diff options
| author | Eduard Zingerman <eddyz87@gmail.com> | 2025-07-18 15:20:59 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2025-08-20 18:41:06 +0200 |
| commit | a114913c34d9059b63f4632a3b1efd158871e487 (patch) | |
| tree | e02fe1d25b47a6f978c5ea12a61f0ed1e58636ad | |
| parent | a8a2b92690e61ea9ec460b08e306ec34aa2d3688 (diff) | |
libbpf: Verify that arena map exists when adding arena relocations
[ Upstream commit 42be23e8f2dcb100cb9944b2b54b6bf41aff943d ]
Fuzzer reported a memory access error in bpf_program__record_reloc()
that happens when:
- ".addr_space.1" section exists
- there is a relocation referencing this section
- there are no arena maps defined in BTF.
Sanity checks for maps existence are already present in
bpf_program__record_reloc(), hence this commit adds another one.
[1] https://github.com/libbpf/libbpf/actions/runs/16375110681/job/46272998064
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20250718222059.281526-1-eddyz87@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
| -rw-r--r-- | tools/lib/bpf/libbpf.c | 5 |
1 files changed, 5 insertions, 0 deletions
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c index d41ee26b9443..6401dd3bd35f 100644 --- a/tools/lib/bpf/libbpf.c +++ b/tools/lib/bpf/libbpf.c @@ -4582,6 +4582,11 @@ static int bpf_program__record_reloc(struct bpf_program *prog, /* arena data relocation */ if (shdr_idx == obj->efile.arena_data_shndx) { + if (obj->arena_map_idx < 0) { + pr_warn("prog '%s': bad arena data relocation at insn %u, no arena maps defined\n", + prog->name, insn_idx); + return -LIBBPF_ERRNO__RELOC; + } reloc_desc->type = RELO_DATA; reloc_desc->insn_idx = insn_idx; reloc_desc->map_idx = obj->arena_map_idx; |