00f239eccf
Test if the verifier verifies nullable pointer arguments correctly for BPF struct_ops programs. "test_maybe_null" in struct bpf_testmod_ops is the operator defined for the test cases here. A BPF program should check a pointer for NULL beforehand to access the value pointed by the nullable pointer arguments, or the verifier should reject the programs. The test here includes two parts; the programs checking pointers properly and the programs not checking pointers beforehand. The test checks if the verifier accepts the programs checking properly and rejects the programs not checking at all. Signed-off-by: Kui-Feng Lee <thinker.li@gmail.com> Link: https://lore.kernel.org/r/20240209023750.1153905-5-thinker.li@gmail.com Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
29 lines
698 B
C
29 lines
698 B
C
// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2024 Meta Platforms, Inc. and affiliates. */
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#include <vmlinux.h>
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#include <bpf/bpf_tracing.h>
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#include "../bpf_testmod/bpf_testmod.h"
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char _license[] SEC("license") = "GPL";
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pid_t tgid = 0;
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/* This is a test BPF program that uses struct_ops to access an argument
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* that may be NULL. This is a test for the verifier to ensure that it can
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* rip PTR_MAYBE_NULL correctly.
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*/
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SEC("struct_ops/test_maybe_null")
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int BPF_PROG(test_maybe_null, int dummy,
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struct task_struct *task)
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{
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if (task)
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tgid = task->tgid;
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return 0;
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}
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SEC(".struct_ops.link")
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struct bpf_testmod_ops testmod_1 = {
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.test_maybe_null = (void *)test_maybe_null,
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};
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