When public_key_verify_signature() is called from asymmetric_key_verify_signature(), the pkey_algo field of struct public_key_signature will be NULL, which causes a NULL pointer dereference in the strcmp() check. Fix this by adding a NULL check. One visible manifestation of this is that userspace programs (such as the 'iwd' WiFi daemon) will be killed when trying to verify a TLS key using the keyctl(2) interface. Cc: stable@xxxxxxxxxxxxxxx Fixes: 215525639631 ("X.509: support OSCCA SM2-with-SM3 certificate verification") Signed-off-by: Toke Høiland-Jørgensen <toke@xxxxxxxxxx> --- crypto/asymmetric_keys/public_key.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c index 8892908ad58c..35b09e95a870 100644 --- a/crypto/asymmetric_keys/public_key.c +++ b/crypto/asymmetric_keys/public_key.c @@ -356,7 +356,7 @@ int public_key_verify_signature(const struct public_key *pkey, if (ret) goto error_free_key; - if (strcmp(sig->pkey_algo, "sm2") == 0 && sig->data_size) { + if (sig->pkey_algo && strcmp(sig->pkey_algo, "sm2") == 0 && sig->data_size) { ret = cert_sig_digest_update(sig, tfm); if (ret) goto error_free_key; -- 2.30.0