On Mon, May 06, 2024 at 04:30:27PM -0700, Fangrui Song wrote:
On Tue, Apr 16, 2024 at 10:28 AM Kees Cook keescook@chromium.org wrote:
On Tue, Apr 16, 2024 at 08:28:29PM +0500, Muhammad Usama Anjum wrote:
The -static overrides the -pie and binaries aren't position independent anymore. Use -static-pie instead which would produce a static and position independent binary. This has been caught by clang's warnings:
clang: warning: argument unused during compilation: '-pie' [-Wunused-command-line-argument]
Tested with both gcc and clang after this change.
Fixes: 4d1cd3b2c5c1 ("tools/testing/selftests/exec: fix link error") Signed-off-by: Muhammad Usama Anjum usama.anjum@collabora.com
Thanks for this!
Reviewed-by: Kees Cook keescook@chromium.org
-- Kees Cook
GCC versions before 8.1 do not support -static-pie, while https://www.kernel.org/doc/html/next/process/changes.html says the minimal version is GCC 5.1. Is this a problem?
If not, and CFLAGS is guaranteed to include -fpie/-fpic/-fPIE/-fPIC (PIC), using -static-pie looks good to me.
Should we use this alternative, which may be more portable? https://lore.kernel.org/all/20240504022301.35250-1-jhubbard@nvidia.com/
-Kees