Commit 8ca990ce authored by Andrii Nakryiko's avatar Andrii Nakryiko Committed by Daniel Borkmann
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libbpf: fix detection of corrupted BPF instructions section 



Ensure that size of a section w/ BPF instruction is exactly a multiple
of BPF instruction size.

Signed-off-by: default avatarAndrii Nakryiko <andriin@fb.com>
Acked-by: default avatarSong Liu <songliubraving@fb.com>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
parent 501b125a

tools/lib/bpf/libbpf.c

+7 −5
Original line number Diff line number Diff line
@@ -349,8 +349,11 @@ static int 
bpf_program__init(void *data, size_t size, char *section_name, int idx,

		  struct bpf_program *prog)

{

	if (size < sizeof(struct bpf_insn)) {

		pr_warning("corrupted section '%s'\n", section_name);

	const size_t bpf_insn_sz = sizeof(struct bpf_insn);



	if (size == 0 || size % bpf_insn_sz) {

		pr_warning("corrupted section '%s', size: %zu\n",

			   section_name, size);

		return -EINVAL;

	}
@@ -376,9 +379,8 @@ bpf_program__init(void *data, size_t size, char *section_name, int idx, 
			   section_name);

		goto errout;

	}

	prog->insns_cnt = size / sizeof(struct bpf_insn);

	memcpy(prog->insns, data,

	       prog->insns_cnt * sizeof(struct bpf_insn));

	prog->insns_cnt = size / bpf_insn_sz;

	memcpy(prog->insns, data, size);

	prog->idx = idx;

	prog->instances.fds = NULL;

	prog->instances.nr = -1;