From: Tianjia Zhang Date: Thu, 7 Jan 2021 09:28:55 +0000 (+0800) Subject: X.509: Fix crash caused by NULL pointer X-Git-Tag: archive/raspbian/5.10.9-1+rpi1^2~27 X-Git-Url: https://dgit.raspbian.org/?a=commitdiff_plain;h=3dd8b0a66c292255587a5c5e785d19c45a171c14;p=linux.git X.509: Fix crash caused by NULL pointer Origin: https://lore.kernel.org/linux-crypto/20210107092855.76093-1-tianjia.zhang@linux.alibaba.com/ Bug-Debian: https://bugs.debian.org/979496 On the following call path, `sig->pkey_algo` is not assigned in asymmetric_key_verify_signature(), which causes runtime crash in public_key_verify_signature(). keyctl_pkey_verify asymmetric_key_verify_signature verify_signature public_key_verify_signature This patch simply check this situation and fixes the crash caused by NULL pointer. Fixes: 215525639631 ("X.509: support OSCCA SM2-with-SM3 certificate verification") Cc: stable@vger.kernel.org # v5.10+ Reported-by: Tobias Markus Signed-off-by: Tianjia Zhang Gbp-Pq: Topic bugfix/all Gbp-Pq: Name X.509-Fix-crash-caused-by-NULL-pointer.patch --- diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c index 8892908ad58..788a4ba1e2e 100644 --- a/crypto/asymmetric_keys/public_key.c +++ b/crypto/asymmetric_keys/public_key.c @@ -356,7 +356,8 @@ 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;