (err)
|
|
audit_free_rule(entry);
|
|
break;
|
|
case AUDIT_DEL:
|
|
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_log_rule_change(loginuid, sessionid, sid, "remove",
|
|
&entry->rule, !err);
|
|
|
|
audit_free_rule(entry);
|
|
break;
|
|
default:
|
|
return -EINVAL;
|
|
}
|
|
|
|
return err;
|
|
}
|
|
|
|
int audit_comparator(u32 left, u32 op, u32 right)
|
|
{
|
|
switch (op) {
|
|
case Audit_equal:
|
|
return (left == right);
|
|
case Audit_not_equal:
|
|
return (left != right);
|
|
case Audit_lt:
|
|
return (left < right);
|
|
case Audit_le:
|
|
return (left <= right);
|
|
case Audit_gt:
|
|
return (left > right);
|
|
case Audit_ge:
|
|
return (left >= right);
|
|
case Audit_bitmask:
|
|
return (left & right);
|
|
case Audit_bittest:
|
|
return ((left & right) == right);
|
|
default:
|
|
BUG();
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
/* Compare given dentry name with last component in given path,
|
|
* return of 0 indicates a match. */
|
|
int audit_compare_dname_path(const char *dname, const char *path,
|
|
int *dirlen)
|
|
{
|
|
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++;
|
|
}
|
|
|
|
/* return length of path's directory component */
|
|
if (dirlen)
|
|
*dirlen = p - path;
|
|
return strncmp(p, dname, dlen);
|
|
}
|
|
|
|
static int audit_filter_user_rules(struct netlink_skb_parms *cb,
|
|
struct audit_krule *rule,
|
|
enum audit_state *state)
|
|
{
|
|
int i;
|
|
|
|
for (i = 0; i < rule->field_count; i++) {
|
|
struct audit_field *f = &rule->fields[i];
|
|
int result = 0;
|
|
|
|
switch (f->type) {
|
|
case AUDIT_PID:
|
|
result = audit_comparator(cb->creds.pid, f->op, f->val);
|
|
break;
|
|
case AUDIT_UID:
|
|
result = audit_comparator(cb->creds.uid, f->op, f->val);
|
|
break;
|
|
case AUDIT_GID:
|
|
result = audit_comparator(cb->creds.gid, f->op, f->val);
|
|
break;
|
|
case AUDIT_LOGINUID:
|
|
result = audit_comparator(cb->loginuid, f->op, f->val);
|
|
break;
|
|
}
|
|
|
|
if (!result)
|
|
return 0;
|
|
}
|
|
switch (rule->action) {
|
|
case AUDIT_NEVER: *state = AUDIT_DISABLED; break;
|
|
case AUDIT_ALWAYS: *state = AUDIT_RECORD_CONTEXT; break;
|
|
}
|
|
return 1;
|
|
}
|
|
|
|
int audit_filter_user(struct netlink_skb_parms *cb)
|
|
{
|
|
enum audit_state state = AUDIT_DISABLED;
|
|
struct audit_entry *e;
|
|
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;
|
|
|
|
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) {
|
|
int i;
|
|
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);
|
|
if (!result)
|
|
break;
|
|
}
|
|
}
|
|
if (result)
|
|
goto unlock_and_return;
|
|
}
|
|
unlock_and_return:
|
|
rcu_read_unlock();
|
|
return result;
|
|
}
|
|
|
|
static int update_lsm_rule(struct audit_krule *r)
|
|
{
|
|
struct audit_entry *entry = container_of(r, struct audit_entry, rule);
|
|
struct audit_entry *nentry;
|
|
struct audit_watch *watch;
|
|
struct audit_tree *tree;
|
|
int err = 0;
|
|
|
|
if (!security_audit_rule_known(r))
|
|
return 0;
|
|
|
|
watch = r->watch;
|
|
tree = r->tree;
|
|
nentry = audit_dupe_rule(r, watch);
|
|
if (IS_ERR(nentry)) {
|
|
/* save the first error encountered for the
|
|
* return value */
|
|
err = PTR_ERR(nentry);
|
|
audit_panic("error updating LSM filters");
|
|
if (watch)
|
|
list_del(&r->rlist);
|
|
list_del_rcu(&entry->list);
|
|
list_del(&r->list);
|
|
} else {
|
|
if (watch) {
|
|
list_add(&nentry->rule.rlist, &watch->rules);
|
|
list_del(&r->rlist);
|
|
} else if (tree)
|
|
list_replace_init(&r->rlist, &nentry->rule.rlist);
|
|
list_replace_rcu(&entry->list, &nentry->list);
|
|
list_replace(&r->list, &nentry->rule.list);
|
|
}
|
|
call_rcu(&entry->rcu, audit_free_rule_rcu);
|
|
|
|
return err;
|
|
}
|
|
|
|
/* This function will re-initialize the lsm_rule field of all applicable rules.
|
|
* It will traverse the filter lists serarching for rules that contain LSM
|
|
* specific filter fields. When such a rule is found, it is copied, the
|
|
* LSM field is re-initialized, and the old rule is replaced with the
|
|
* updated rule. */
|
|
int audit_update_lsm_rules(void)
|
|
{
|
|
struct audit_krule *r, *n;
|
|
int i, err = 0;
|
|
|
|
/* audit_filter_mutex synchronizes the writers */
|
|
mutex_lock(&audit_filter_mutex);
|
|
|
|
for (i = 0; i < AUDIT_NR_FILTERS; i++) {
|
|
list_for_each_entry_safe(r, n, &audit_rules_list[i], list) {
|
|
int res = update_lsm_rule(r);
|
|
if (!err)
|
|
err = res;
|
|
}
|
|
}
|
|
mutex_unlock(&audit_filter_mutex);
|
|
|
|
return err;
|
|
}
|
|
|
|
/* 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);
|
|
}
|