AUDIT: Report lookup flags with path/inode records.

When LOOKUP_PARENT is used, the inode which results is not the inode
found at the pathname. Report the flags so that this doesn't generate
misleading audit records.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>

fs/namei.c

@@ -1043,7 +1043,7 @@ int fastcall path_lookup(const char *name, unsigned int flags, struct nameidata
 out:
 	if (unlikely(current->audit_context
 		     && nd && nd->dentry && nd->dentry->d_inode))
-		audit_inode(name, nd->dentry->d_inode);
+		audit_inode(name, nd->dentry->d_inode, flags);
 	return retval;
 }
 

include/linux/audit.h

@@ -220,7 +220,7 @@ extern void audit_syscall_entry(struct task_struct *task, int arch,
 extern void audit_syscall_exit(struct task_struct *task, int failed, long return_code);
 extern void audit_getname(const char *name);
 extern void audit_putname(const char *name);
-extern void audit_inode(const char *name, const struct inode *inode);
+extern void audit_inode(const char *name, const struct inode *inode, unsigned flags);
 
 				/* Private API (for audit.c only) */
 extern int  audit_receive_filter(int type, int pid, int uid, int seq,
@@ -243,7 +243,7 @@ extern int audit_filter_user(struct task_struct *tsk, int type);
 #define audit_syscall_exit(t,f,r) do { ; } while (0)
 #define audit_getname(n) do { ; } while (0)
 #define audit_putname(n) do { ; } while (0)
-#define audit_inode(n,i) do { ; } while (0)
+#define audit_inode(n,i,f) do { ; } while (0)
 #define audit_receive_filter(t,p,u,s,d,l) ({ -EOPNOTSUPP; })
 #define auditsc_get_stamp(c,t,s) do { BUG(); } while (0)
 #define audit_get_loginuid(c) ({ -1; })

kernel/auditsc.c

@@ -95,6 +95,7 @@ struct audit_names {
 	uid_t		uid;
 	gid_t		gid;
 	dev_t		rdev;
+	unsigned	flags;
 };
 
 struct audit_aux_data {
@@ -792,6 +793,8 @@ static void audit_log_exit(struct audit_context *context)
 			audit_log_format(ab, " name=");
 			audit_log_untrustedstring(ab, context->names[i].name);
 		}
+		audit_log_format(ab, " flags=%x\n", context->names[i].flags);
+
 		if (context->names[i].ino != (unsigned long)-1)
 			audit_log_format(ab, " inode=%lu dev=%02x:%02x mode=%#o"
 					     " ouid=%u ogid=%u rdev=%02x:%02x",
@@ -1018,7 +1021,7 @@ void audit_putname(const char *name)
 
 /* Store the inode and device from a lookup.  Called from
  * fs/namei.c:path_lookup(). */
-void audit_inode(const char *name, const struct inode *inode)
+void audit_inode(const char *name, const struct inode *inode, unsigned flags)
 {
 	int idx;
 	struct audit_context *context = current->audit_context;
@@ -1044,12 +1047,13 @@ void audit_inode(const char *name, const struct inode *inode)
 		++context->ino_count;
 #endif
 	}
-	context->names[idx].ino  = inode->i_ino;
-	context->names[idx].dev	 = inode->i_sb->s_dev;
-	context->names[idx].mode = inode->i_mode;
-	context->names[idx].uid  = inode->i_uid;
-	context->names[idx].gid  = inode->i_gid;
-	context->names[idx].rdev = inode->i_rdev;
+	context->names[idx].flags = flags;
+	context->names[idx].ino   = inode->i_ino;
+	context->names[idx].dev	  = inode->i_sb->s_dev;
+	context->names[idx].mode  = inode->i_mode;
+	context->names[idx].uid   = inode->i_uid;
+	context->names[idx].gid   = inode->i_gid;
+	context->names[idx].rdev  = inode->i_rdev;
 }
 
 void auditsc_get_stamp(struct audit_context *ctx,