module: ensure __cfi_check alignment
authorSami Tolvanen <samitolvanen@google.com>
Thu, 8 Apr 2021 18:28:29 +0000 (11:28 -0700)
committerKees Cook <keescook@chromium.org>
Thu, 8 Apr 2021 23:04:21 +0000 (16:04 -0700)
commit28aad1c29053195b1a9f56742e64b679d61e786b
treec7dd2f2c34527aa58d4cac71d337fed7af8f0fce
parent5caf968262df0ec7a3377fb67d4a6bfa979cb028
module: ensure __cfi_check alignment

CONFIG_CFI_CLANG_SHADOW assumes the __cfi_check() function is page
aligned and at the beginning of the .text section. While Clang would
normally align the function correctly, it fails to do so for modules
with no executable code.

This change ensures the correct __cfi_check() location and
alignment. It also discards the .eh_frame section, which Clang can
generate with certain sanitizers, such as CFI.

Link: https://bugs.llvm.org/show_bug.cgi?id=46293
Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20210408182843.1754385-5-samitolvanen@google.com
scripts/module.lds.S