Merge tag 'audit-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit

Pull audit updates from Paul Moore:
 "Aside from some smaller bug fixes, here are the highlights:

   - add a new backlog wait metric to the audit status message, this is
     intended to help admins determine how long processes have been
     waiting for the audit backlog queue to clear

   - generate audit records for nftables configuration changes

   - generate CWD audit records for for the relevant LSM audit records"

* tag 'audit-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
  audit: report audit wait metric in audit status reply
  audit: purge audit_log_string from the intra-kernel audit API
  audit: issue CWD record to accompany LSM_AUDIT_DATA_* records
  audit: use the proper gfp flags in the audit_log_nfcfg() calls
  audit: remove unused !CONFIG_AUDITSYSCALL __audit_inode* stubs
  audit: add gfp parameter to audit_log_nfcfg
  audit: log nftables configuration change events
  audit: Use struct_size() helper in alloc_chunk

Author: torvalds

include/linux/audit.h

@@ -12,6 +12,7 @@
 #include <linux/sched.h>
 #include <linux/ptrace.h>
 #include <uapi/linux/audit.h>
+#include <uapi/linux/netfilter/nf_tables.h>
 
 #define AUDIT_INO_UNSET ((unsigned long)-1)
 #define AUDIT_DEV_UNSET ((dev_t)-1)
@@ -98,6 +99,23 @@ enum audit_nfcfgop {
 	AUDIT_XT_OP_REGISTER,
 	AUDIT_XT_OP_REPLACE,
 	AUDIT_XT_OP_UNREGISTER,
+	AUDIT_NFT_OP_TABLE_REGISTER,
+	AUDIT_NFT_OP_TABLE_UNREGISTER,
+	AUDIT_NFT_OP_CHAIN_REGISTER,
+	AUDIT_NFT_OP_CHAIN_UNREGISTER,
+	AUDIT_NFT_OP_RULE_REGISTER,
+	AUDIT_NFT_OP_RULE_UNREGISTER,
+	AUDIT_NFT_OP_SET_REGISTER,
+	AUDIT_NFT_OP_SET_UNREGISTER,
+	AUDIT_NFT_OP_SETELEM_REGISTER,
+	AUDIT_NFT_OP_SETELEM_UNREGISTER,
+	AUDIT_NFT_OP_GEN_REGISTER,
+	AUDIT_NFT_OP_OBJ_REGISTER,
+	AUDIT_NFT_OP_OBJ_UNREGISTER,
+	AUDIT_NFT_OP_OBJ_RESET,
+	AUDIT_NFT_OP_FLOWTABLE_REGISTER,
+	AUDIT_NFT_OP_FLOWTABLE_UNREGISTER,
+	AUDIT_NFT_OP_INVALID,
 };
 
 extern int is_audit_feature_set(int which);
@@ -274,7 +292,7 @@ extern void __audit_syscall_entry(int major, unsigned long a0, unsigned long a1,
 extern void __audit_syscall_exit(int ret_success, long ret_value);
 extern struct filename *__audit_reusename(const __user char *uptr);
 extern void __audit_getname(struct filename *name);
-
+extern void __audit_getcwd(void);
 extern void __audit_inode(struct filename *name, const struct dentry *dentry,
 				unsigned int flags);
 extern void __audit_file(const struct file *);
@@ -333,6 +351,11 @@ static inline void audit_getname(struct filename *name)
 	if (unlikely(!audit_dummy_context()))
 		__audit_getname(name);
 }
+static inline void audit_getcwd(void)
+{
+	if (unlikely(audit_context()))
+		__audit_getcwd();
+}
 static inline void audit_inode(struct filename *name,
 				const struct dentry *dentry,
 				unsigned int aflags) {
@@ -386,7 +409,7 @@ extern void __audit_fanotify(unsigned int response);
 extern void __audit_tk_injoffset(struct timespec64 offset);
 extern void __audit_ntp_log(const struct audit_ntp_data *ad);
 extern void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries,
-			      enum audit_nfcfgop op);
+			      enum audit_nfcfgop op, gfp_t gfp);
 
 static inline void audit_ipc_obj(struct kern_ipc_perm *ipcp)
 {
@@ -524,10 +547,10 @@ static inline void audit_ntp_log(const struct audit_ntp_data *ad)
 
 static inline void audit_log_nfcfg(const char *name, u8 af,
 				   unsigned int nentries,
-				   enum audit_nfcfgop op)
+				   enum audit_nfcfgop op, gfp_t gfp)
 {
 	if (audit_enabled)
-		__audit_log_nfcfg(name, af, nentries, op);
+		__audit_log_nfcfg(name, af, nentries, op, gfp);
 }
 
 extern int audit_n_rules;
@@ -561,13 +584,7 @@ static inline struct filename *audit_reusename(const __user char *name)
 }
 static inline void audit_getname(struct filename *name)
 { }
-static inline void __audit_inode(struct filename *name,
-					const struct dentry *dentry,
-					unsigned int flags)
-{ }
-static inline void __audit_inode_child(struct inode *parent,
-					const struct dentry *dentry,
-					const unsigned char type)
+static inline void audit_getcwd(void)
 { }
 static inline void audit_inode(struct filename *name,
 				const struct dentry *dentry,
@@ -665,7 +682,7 @@ static inline void audit_ptrace(struct task_struct *t)
 
 static inline void audit_log_nfcfg(const char *name, u8 af,
 				   unsigned int nentries,
-				   enum audit_nfcfgop op)
+				   enum audit_nfcfgop op, gfp_t gfp)
 { }
 
 #define audit_n_rules 0
@@ -677,9 +694,4 @@ static inline bool audit_loginuid_set(struct task_struct *tsk)
 	return uid_valid(audit_get_loginuid(tsk));
 }
 
-static inline void audit_log_string(struct audit_buffer *ab, const char *buf)
-{
-	audit_log_n_string(ab, buf, strlen(buf));
-}
-
 #endif

include/uapi/linux/audit.h

@@ -333,14 +333,15 @@ enum {
 };
 
 /* Status symbols */
-				/* Mask values */
-#define AUDIT_STATUS_ENABLED		0x0001
-#define AUDIT_STATUS_FAILURE		0x0002
-#define AUDIT_STATUS_PID		0x0004
+						/* Mask values */
+#define AUDIT_STATUS_ENABLED			0x0001
+#define AUDIT_STATUS_FAILURE			0x0002
+#define AUDIT_STATUS_PID			0x0004
 #define AUDIT_STATUS_RATE_LIMIT		0x0008
-#define AUDIT_STATUS_BACKLOG_LIMIT	0x0010
-#define AUDIT_STATUS_BACKLOG_WAIT_TIME	0x0020
-#define AUDIT_STATUS_LOST		0x0040
+#define AUDIT_STATUS_BACKLOG_LIMIT		0x0010
+#define AUDIT_STATUS_BACKLOG_WAIT_TIME		0x0020
+#define AUDIT_STATUS_LOST			0x0040
+#define AUDIT_STATUS_BACKLOG_WAIT_TIME_ACTUAL	0x0080
 
 #define AUDIT_FEATURE_BITMAP_BACKLOG_LIMIT	0x00000001
 #define AUDIT_FEATURE_BITMAP_BACKLOG_WAIT_TIME	0x00000002
@@ -467,6 +468,9 @@ struct audit_status {
 		__u32	feature_bitmap;	/* bitmap of kernel audit features */
 	};
 	__u32		backlog_wait_time;/* message queue wait timeout */
+	__u32           backlog_wait_time_actual;/* time spent waiting while
+						  * message limit exceeded
+						  */
 };
 
 struct audit_features {

kernel/audit.c

@@ -136,6 +136,11 @@ u32		audit_sig_sid = 0;
 */
 static atomic_t	audit_lost = ATOMIC_INIT(0);
 
+/* Monotonically increasing sum of time the kernel has spent
+ * waiting while the backlog limit is exceeded.
+ */
+static atomic_t audit_backlog_wait_time_actual = ATOMIC_INIT(0);
+
 /* Hash for inode-based rules */
 struct list_head audit_inode_hash[AUDIT_INODE_BUCKETS];
 
@@ -1201,17 +1206,18 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 	case AUDIT_GET: {
 		struct audit_status	s;
 		memset(&s, 0, sizeof(s));
-		s.enabled		= audit_enabled;
-		s.failure		= audit_failure;
+		s.enabled		   = audit_enabled;
+		s.failure		   = audit_failure;
 		/* NOTE: use pid_vnr() so the PID is relative to the current
 		 *       namespace */
-		s.pid			= auditd_pid_vnr();
-		s.rate_limit		= audit_rate_limit;
-		s.backlog_limit		= audit_backlog_limit;
-		s.lost			= atomic_read(&audit_lost);
-		s.backlog		= skb_queue_len(&audit_queue);
-		s.feature_bitmap	= AUDIT_FEATURE_BITMAP_ALL;
-		s.backlog_wait_time	= audit_backlog_wait_time;
+		s.pid			   = auditd_pid_vnr();
+		s.rate_limit		   = audit_rate_limit;
+		s.backlog_limit		   = audit_backlog_limit;
+		s.lost			   = atomic_read(&audit_lost);
+		s.backlog		   = skb_queue_len(&audit_queue);
+		s.feature_bitmap	   = AUDIT_FEATURE_BITMAP_ALL;
+		s.backlog_wait_time	   = audit_backlog_wait_time;
+		s.backlog_wait_time_actual = atomic_read(&audit_backlog_wait_time_actual);
 		audit_send_reply(skb, seq, AUDIT_GET, 0, 0, &s, sizeof(s));
 		break;
 	}
@@ -1315,6 +1321,12 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
 			audit_log_config_change("lost", 0, lost, 1);
 			return lost;
 		}
+		if (s.mask == AUDIT_STATUS_BACKLOG_WAIT_TIME_ACTUAL) {
+			u32 actual = atomic_xchg(&audit_backlog_wait_time_actual, 0);
+
+			audit_log_config_change("backlog_wait_time_actual", 0, actual, 1);
+			return actual;
+		}
 		break;
 	}
 	case AUDIT_GET_FEATURE:
@@ -1826,12 +1838,15 @@ struct audit_buffer *audit_log_start(struct audit_context *ctx, gfp_t gfp_mask,
 			/* sleep if we are allowed and we haven't exhausted our
 			 * backlog wait limit */
 			if (gfpflags_allow_blocking(gfp_mask) && (stime > 0)) {
+				long rtime = stime;
+
 				DECLARE_WAITQUEUE(wait, current);
 
 				add_wait_queue_exclusive(&audit_backlog_wait,
 							 &wait);
 				set_current_state(TASK_UNINTERRUPTIBLE);
-				stime = schedule_timeout(stime);
+				stime = schedule_timeout(rtime);
+				atomic_add(rtime - stime, &audit_backlog_wait_time_actual);
 				remove_wait_queue(&audit_backlog_wait, &wait);
 			} else {
 				if (audit_rate_check() && printk_ratelimit())
@@ -2079,13 +2094,13 @@ void audit_log_d_path(struct audit_buffer *ab, const char *prefix,
 	/* We will allow 11 spaces for ' (deleted)' to be appended */
 	pathname = kmalloc(PATH_MAX+11, ab->gfp_mask);
 	if (!pathname) {
-		audit_log_string(ab, "<no_memory>");
+		audit_log_format(ab, "\"<no_memory>\"");
 		return;
 	}
 	p = d_path(path, pathname, PATH_MAX+11);
 	if (IS_ERR(p)) { /* Should never happen since we send PATH_MAX */
 		/* FIXME: can we save some information here? */
-		audit_log_string(ab, "<too_long>");
+		audit_log_format(ab, "\"<too_long>\"");
 	} else
 		audit_log_untrustedstring(ab, p);
 	kfree(pathname);

kernel/audit_tree.c

@@ -188,11 +188,9 @@ static struct fsnotify_mark *alloc_mark(void)
 static struct audit_chunk *alloc_chunk(int count)
 {
 	struct audit_chunk *chunk;
-	size_t size;
 	int i;
 
-	size = offsetof(struct audit_chunk, owners) + count * sizeof(struct node);
-	chunk = kzalloc(size, GFP_KERNEL);
+	chunk = kzalloc(struct_size(chunk, owners, count), GFP_KERNEL);
 	if (!chunk)
 		return NULL;
 

kernel/auditsc.c

@@ -75,6 +75,7 @@
 #include <linux/uaccess.h>
 #include <linux/fsnotify_backend.h>
 #include <uapi/linux/limits.h>
+#include <uapi/linux/netfilter/nf_tables.h>
 
 #include "audit.h"
 
@@ -136,9 +137,26 @@ struct audit_nfcfgop_tab {
 };
 
 static const struct audit_nfcfgop_tab audit_nfcfgs[] = {
-	{ AUDIT_XT_OP_REGISTER,		"register"	},
-	{ AUDIT_XT_OP_REPLACE,		"replace"	},
-	{ AUDIT_XT_OP_UNREGISTER,	"unregister"	},
+	{ AUDIT_XT_OP_REGISTER,			"xt_register"		   },
+	{ AUDIT_XT_OP_REPLACE,			"xt_replace"		   },
+	{ AUDIT_XT_OP_UNREGISTER,		"xt_unregister"		   },
+	{ AUDIT_NFT_OP_TABLE_REGISTER,		"nft_register_table"	   },
+	{ AUDIT_NFT_OP_TABLE_UNREGISTER,	"nft_unregister_table"	   },
+	{ AUDIT_NFT_OP_CHAIN_REGISTER,		"nft_register_chain"	   },
+	{ AUDIT_NFT_OP_CHAIN_UNREGISTER,	"nft_unregister_chain"	   },
+	{ AUDIT_NFT_OP_RULE_REGISTER,		"nft_register_rule"	   },
+	{ AUDIT_NFT_OP_RULE_UNREGISTER,		"nft_unregister_rule"	   },
+	{ AUDIT_NFT_OP_SET_REGISTER,		"nft_register_set"	   },
+	{ AUDIT_NFT_OP_SET_UNREGISTER,		"nft_unregister_set"	   },
+	{ AUDIT_NFT_OP_SETELEM_REGISTER,	"nft_register_setelem"	   },
+	{ AUDIT_NFT_OP_SETELEM_UNREGISTER,	"nft_unregister_setelem"   },
+	{ AUDIT_NFT_OP_GEN_REGISTER,		"nft_register_gen"	   },
+	{ AUDIT_NFT_OP_OBJ_REGISTER,		"nft_register_obj"	   },
+	{ AUDIT_NFT_OP_OBJ_UNREGISTER,		"nft_unregister_obj"	   },
+	{ AUDIT_NFT_OP_OBJ_RESET,		"nft_reset_obj"		   },
+	{ AUDIT_NFT_OP_FLOWTABLE_REGISTER,	"nft_register_flowtable"   },
+	{ AUDIT_NFT_OP_FLOWTABLE_UNREGISTER,	"nft_unregister_flowtable" },
+	{ AUDIT_NFT_OP_INVALID,			"nft_invalid"		   },
 };
 
 static int audit_match_perm(struct audit_context *ctx, int mask)
@@ -1876,6 +1894,20 @@ __audit_reusename(const __user char *uptr)
 	return NULL;
 }
 
+inline void _audit_getcwd(struct audit_context *context)
+{
+	if (!context->pwd.dentry)
+		get_fs_pwd(current->fs, &context->pwd);
+}
+
+void __audit_getcwd(void)
+{
+	struct audit_context *context = audit_context();
+
+	if (context->in_syscall)
+		_audit_getcwd(context);
+}
+
 /**
  * __audit_getname - add a name to the list
  * @name: name to add
@@ -1900,8 +1932,7 @@ void __audit_getname(struct filename *name)
 	name->aname = n;
 	name->refcnt++;
 
-	if (!context->pwd.dentry)
-		get_fs_pwd(current->fs, &context->pwd);
+	_audit_getcwd(context);
 }
 
 static inline int audit_copy_fcaps(struct audit_names *name,
@@ -2557,12 +2588,12 @@ void __audit_ntp_log(const struct audit_ntp_data *ad)
 }
 
 void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries,
-		       enum audit_nfcfgop op)
+		       enum audit_nfcfgop op, gfp_t gfp)
 {
 	struct audit_buffer *ab;
 	char comm[sizeof(current->comm)];
 
-	ab = audit_log_start(audit_context(), GFP_KERNEL, AUDIT_NETFILTER_CFG);
+	ab = audit_log_start(audit_context(), gfp, AUDIT_NETFILTER_CFG);
 	if (!ab)
 		return;
 	audit_log_format(ab, "table=%s family=%u entries=%u op=%s",

net/bridge/netfilter/ebtables.c

@@ -1047,7 +1047,7 @@ static int do_replace_finish(struct net *net, struct ebt_replace *repl,
 	vfree(counterstmp);
 
 	audit_log_nfcfg(repl->name, AF_BRIDGE, repl->nentries,
-			AUDIT_XT_OP_REPLACE);
+			AUDIT_XT_OP_REPLACE, GFP_KERNEL);
 	return ret;
 
 free_unlock:
@@ -1123,7 +1123,7 @@ static void __ebt_unregister_table(struct net *net, struct ebt_table *table)
 	list_del(&table->list);
 	mutex_unlock(&ebt_mutex);
 	audit_log_nfcfg(table->name, AF_BRIDGE, table->private->nentries,
-			AUDIT_XT_OP_UNREGISTER);
+			AUDIT_XT_OP_UNREGISTER, GFP_KERNEL);
 	EBT_ENTRY_ITERATE(table->private->entries, table->private->entries_size,
 			  ebt_cleanup_entry, net, NULL);
 	if (table->private->nentries)
@@ -1218,7 +1218,7 @@ int ebt_register_table(struct net *net, const struct ebt_table *input_table,
 	}
 
 	audit_log_nfcfg(repl->name, AF_BRIDGE, repl->nentries,
-			AUDIT_XT_OP_REGISTER);
+			AUDIT_XT_OP_REGISTER, GFP_KERNEL);
 	return ret;
 free_unlock:
 	mutex_unlock(&ebt_mutex);