6.15-stable review patch. If anyone has any objections, please let me know.
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From: Lukas Wunner lukas@wunner.de
[ Upstream commit 3828485e1c7b111290122ab6e083c2a37132b5c2 ]
KEYCTL_PKEY_QUERY system calls for ecdsa keys return the key size as max_enc_size and max_dec_size, even though such keys cannot be used for encryption/decryption. They're exclusively for signature generation or verification.
Only rsa keys with pkcs1 encoding can also be used for encryption or decryption.
Return 0 instead for ecdsa keys (as well as ecrdsa keys).
Signed-off-by: Lukas Wunner lukas@wunner.de Reviewed-by: Stefan Berger stefanb@linux.ibm.com Reviewed-by: Ignat Korchagin ignat@cloudflare.com Signed-off-by: Herbert Xu herbert@gondor.apana.org.au Stable-dep-of: 6b7f9397c98c ("crypto: ecdsa - Fix NIST P521 key size reported by KEYCTL_PKEY_QUERY") Signed-off-by: Sasha Levin sashal@kernel.org --- crypto/asymmetric_keys/public_key.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
diff --git a/crypto/asymmetric_keys/public_key.c b/crypto/asymmetric_keys/public_key.c index bf165d321440d..dd44a966947fb 100644 --- a/crypto/asymmetric_keys/public_key.c +++ b/crypto/asymmetric_keys/public_key.c @@ -188,6 +188,8 @@ static int software_key_query(const struct kernel_pkey_params *params, ptr = pkey_pack_u32(ptr, pkey->paramlen); memcpy(ptr, pkey->params, pkey->paramlen);
+ memset(info, 0, sizeof(*info)); + if (issig) { sig = crypto_alloc_sig(alg_name, 0, 0); if (IS_ERR(sig)) { @@ -211,6 +213,9 @@ static int software_key_query(const struct kernel_pkey_params *params, info->supported_ops |= KEYCTL_SUPPORTS_SIGN;
if (strcmp(params->encoding, "pkcs1") == 0) { + info->max_enc_size = len; + info->max_dec_size = len; + info->supported_ops |= KEYCTL_SUPPORTS_ENCRYPT; if (pkey->key_is_private) info->supported_ops |= KEYCTL_SUPPORTS_DECRYPT; @@ -232,6 +237,8 @@ static int software_key_query(const struct kernel_pkey_params *params, len = crypto_akcipher_maxsize(tfm); info->max_sig_size = len; info->max_data_size = len; + info->max_enc_size = len; + info->max_dec_size = len;
info->supported_ops = KEYCTL_SUPPORTS_ENCRYPT; if (pkey->key_is_private) @@ -239,8 +246,6 @@ static int software_key_query(const struct kernel_pkey_params *params, }
info->key_size = len * 8; - info->max_enc_size = len; - info->max_dec_size = len;
ret = 0;