ffed24eff9
Adding test that tries to trigger the BUG_IN during early map update in prog_array_map_poke_run function. The idea is to share prog array map between thread that constantly updates it and another one loading a program that uses that prog array. Eventually we will hit a place where the program is ok to be updated (poke->tailcall_target_stable check) but the address is still not registered in kallsyms, so the bpf_arch_text_poke returns -EINVAL and cause imbalance for the next tail call update check, which will fail with -EBUSY in bpf_arch_text_poke as described in previous fix. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> Acked-by: Ilya Leoshkevich <iii@linux.ibm.com> Link: https://lore.kernel.org/bpf/20231206083041.1306660-3-jolsa@kernel.org
32 lines
594 B
C
32 lines
594 B
C
// SPDX-License-Identifier: GPL-2.0
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#include <linux/bpf.h>
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#include <bpf/bpf_helpers.h>
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#include <bpf/bpf_tracing.h>
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char _license[] SEC("license") = "GPL";
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struct {
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__uint(type, BPF_MAP_TYPE_PROG_ARRAY);
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__uint(max_entries, 1);
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__uint(key_size, sizeof(__u32));
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__uint(value_size, sizeof(__u32));
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} jmp_table SEC(".maps");
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SEC("?fentry/bpf_fentry_test1")
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int BPF_PROG(test, int a)
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{
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bpf_tail_call_static(ctx, &jmp_table, 0);
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return 0;
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}
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SEC("fentry/bpf_fentry_test1")
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int BPF_PROG(call1, int a)
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{
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return 0;
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}
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SEC("fentry/bpf_fentry_test1")
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int BPF_PROG(call2, int a)
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{
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return 0;
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}
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