[PATCH] lsm: Early init for security modules (1/4)

As discussed before, this allows for early initialization of security
modules when compiled statically into the kernel.  The standard
do_initcalls is too late for complete coverage of all filesystems and
threads, for example.

arch/alpha/vmlinux.lds.S

@@ -74,6 +74,9 @@ SECTIONS
 	__con_initcall_end = .;
   }
 
+  . = ALIGN(8);
+  SECURITY_INIT
+
   . = ALIGN(64);
   __per_cpu_start = .;
   .data.percpu : { *(.data.percpu) }

arch/arm/vmlinux-armo.lds.in

@@ -43,6 +43,7 @@ SECTIONS
 		__con_initcall_start = .;
 			*(.con_initcall.init)
 		__con_initcall_end = .;
+		SECURITY_INIT
 		. = ALIGN(32768);
 		__init_end = .;
 	}

arch/arm/vmlinux-armv.lds.in

@@ -53,6 +53,7 @@ SECTIONS
 		__con_initcall_start = .;
 			*(.con_initcall.init)
 		__con_initcall_end = .;
+		SECURITY_INIT
 		. = ALIGN(32);
 		__initramfs_start = .;
 			usr/built-in.o(.init.ramfs)

arch/cris/vmlinux.lds.S

@@ -74,7 +74,12 @@ SECTIONS
 		__con_initcall_start = .;
 		*(.con_initcall.init)
 		__con_initcall_end = .;
-	
+	}
+	.security_initcall.init : {
+		__security_initcall_start = .;
+		*(.security_initcall.init)
+		__security_initcall_end = .;
+
 		/* We fill to the next page, so we can discard all init
 		   pages without needing to consider what payload might be
 		   appended to the kernel image.  */

arch/h8300/platform/h8300h/generic/rom.ld

@@ -83,6 +83,7 @@ SECTIONS
 	___con_initcall_start = .;
 		*(.con_initcall.init)
 	___con_initcall_end = .;
+	SECURITY_INIT
 		. = ALIGN(4);
 	___initramfs_start = .;
   		*(.init.ramfs)

arch/i386/vmlinux.lds.S

@@ -81,6 +81,7 @@ SECTIONS
   __con_initcall_start = .;
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
+  SECURITY_INIT
   . = ALIGN(4);
   __alt_instructions = .;
   .altinstructions : { *(.altinstructions) } 

arch/ia64/vmlinux.lds.S

@@ -141,6 +141,10 @@ SECTIONS
   .con_initcall.init : AT(ADDR(.con_initcall.init) - PAGE_OFFSET)
 	{ *(.con_initcall.init) }
   __con_initcall_end = .;
+  __security_initcall_start = .;
+  .security_initcall.init : AT(ADDR(.security_initcall.init) - PAGE_OFFSET)
+	{ *(.security_initcall.init) }
+  __security_initcall_end = .;
   . = ALIGN(PAGE_SIZE);
   __init_end = .;
 

arch/m68k/vmlinux-std.lds

@@ -67,6 +67,7 @@ SECTIONS
   __con_initcall_start = .;
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
+  SECURITY_INIT
   . = ALIGN(8192);
   __initramfs_start = .;
   .init.ramfs : { *(.init.ramfs) }

arch/m68k/vmlinux-sun3.lds

@@ -61,6 +61,7 @@ __init_begin = .;
 	__con_initcall_start = .;
 	.con_initcall.init : { *(.con_initcall.init) }
 	__con_initcall_end = .;
+	SECURITY_INIT
 	. = ALIGN(8192);
 	__initramfs_start = .;
 	.init.ramfs : { *(.init.ramfs) }

arch/m68knommu/vmlinux.lds.S

@@ -277,9 +277,7 @@ SECTIONS {
 		__con_initcall_start = .;
 		*(.con_initcall.init)
 		__con_initcall_end = .;
-		__security_initcall_start = .;
-		*(.security_initcall.init)
-		__security_initcall_end = .;
+		SECURITY_INIT
 		. = ALIGN(4);
 		__initramfs_start = .;
 		*(.init.ramfs)

arch/mips/vmlinux.lds.S

@@ -54,6 +54,7 @@ SECTIONS
   __con_initcall_start = .;
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
+  SECURITY_INIT
   . = ALIGN(4096);	/* Align double page for init_task_union */
   __init_end = .;
 

arch/mips64/vmlinux.lds.S

@@ -53,6 +53,7 @@ SECTIONS
   __con_initcall_start = .;
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
+  SECURITY_INIT
   . = ALIGN(4096);	/* Align double page for init_task_union */
   __init_end = .;
 

arch/parisc/vmlinux.lds.S

@@ -80,6 +80,7 @@ SECTIONS
   __con_initcall_start = .;
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
+  SECURITY_INIT
   . = ALIGN(4096);
   __initramfs_start = .;
   .init.ramfs : { *(.init.ramfs) }

arch/ppc/vmlinux.lds.S

@@ -119,6 +119,8 @@ SECTIONS
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
 
+  SECURITY_INIT
+
   __start___ftr_fixup = .;
   __ftr_fixup : { *(__ftr_fixup) }
   __stop___ftr_fixup = .;

arch/ppc64/vmlinux.lds.S

@@ -104,6 +104,7 @@ SECTIONS
   __con_initcall_start = .;
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
+  SECURITY_INIT
   . = ALIGN(4096);
   __initramfs_start = .;
   .init.ramfs : { *(.init.ramfs) }

arch/s390/vmlinux.lds.S

@@ -94,6 +94,7 @@ SECTIONS
   __con_initcall_start = .;
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
+  SECURITY_INIT
   . = ALIGN(256);
   __initramfs_start = .;
   .init.ramfs : { *(.init.initramfs) }

arch/sh/vmlinux.lds.S

@@ -71,6 +71,7 @@ SECTIONS
   __con_initcall_start = .;
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
+  SECURITY_INIT
   __machvec_start = .;
   .machvec.init : { *(.machvec.init) }
   __machvec_end = .;

arch/sparc/vmlinux.lds.S

@@ -62,6 +62,7 @@ SECTIONS
   __con_initcall_start = .;
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
+  SECURITY_INIT
   . = ALIGN(4096);
   __initramfs_start = .;
   .init.ramfs : { *(.init.ramfs) }

arch/sparc64/vmlinux.lds.S

@@ -68,6 +68,7 @@ SECTIONS
   __con_initcall_start = .;
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
+  SECURITY_INIT
   . = ALIGN(8192); 
   __initramfs_start = .;
   .init.ramfs : { *(.init.ramfs) }

arch/x86_64/vmlinux.lds.S

@@ -105,6 +105,7 @@ SECTIONS
   __con_initcall_start = .;
   .con_initcall.init : { *(.con_initcall.init) }
   __con_initcall_end = .;
+  SECURITY_INIT
   . = ALIGN(4096);
   __initramfs_start = .;
   .init.ramfs : { *(.init.ramfs) }

include/asm-generic/vmlinux.lds.h

@@ -45,3 +45,9 @@
 		*(__ksymtab_strings)					\
 	}
 
+#define SECURITY_INIT							\
+	.security_initcall.init : {					\
+		__security_initcall_start = .;				\
+		*(.security_initcall.init) 				\
+		__security_initcall_end = .;				\
+	}

include/linux/init.h

@@ -64,6 +64,7 @@ typedef int (*initcall_t)(void);
 typedef void (*exitcall_t)(void);
 
 extern initcall_t __con_initcall_start, __con_initcall_end;
+extern initcall_t __security_initcall_start, __security_initcall_end;
 #endif
   
 #ifndef MODULE
@@ -96,6 +97,9 @@ extern initcall_t __con_initcall_start, __con_initcall_end;
 #define console_initcall(fn) \
 	static initcall_t __initcall_##fn __attribute__ ((unused,__section__ (".con_initcall.init")))=fn
 
+#define security_initcall(fn) \
+	static initcall_t __initcall_##fn __attribute__ ((unused,__section__ (".security_initcall.init"))) = fn
+
 struct obs_kernel_param {
 	const char *str;
 	int (*setup_func)(char *);
@@ -143,6 +147,8 @@ struct obs_kernel_param {
 #define device_initcall(fn)		module_init(fn)
 #define late_initcall(fn)		module_init(fn)
 
+#define security_initcall(fn)		module_init(fn)
+
 /* These macros create a dummy inline: gcc 2.9x does not count alias
  as usage, hence the `unused function' warning when __init functions
  are declared static. We use the dummy __*_module_inline functions

init/main.c

@@ -439,8 +439,8 @@ asmlinkage void __init start_kernel(void)
 	pte_chain_init();
 	fork_init(num_physpages);
 	proc_caches_init();
-	security_scaffolding_startup();
 	buffer_init();
+	security_scaffolding_startup();
 	vfs_caches_init(num_physpages);
 	radix_tree_init();
 	signals_init();

security/capability.c

@@ -348,7 +348,7 @@ static void __exit capability_exit (void)
 	}
 }
 
-module_init (capability_init);
+security_initcall (capability_init);
 module_exit (capability_exit);
 
 MODULE_DESCRIPTION("Standard Linux Capabilities Security Module");

security/root_plug.c

@@ -135,7 +135,7 @@ static void __exit rootplug_exit (void)
 	printk (KERN_INFO "Root Plug module removed\n");
 }
 
-module_init (rootplug_init);
+security_initcall (rootplug_init);
 module_exit (rootplug_exit);
 
 MODULE_DESCRIPTION("Root Plug sample LSM module, written for Linux Journal article");

security/security.c

@@ -38,12 +38,22 @@ static inline int verify (struct security_operations *ops)
 	return 0;
 }
 
+static void __init do_security_initcalls(void)
+{
+	initcall_t *call;
+	call = &__security_initcall_start;
+	while (call < &__security_initcall_end) {
+		(*call)();
+		call++;
+	}
+}
+
 /**
  * security_scaffolding_startup - initialzes the security scaffolding framework
  *
  * This should be called early in the kernel initialization sequence.
  */
-int security_scaffolding_startup (void)
+int __init security_scaffolding_startup (void)
 {
 	printk (KERN_INFO "Security Scaffold v" SECURITY_SCAFFOLD_VERSION
 		" initialized\n");
@@ -55,6 +65,7 @@ int security_scaffolding_startup (void)
 	}
 
 	security_ops = &dummy_security_ops;
+	do_security_initcalls();
 
 	return 0;
 }