[PATCH bpf-next v6 4/8] bpftool: Check EVP_Digest when computing excl_prog_hash
Daniel Borkmann <[email protected]>
| Newsgroups | org.kernel.vger.linux-security-module,org.kernel.vger.bpf |
|---|---|
| Message-ID | <[email protected]> |
bpftool_prog_sign() ignores the return value of EVP_Digest(). If the
digest computation fails (context allocation failure, or a digest
fetch failure under OpenSSL), EVP_Digest() returns 0 and leaves the
output buffer untouched, but the function still reports success.
Fixes: 40863f4d6ef2 ("bpftool: Add support for signing BPF programs")
Signed-off-by: Daniel Borkmann <[email protected]>
---
tools/bpf/bpftool/sign.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/tools/bpf/bpftool/sign.c b/tools/bpf/bpftool/sign.c
index f9b742f4bb10..1257dba8ef2f 100644
--- a/tools/bpf/bpftool/sign.c
+++ b/tools/bpf/bpftool/sign.c
@@ -175,8 +175,11 @@ int bpftool_prog_sign(struct bpf_load_and_run_opts *opts)
goto cleanup;
}
- EVP_Digest(opts->insns, opts->insns_sz, opts->excl_prog_hash,
- &opts->excl_prog_hash_sz, EVP_sha256(), NULL);
+ if (EVP_Digest(opts->insns, opts->insns_sz, opts->excl_prog_hash,
+ &opts->excl_prog_hash_sz, EVP_sha256(), NULL) != 1) {
+ err = -EIO;
+ goto cleanup;
+ }
bd_out = BIO_new(BIO_s_mem());
if (!bd_out) {
--
2.43.0