| From d95f1e8b462c4372ac409886070bb8719d8a4d3a Mon Sep 17 00:00:00 2001 |
| From: =?UTF-8?q?Toke=20H=C3=B8iland-J=C3=B8rgensen?= <toke@redhat.com> |
| Date: Thu, 6 Feb 2020 11:29:06 +0100 |
| Subject: bpftool: Don't crash on missing xlated program instructions |
| MIME-Version: 1.0 |
| Content-Type: text/plain; charset=UTF-8 |
| Content-Transfer-Encoding: 8bit |
| |
| From: Toke Høiland-Jørgensen <toke@redhat.com> |
| |
| commit d95f1e8b462c4372ac409886070bb8719d8a4d3a upstream. |
| |
| 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 <toke@redhat.com> |
| Signed-off-by: Daniel Borkmann <daniel@iogearbox.net> |
| Reviewed-by: Quentin Monnet <quentin@isovalent.com> |
| Link: https://lore.kernel.org/bpf/20200206102906.112551-1-toke@redhat.com |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| tools/bpf/bpftool/prog.c | 2 +- |
| 1 file changed, 1 insertion(+), 1 deletion(-) |
| |
| --- a/tools/bpf/bpftool/prog.c |
| +++ b/tools/bpf/bpftool/prog.c |
| @@ -500,7 +500,7 @@ static int do_dump(int argc, char **argv |
| 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?"); |
| goto err_free; |
| } |
