2024-04-16 15:28:19

by Muhammad Usama Anjum

Subject: [PATCH v2] selftests: exec: make binaries position independent

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 <[email protected]>
---
Changes since v1:
- Remove unneeded comment
---
tools/testing/selftests/exec/Makefile | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/exec/Makefile b/tools/testing/selftests/exec/Makefile
index fb4472ddffd81..3c79ec9bf780f 100644
--- a/tools/testing/selftests/exec/Makefile
+++ b/tools/testing/selftests/exec/Makefile
@@ -29,8 +29,8 @@ $(OUTPUT)/execveat.denatured: $(OUTPUT)/execveat
cp $< $@
chmod -x $@
$(OUTPUT)/load_address_4096: load_address.c
- $(CC) $(CFLAGS) $(LDFLAGS) -Wl,-z,max-page-size=0x1000 -pie -static $< -o $@
+ $(CC) $(CFLAGS) $(LDFLAGS) -Wl,-z,max-page-size=0x1000 -static-pie $< -o $@
$(OUTPUT)/load_address_2097152: load_address.c
- $(CC) $(CFLAGS) $(LDFLAGS) -Wl,-z,max-page-size=0x200000 -pie -static $< -o $@
+ $(CC) $(CFLAGS) $(LDFLAGS) -Wl,-z,max-page-size=0x200000 -static-pie $< -o $@
$(OUTPUT)/load_address_16777216: load_address.c
- $(CC) $(CFLAGS) $(LDFLAGS) -Wl,-z,max-page-size=0x1000000 -pie -static $< -o $@
+ $(CC) $(CFLAGS) $(LDFLAGS) -Wl,-z,max-page-size=0x1000000 -static-pie $< -o $@
--
2.39.2

2024-04-16 17:28:12

by Kees Cook

Subject: Re: [PATCH v2] selftests: exec: make binaries position independent

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 <[email protected]>

Thanks for this!

Reviewed-by: Kees Cook <[email protected]>

--
Kees Cook