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396f544ed5
For kretprobes, there is no point in capturing input arguments from pt_regs,
as they are going to be, most probably, clobbered by the time probed kernel
function returns. So switch BPF_KRETPROBE to accept zero or one argument
(optional return result).
Fixes: ac065870d9 ("selftests/bpf: Add BPF_PROG, BPF_KPROBE, and BPF_KRETPROBE macros")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200229231112.1240137-4-andriin@fb.com
43 lines
864 B
C
43 lines
864 B
C
// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2019 Facebook */
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#include <stdbool.h>
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#include <stddef.h>
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#include <linux/bpf.h>
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#include <linux/ptrace.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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#include "bpf_trace_helpers.h"
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struct task_struct;
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SEC("kprobe/__set_task_comm")
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int BPF_KPROBE(prog1, struct task_struct *tsk, const char *buf, bool exec)
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{
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return !tsk;
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}
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SEC("kretprobe/__set_task_comm")
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int BPF_KRETPROBE(prog2, int ret)
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{
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return ret;
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}
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SEC("raw_tp/task_rename")
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int prog3(struct bpf_raw_tracepoint_args *ctx)
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{
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return !ctx->args[0];
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}
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SEC("fentry/__set_task_comm")
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int BPF_PROG(prog4, struct task_struct *tsk, const char *buf, bool exec)
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{
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return !tsk;
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}
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SEC("fexit/__set_task_comm")
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int BPF_PROG(prog5, struct task_struct *tsk, const char *buf, bool exec)
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{
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return !tsk;
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}
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char _license[] SEC("license") = "GPL";
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