Re: [PATCH v2] selftests: fix relative rpath usage

[Shuah Khan <skhan@xxxxxxxxxxxxxxxxxxx>]

On 8/12/24 10:56, Eugene Syromiatnikov wrote:
> The relative RPATH ("./") supplied to linker options in CFLAGS is resolved
> relative to current working directory and not the executable directory,
> which will lead in incorrect resolution when the test executables are run
> from elsewhere.  Changing it to $ORIGIN makes it resolve relative
> to the directory in which the executables reside, which is supposedly
> the desired behaviour.  This patch also moves these CFLAGS to lib.mk,
> so the RPATH is provided for all selftest binaries, which is arguably
> a useful default.

Can you elaborate on the erros you would see if this isn't fixed? I understand
that check-rpaths tool - howebver I would like to know how it manifests and
how would you reproduce this problem while running selftests?


> Discovered by the check-rpaths script[1][2] that checks for insecure
> RPATH/RUNPATH[3], such as relative directories, during an attempt
> to package BPF selftests for later use in CI:
>
>      ERROR   0004: file '/usr/libexec/kselftests/bpf/urandom_read' contains an insecure runpath '.' in [.]
>
> [1] https://github.com/rpm-software-management/rpm/blob/master/scripts/check-rpaths
> [2] https://github.com/rpm-software-management/rpm/blob/master/scripts/check-rpaths-worker
> [3] https://cwe.mitre.org/data/definitions/426.html
>
> Signed-off-by: Eugene Syromiatnikov <esyr@xxxxxxxxxx>
> ---
> v2:
>    - Consolidated the updated -L/-Wl,-rpath setting into lib.mk
>    - Described the testing done in the commit message
> v1: https://lore.kernel.org/lkml/20240808145639.GA20510@xxxxxxxxxxxxxxxxx/
>      https://lore.kernel.org/lkml/20240808151335.GA5495@xxxxxxxxxxxxxxxxx/
>      https://lore.kernel.org/lkml/20240808151621.GA10025@xxxxxxxxxxxxxxxxx/
>      https://lore.kernel.org/lkml/20240808151621.GA10025@xxxxxxxxxxxxxxxxx/
> ---
>   tools/testing/selftests/alsa/Makefile  | 1 -
>   tools/testing/selftests/bpf/Makefile   | 5 ++---
>   tools/testing/selftests/lib.mk         | 3 +++
>   tools/testing/selftests/rseq/Makefile  | 2 +-
>   tools/testing/selftests/sched/Makefile | 3 +--
>   5 files changed, 7 insertions(+), 7 deletions(-)

thanks,
-- Shuah