Commit d95f1e8b authored Feb 06, 2020 by Toke Høiland-Jørgensen Committed by Daniel Borkmann Feb 07, 2020

bpftool: Don't crash on missing xlated program instructions

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: 5b79bcdf ("bpftool: Don't crash on missing jited insns or ksyms")
Fixes: cae73f23 ("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

parent 85b8ac01

tools/bpf/bpftool/prog.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -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;
		}