Bugzilla: https://bugzilla.redhat.com/2069046
Upstream Status: git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
commit c23551c9c36ae394f9c53a5adf1944a943c65e0b
Author: Alan Maguire <alan.maguire@oracle.com>
Date: Fri Nov 5 16:50:46 2021 +0000
selftests/bpf: Add exception handling selftests for tp_bpf program
Exception handling is triggered in BPF tracing programs when a NULL pointer
is dereferenced; the exception handler zeroes the target register and
execution of the BPF program progresses.
To test exception handling then, we need to trigger a NULL pointer dereference
for a field which should never be zero; if it is, the only explanation is the
exception handler ran. task->task_works is the NULL pointer chosen (for a new
task from fork() no work is associated), and the task_works->func field should
not be zero if task_works is non-NULL. The test verifies that task_works and
task_works->func are 0.
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/1636131046-5982-3-git-send-email-alan.maguire@oracle.com
Signed-off-by: Artem Savkov <asavkov@redhat.com>