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| author | Eduard Zingerman <eddyz87@gmail.com> | 2026-09-04 17:05:55 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2026-09-04 18:17:30 -0700 |
| commit | 100f4cc0d59be88d2b4d6eb42e51910ea2548d04 (patch) | |
| tree | 12429112aa15c4ca8a2b1b485eedfc1b860c18b3 | |
| parent | f1e418129f2ebb5376df2f1cd19720fa80f8adb4 (diff) | |
| download | linux-next-100f4cc0d59be88d2b4d6eb42e51910ea2548d04.tar.gz linux-next-100f4cc0d59be88d2b4d6eb42e51910ea2548d04.zip | |
selftests/bpf: precision of a NULL global subprogram memory argument
Check that mark_chain_precision() is called for a NULL pointer passed
as a nullable pointer argument of a global subprogram.
(Pointer arguments of the global subprograms are nullable by default).
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-4-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| -rw-r--r-- | tools/testing/selftests/bpf/progs/verifier_precision.c | 32 |
1 files changed, 32 insertions, 0 deletions
diff --git a/tools/testing/selftests/bpf/progs/verifier_precision.c b/tools/testing/selftests/bpf/progs/verifier_precision.c index 3e290b07f672..fb7dfa1246ef 100644 --- a/tools/testing/selftests/bpf/progs/verifier_precision.c +++ b/tools/testing/selftests/bpf/progs/verifier_precision.c @@ -676,4 +676,36 @@ __naked int null_mem_arg_zero_size(void) : __clobber_all); } +__weak int subprog_mem_arg(int *p) +{ + if (p) + return *p; + return 0; +} + +/* + * Verification takes two paths: with r1 being scalar zero on path (1) + * and with r1 being some other scalar on path (2). + * Check that the verifier does not use checkpoints created + * on path (1) to prune path (2). + */ +SEC("?raw_tp") +__flag(BPF_F_TEST_STATE_FREQ) +__failure __msg("R1 type=scalar expected=fp") +__naked int null_mem_arg_global_subprog(void) +{ + asm volatile ( + "call %[bpf_get_prandom_u32];" + "r1 = 42;" + "if r0 > 42 goto 1f;" + "r1 = 0;" + "1:" + "call subprog_mem_arg;" + "r0 = 0;" + "exit;" + : + : __imm(bpf_get_prandom_u32) + : __clobber_all); +} + char _license[] SEC("license") = "GPL"; |