selftests/bpf: Add tests for fault prone loads out of RCU pointers

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Cover the two loads which used to lose the BPF_PROBE_MEM rewrite, both reached
from an RCU read-side critical section. The purpose of this patch is to assert
load success in order to make sure to not trigger verifier_bug_if() on
bpf_may_fault_on_deref() due to forgotten rewrite of a probed pointer.

  # LDLIBS=-static PKG_CONFIG='pkg-config --static' ./vmtest.sh -- ./test_progs -t rcu_read_lock
  [...]
  #332/1   rcu_read_lock/success:OK
  #332/2   rcu_read_lock/rcuptr_acquire:OK
  #332/3   rcu_read_lock/negative_tests_inproper_region:OK
  #332/4   rcu_read_lock/negative_tests_rcuptr_misuse:OK
  #332     rcu_read_lock:OK
  Summary: 1/4 PASSED, 0 SKIPPED, 0/0 FAILED

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/bpf/20260817141015.878071-2-daniel@iogearbox.net
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

...

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Daniel Borkmann 2026-08-17 16:10:14 +02:00 • committed by Kumar Kartikeya Dwivedi

parent 78d8e5b375

commit 2b918fe2f1

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tools/testing/selftests/bpf/prog_tests/rcu_read_lock.c

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76

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

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