From 81366e333c7e034cc2e86021f1e5accdfc37ab7f Mon Sep 17 00:00:00 2001 From: Quentin Monnet Date: Wed, 5 Apr 2023 14:21:15 +0100 Subject: [PATCH] bpftool: Fix bug for long instructions in program CFG dumps [ Upstream commit 67cf52cdb6c8fa6365d29106555dacf95c9fd374 ] When dumping the control flow graphs for programs using the 16-byte long load instruction, we need to skip the second part of this instruction when looking for the next instruction to process. Otherwise, we end up printing "BUG_ld_00" from the kernel disassembler in the CFG. Fixes: efcef17a6d65 ("tools: bpftool: generate .dot graph from CFG information") Signed-off-by: Quentin Monnet Link: https://lore.kernel.org/r/20230405132120.59886-3-quentin@isovalent.com Signed-off-by: Alexei Starovoitov Signed-off-by: Sasha Levin --- tools/bpf/bpftool/xlated_dumper.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/tools/bpf/bpftool/xlated_dumper.c b/tools/bpf/bpftool/xlated_dumper.c index 2d9cd6a..d9386a1 100644 --- a/tools/bpf/bpftool/xlated_dumper.c +++ b/tools/bpf/bpftool/xlated_dumper.c @@ -370,8 +370,15 @@ void dump_xlated_for_graph(struct dump_data *dd, void *buf_start, void *buf_end, struct bpf_insn *insn_start = buf_start; struct bpf_insn *insn_end = buf_end; struct bpf_insn *cur = insn_start; + bool double_insn = false; for (; cur <= insn_end; cur++) { + if (double_insn) { + double_insn = false; + continue; + } + double_insn = cur->code == (BPF_LD | BPF_IMM | BPF_DW); + printf("% 4d: ", (int)(cur - insn_start + start_idx)); print_bpf_insn(&cbs, cur, true); if (cur != insn_end) -- 2.7.4