diff options
| -rw-r--r-- | kernel/Makefile | 2 | ||||
| -rw-r--r-- | kernel/audit.h | 14 | ||||
| -rw-r--r-- | kernel/audit_fsnotify.c | 216 | ||||
| -rw-r--r-- | kernel/auditfilter.c | 2 |
4 files changed, 232 insertions, 2 deletions
diff --git a/kernel/Makefile b/kernel/Makefile index 1408b3353a3c..d7657f5535c9 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -62,7 +62,7 @@ obj-$(CONFIG_SMP) += stop_machine.o obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o obj-$(CONFIG_AUDIT) += audit.o auditfilter.o obj-$(CONFIG_AUDITSYSCALL) += auditsc.o -obj-$(CONFIG_AUDIT_WATCH) += audit_watch.o +obj-$(CONFIG_AUDIT_WATCH) += audit_watch.o audit_fsnotify.o obj-$(CONFIG_AUDIT_TREE) += audit_tree.o obj-$(CONFIG_GCOV_KERNEL) += gcov/ obj-$(CONFIG_KPROBES) += kprobes.o diff --git a/kernel/audit.h b/kernel/audit.h index 1caa0d345d90..7102d538737b 100644 --- a/kernel/audit.h +++ b/kernel/audit.h @@ -50,6 +50,7 @@ enum audit_state { /* Rule lists */ struct audit_watch; +struct audit_fsnotify_mark; struct audit_tree; struct audit_chunk; @@ -252,6 +253,7 @@ struct audit_net { extern int selinux_audit_rule_update(void); extern struct mutex audit_filter_mutex; +extern int audit_del_rule(struct audit_entry *); extern void audit_free_rule_rcu(struct rcu_head *); extern struct list_head audit_filter_list[]; @@ -266,6 +268,13 @@ extern int audit_add_watch(struct audit_krule *krule, struct list_head **list); extern void audit_remove_watch_rule(struct audit_krule *krule); extern char *audit_watch_path(struct audit_watch *watch); extern int audit_watch_compare(struct audit_watch *watch, unsigned long ino, dev_t dev); + +extern struct audit_fsnotify_mark *audit_alloc_mark(struct audit_krule *krule, char *pathname, int len); +extern char *audit_mark_path(struct audit_fsnotify_mark *mark); +extern void audit_remove_mark(struct audit_fsnotify_mark *audit_mark); +extern void audit_remove_mark_rule(struct audit_krule *krule); +extern int audit_mark_compare(struct audit_fsnotify_mark *mark, unsigned long ino, dev_t dev); + #else #define audit_put_watch(w) {} #define audit_get_watch(w) {} @@ -275,6 +284,11 @@ extern int audit_watch_compare(struct audit_watch *watch, unsigned long ino, dev #define audit_watch_path(w) "" #define audit_watch_compare(w, i, d) 0 +#define audit_alloc_mark(k, p, l) (ERR_PTR(-EINVAL)) +#define audit_mark_path(m) "" +#define audit_remove_mark(m) +#define audit_remove_mark_rule(k) +#define audit_mark_compare(m, i, d) 0 #endif /* CONFIG_AUDIT_WATCH */ #ifdef CONFIG_AUDIT_TREE diff --git a/kernel/audit_fsnotify.c b/kernel/audit_fsnotify.c new file mode 100644 index 000000000000..27c6046c2c3d --- /dev/null +++ b/kernel/audit_fsnotify.c @@ -0,0 +1,216 @@ +/* audit_fsnotify.c -- tracking inodes + * + * Copyright 2003-2009,2014-2015 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. + */ + +#include <linux/kernel.h> +#include <linux/audit.h> +#include <linux/kthread.h> +#include <linux/mutex.h> +#include <linux/fs.h> +#include <linux/fsnotify_backend.h> +#include <linux/namei.h> +#include <linux/netlink.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/security.h> +#include "audit.h" + +/* + * this mark lives on the parent directory of the inode in question. + * but dev, ino, and path are about the child + */ +struct audit_fsnotify_mark { + dev_t dev; /* associated superblock device */ + unsigned long ino; /* associated inode number */ + char *path; /* insertion path */ + struct fsnotify_mark mark; /* fsnotify mark on the inode */ + struct audit_krule *rule; +}; + +/* fsnotify handle. */ +static struct fsnotify_group *audit_fsnotify_group; + +/* fsnotify events we care about. */ +#define AUDIT_FS_EVENTS (FS_MOVE | FS_CREATE | FS_DELETE | FS_DELETE_SELF |\ + FS_MOVE_SELF | FS_EVENT_ON_CHILD) + +static void audit_fsnotify_mark_free(struct audit_fsnotify_mark *audit_mark) +{ + kfree(audit_mark->path); + kfree(audit_mark); +} + +static void audit_fsnotify_free_mark(struct fsnotify_mark *mark) +{ + struct audit_fsnotify_mark *audit_mark; + + audit_mark = container_of(mark, struct audit_fsnotify_mark, mark); + audit_fsnotify_mark_free(audit_mark); +} + +char *audit_mark_path(struct audit_fsnotify_mark *mark) +{ + return mark->path; +} + +int audit_mark_compare(struct audit_fsnotify_mark *mark, unsigned long ino, dev_t dev) +{ + if (mark->ino == AUDIT_INO_UNSET) + return 0; + return (mark->ino == ino) && (mark->dev == dev); +} + +static void audit_update_mark(struct audit_fsnotify_mark *audit_mark, + struct inode *inode) +{ + audit_mark->dev = inode ? inode->i_sb->s_dev : AUDIT_DEV_UNSET; + audit_mark->ino = inode ? inode->i_ino : AUDIT_INO_UNSET; +} + +struct audit_fsnotify_mark *audit_alloc_mark(struct audit_krule *krule, char *pathname, int len) +{ + struct audit_fsnotify_mark *audit_mark; + struct path path; + struct dentry *dentry; + struct inode *inode; + int ret; + + if (pathname[0] != '/' || pathname[len-1] == '/') + return ERR_PTR(-EINVAL); + + dentry = kern_path_locked(pathname, &path); + if (IS_ERR(dentry)) + return (void *)dentry; /* returning an error */ + inode = path.dentry->d_inode; + mutex_unlock(&inode->i_mutex); + + audit_mark = kzalloc(sizeof(*audit_mark), GFP_KERNEL); + if (unlikely(!audit_mark)) { + audit_mark = ERR_PTR(-ENOMEM); + goto out; + } + + fsnotify_init_mark(&audit_mark->mark, audit_fsnotify_free_mark); + audit_mark->mark.mask = AUDIT_FS_EVENTS; + audit_mark->path = pathname; + audit_update_mark(audit_mark, dentry->d_inode); + audit_mark->rule = krule; + + ret = fsnotify_add_mark(&audit_mark->mark, audit_fsnotify_group, inode, NULL, true); + if (ret < 0) { + audit_fsnotify_mark_free(audit_mark); + audit_mark = ERR_PTR(ret); + } +out: + dput(dentry); + path_put(&path); + return audit_mark; +} + +static void audit_mark_log_rule_change(struct audit_fsnotify_mark *audit_mark, char *op) +{ + struct audit_buffer *ab; + struct audit_krule *rule = audit_mark->rule; + + if (!audit_enabled) + return; + ab = audit_log_start(NULL, GFP_NOFS, AUDIT_CONFIG_CHANGE); + if (unlikely(!ab)) + return; + audit_log_format(ab, "auid=%u ses=%u op=", + from_kuid(&init_user_ns, audit_get_loginuid(current)), + audit_get_sessionid(current)); + audit_log_string(ab, op); + audit_log_format(ab, " path="); + audit_log_untrustedstring(ab, audit_mark->path); + audit_log_key(ab, rule->filterkey); + audit_log_format(ab, " list=%d res=1", rule->listnr); + audit_log_end(ab); +} + +void audit_remove_mark(struct audit_fsnotify_mark *audit_mark) +{ + fsnotify_destroy_mark(&audit_mark->mark, audit_fsnotify_group); + fsnotify_put_mark(&audit_mark->mark); +} + +void audit_remove_mark_rule(struct audit_krule *krule) +{ + struct audit_fsnotify_mark *mark = krule->exe; + + audit_remove_mark(mark); +} + +static void audit_autoremove_mark_rule(struct audit_fsnotify_mark *audit_mark) +{ + struct audit_krule *rule = audit_mark->rule; + struct audit_entry *entry = container_of(rule, struct audit_entry, rule); + + audit_mark_log_rule_change(audit_mark, "autoremove_rule"); + audit_del_rule(entry); +} + +/* Update mark data in audit rules based on fsnotify events. */ +static int audit_mark_handle_event(struct fsnotify_group *group, + struct inode *to_tell, + struct fsnotify_mark *inode_mark, + struct fsnotify_mark *vfsmount_mark, + u32 mask, void *data, int data_type, + const unsigned char *dname, u32 cookie) +{ + struct audit_fsnotify_mark *audit_mark; + struct inode *inode = NULL; + + audit_mark = container_of(inode_mark, struct audit_fsnotify_mark, mark); + + BUG_ON(group != audit_fsnotify_group); + + switch (data_type) { + case (FSNOTIFY_EVENT_PATH): + inode = ((struct path *)data)->dentry->d_inode; + break; + case (FSNOTIFY_EVENT_INODE): + inode = (struct inode *)data; + break; + default: + BUG(); + return 0; + }; + + if (mask & (FS_CREATE|FS_MOVED_TO|FS_DELETE|FS_MOVED_FROM)) { + if (audit_compare_dname_path(dname, audit_mark->path, AUDIT_NAME_FULL)) + return 0; + audit_update_mark(audit_mark, inode); + } else if (mask & (FS_DELETE_SELF|FS_UNMOUNT|FS_MOVE_SELF)) + audit_autoremove_mark_rule(audit_mark); + + return 0; +} + +static const struct fsnotify_ops audit_mark_fsnotify_ops = { + .handle_event = audit_mark_handle_event, +}; + +static int __init audit_fsnotify_init(void) +{ + audit_fsnotify_group = fsnotify_alloc_group(&audit_mark_fsnotify_ops); + if (IS_ERR(audit_fsnotify_group)) { + audit_fsnotify_group = NULL; + audit_panic("cannot create audit fsnotify group"); + } + return 0; +} +device_initcall(audit_fsnotify_init); diff --git a/kernel/auditfilter.c b/kernel/auditfilter.c index 7ca7d3b5aca2..b4d8c366ec30 100644 --- a/kernel/auditfilter.c +++ b/kernel/auditfilter.c @@ -935,7 +935,7 @@ static inline int audit_add_rule(struct audit_entry *entry) } /* Remove an existing rule from filterlist. */ -static inline int audit_del_rule(struct audit_entry *entry) +int audit_del_rule(struct audit_entry *entry) { struct audit_entry *e; struct audit_tree *tree = entry->rule.tree; |