From d95f1e8b462c4372ac409886070bb8719d8a4d3a Mon Sep 17 00:00:00 2001 From: =?utf8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= Date: Thu, 6 Feb 2020 11:29:06 +0100 Subject: [PATCH] bpftool: Don't crash on missing xlated program instructions MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit Turns out the xlated program instructions can also be missing if kptr_restrict sysctl is set. This means that the previous fix to check the jited_prog_insns pointer was insufficient; add another check of the xlated_prog_insns pointer as well. Fixes: 5b79bcdf0362 ("bpftool: Don't crash on missing jited insns or ksyms") Fixes: cae73f233923 ("bpftool: use bpf_program__get_prog_info_linear() in prog.c:do_dump()") Signed-off-by: Toke Høiland-Jørgensen Signed-off-by: Daniel Borkmann Reviewed-by: Quentin Monnet Link: https://lore.kernel.org/bpf/20200206102906.112551-1-toke@redhat.com --- tools/bpf/bpftool/prog.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/tools/bpf/bpftool/prog.c b/tools/bpf/bpftool/prog.c index a3521deca869..b352ab041160 100644 --- a/tools/bpf/bpftool/prog.c +++ b/tools/bpf/bpftool/prog.c @@ -536,7 +536,7 @@ prog_dump(struct bpf_prog_info *info, enum dump_mode mode, buf = (unsigned char *)(info->jited_prog_insns); member_len = info->jited_prog_len; } else { /* DUMP_XLATED */ - if (info->xlated_prog_len == 0) { + if (info->xlated_prog_len == 0 || !info->xlated_prog_insns) { p_err("error retrieving insn dump: kernel.kptr_restrict set?"); return -1; } -- 2.20.1