Commit 3dc5e059 authored Nov 06, 2019 by Andrii Nakryiko Committed by Daniel Borkmann Nov 07, 2019

libbpf: Fix memory leak/double free issue

Coverity scan against Github libbpf code found the issue of not freeing memory and
leaving already freed memory still referenced from bpf_program. Fix it by
re-assigning successfully reallocated memory sooner.

Fixes: 2993e051 ("tools/bpf: add support to read .BTF.ext sections")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191107020855.3834758-2-andriin@fb.com

parent 9656b346

tools/lib/bpf/libbpf.c

+1 −1

Original line number	Diff line number	Diff line
		@@ -3523,6 +3523,7 @@ bpf_program__reloc_text(struct bpf_program prog, struct bpf_object obj,
		pr_warn("oom in prog realloc\n");
		return -ENOMEM;
		}
		prog->insns = new_insn;

		if (obj->btf_ext) {
		err = bpf_program_reloc_btf_ext(prog, obj,
		@@ -3534,7 +3535,6 @@ bpf_program__reloc_text(struct bpf_program prog, struct bpf_object obj,

		memcpy(new_insn + prog->insns_cnt, text->insns,
		text->insns_cnt * sizeof(*insn));
		prog->insns = new_insn;
		prog->main_prog_cnt = prog->insns_cnt;
		prog->insns_cnt = new_cnt;
		pr_debug("added %zd insn from %s to prog %s\n",