62 lines
1.2 KiB
C
62 lines
1.2 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2022 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/bpf_helpers.h>
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static struct prog_test_ref_kfunc __kptr_ref *v;
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long total_sum = -1;
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extern struct prog_test_ref_kfunc *bpf_kfunc_call_test_acquire(unsigned long *sp) __ksym;
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extern void bpf_kfunc_call_test_release(struct prog_test_ref_kfunc *p) __ksym;
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SEC("tc")
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int test_jit_probe_mem(struct __sk_buff *ctx)
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{
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struct prog_test_ref_kfunc *p;
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unsigned long zero = 0, sum;
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p = bpf_kfunc_call_test_acquire(&zero);
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if (!p)
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return 1;
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p = bpf_kptr_xchg(&v, p);
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if (p)
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goto release_out;
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/* Direct map value access of kptr, should be PTR_UNTRUSTED */
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p = v;
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if (!p)
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return 1;
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asm volatile (
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"r9 = %[p];"
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"%[sum] = 0;"
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/* r8 = p->a */
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"r8 = *(u32 *)(r9 + 0);"
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"%[sum] += r8;"
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/* r8 = p->b */
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"r8 = *(u32 *)(r9 + 4);"
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"%[sum] += r8;"
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"r9 += 8;"
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/* r9 = p->a */
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"r9 = *(u32 *)(r9 - 8);"
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"%[sum] += r9;"
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: [sum] "=r"(sum)
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: [p] "r"(p)
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: "r8", "r9"
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);
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total_sum = sum;
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return 0;
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release_out:
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bpf_kfunc_call_test_release(p);
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return 1;
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}
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char _license[] SEC("license") = "GPL";
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