Commit 1cb61759 authored by Marco Elver's avatar Marco Elver Committed by Kees Cook

init: verify that function is initcall_t at compile-time

In the spirit of making it hard to misuse an interface, add a
compile-time assertion in the CONFIG_HAVE_ARCH_PREL32_RELOCATIONS case
to verify the initcall function matches initcall_t, because the inline
asm bypasses any type-checking the compiler would otherwise do. This
will help developers catch incorrect API use in all configurations.

A recent example of this is:
https://lkml.kernel.org/r/20210514140015.2944744-1-arnd@kernel.orgSigned-off-by: default avatarMarco Elver <elver@google.com>
Reviewed-by: default avatarMiguel Ojeda <ojeda@kernel.org>
Reviewed-by: default avatarNathan Chancellor <nathan@kernel.org>
Tested-by: default avatarNathan Chancellor <nathan@kernel.org>
Reviewed-by: default avatarSami Tolvanen <samitolvanen@google.com>
Tested-by: default avatarPaul E. McKenney <paulmck@kernel.org>
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210521072610.2880286-1-elver@google.com
parent d07f6ca9
......@@ -242,7 +242,8 @@ extern bool initcall_debug;
asm(".section \"" __sec "\", \"a\" \n" \
__stringify(__name) ": \n" \
".long " __stringify(__stub) " - . \n" \
".previous \n");
".previous \n"); \
static_assert(__same_type(initcall_t, &fn));
#else
#define ____define_initcall(fn, __unused, __name, __sec) \
static initcall_t __name __used \
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment