fs: make binfmt support for #! scripts modular and removable
Add a new configuration option CONFIG_BINFMT_SCRIPT to configure support
for interpreted scripts starting with "#!"; allow compiling out that
support, or building it as a module. Embedded systems running exclusively
compiled binaries could leave this support out, and systems that don't
need scripts before mounting the root filesystem can build this as a
module.
Signed-off-by: Josh Triplett <josh@joshtriplett.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/Kconfig.binfmt b/fs/Kconfig.binfmt
index 0efd152..370b24c 100644
--- a/fs/Kconfig.binfmt
+++ b/fs/Kconfig.binfmt
@@ -65,6 +65,20 @@
This config option changes the default setting of coredump_filter
seen at boot time. If unsure, say Y.
+config BINFMT_SCRIPT
+ tristate "Kernel support for scripts starting with #!"
+ default y
+ help
+ Say Y here if you want to execute interpreted scripts starting with
+ #! followed by the path to an interpreter.
+
+ You can build this support as a module; however, until that module
+ gets loaded, you cannot run scripts. Thus, if you want to load this
+ module from an initramfs, the portion of the initramfs before loading
+ this module must consist of compiled binaries only.
+
+ Most systems will not boot if you say M or N here. If unsure, say Y.
+
config BINFMT_FLAT
bool "Kernel support for flat binaries"
depends on !MMU && (!FRV || BROKEN)
diff --git a/fs/Makefile b/fs/Makefile
index 3b2c767..5e67e57 100644
--- a/fs/Makefile
+++ b/fs/Makefile
@@ -34,10 +34,7 @@
obj-$(CONFIG_BINFMT_AOUT) += binfmt_aout.o
obj-$(CONFIG_BINFMT_EM86) += binfmt_em86.o
obj-$(CONFIG_BINFMT_MISC) += binfmt_misc.o
-
-# binfmt_script is always there
-obj-y += binfmt_script.o
-
+obj-$(CONFIG_BINFMT_SCRIPT) += binfmt_script.o
obj-$(CONFIG_BINFMT_ELF) += binfmt_elf.o
obj-$(CONFIG_COMPAT_BINFMT_ELF) += compat_binfmt_elf.o
obj-$(CONFIG_BINFMT_ELF_FDPIC) += binfmt_elf_fdpic.o