selftests/bpf: Cover frame changes in bounded loops

Browse source

Add a finite loop whose progress is represented only by changing the
frame number of a stack pointer. The loop first reads zero from the
caller's stack, switches to the same offset in the callee's stack, and
exits after reading one on its next iteration.

Force frequent checkpoints so the test exercises infinite-loop detection,
and check that the program returns one when run.

Without the frameno comparison in regs_exact(), the program is rejected
with an "infinite loop detected" diagnostic instead of loading
successfully.

Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://patch.msgid.link/20260919014213.1840880-3-memxor@gmail.com

...

This commit is contained in:

Kumar Kartikeya Dwivedi 2026-09-19 03:42:11 +02:00 • committed by Alexei Starovoitov

parent 8901cee931

commit 0705878489

No known key found for this signature in database

1 changed files with 36 additions and 0 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

36

tools/testing/selftests/bpf/progs/verifier_loops1.c

View file