[PATCH AUTOSEL 5.15 09/11] asymmetric_keys: log on fatal failures in PE/pkcs7

From: Sasha Levin
Date: Fri Mar 31 2023 - 21:46:00 EST


From: Robbie Harwood <rharwood@xxxxxxxxxx>

[ Upstream commit 3584c1dbfffdabf8e3dc1dd25748bb38dd01cd43 ]

These particular errors can be encountered while trying to kexec when
secureboot lockdown is in place. Without this change, even with a
signed debug build, one still needs to reboot the machine to add the
appropriate dyndbg parameters (since lockdown blocks debugfs).

Accordingly, upgrade all pr_debug() before fatal error into pr_warn().

Signed-off-by: Robbie Harwood <rharwood@xxxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
cc: Jarkko Sakkinen <jarkko@xxxxxxxxxx>
cc: Eric Biederman <ebiederm@xxxxxxxxxxxx>
cc: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
cc: keyrings@xxxxxxxxxxxxxxx
cc: linux-crypto@xxxxxxxxxxxxxxx
cc: kexec@xxxxxxxxxxxxxxxxxxx
Link: https://lore.kernel.org/r/20230220171254.592347-3-rharwood@xxxxxxxxxx/ # v2
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
crypto/asymmetric_keys/pkcs7_verify.c | 10 +++++-----
crypto/asymmetric_keys/verify_pefile.c | 24 ++++++++++++------------
2 files changed, 17 insertions(+), 17 deletions(-)

diff --git a/crypto/asymmetric_keys/pkcs7_verify.c b/crypto/asymmetric_keys/pkcs7_verify.c
index f94a1d1ad3a6c..df279538cead3 100644
--- a/crypto/asymmetric_keys/pkcs7_verify.c
+++ b/crypto/asymmetric_keys/pkcs7_verify.c
@@ -79,16 +79,16 @@ static int pkcs7_digest(struct pkcs7_message *pkcs7,
}

if (sinfo->msgdigest_len != sig->digest_size) {
- pr_debug("Sig %u: Invalid digest size (%u)\n",
- sinfo->index, sinfo->msgdigest_len);
+ pr_warn("Sig %u: Invalid digest size (%u)\n",
+ sinfo->index, sinfo->msgdigest_len);
ret = -EBADMSG;
goto error;
}

if (memcmp(sig->digest, sinfo->msgdigest,
sinfo->msgdigest_len) != 0) {
- pr_debug("Sig %u: Message digest doesn't match\n",
- sinfo->index);
+ pr_warn("Sig %u: Message digest doesn't match\n",
+ sinfo->index);
ret = -EKEYREJECTED;
goto error;
}
@@ -481,7 +481,7 @@ int pkcs7_supply_detached_data(struct pkcs7_message *pkcs7,
const void *data, size_t datalen)
{
if (pkcs7->data) {
- pr_debug("Data already supplied\n");
+ pr_warn("Data already supplied\n");
return -EINVAL;
}
pkcs7->data = data;
diff --git a/crypto/asymmetric_keys/verify_pefile.c b/crypto/asymmetric_keys/verify_pefile.c
index fe1bb374239d7..22beaf2213a22 100644
--- a/crypto/asymmetric_keys/verify_pefile.c
+++ b/crypto/asymmetric_keys/verify_pefile.c
@@ -74,7 +74,7 @@ static int pefile_parse_binary(const void *pebuf, unsigned int pelen,
break;

default:
- pr_debug("Unknown PEOPT magic = %04hx\n", pe32->magic);
+ pr_warn("Unknown PEOPT magic = %04hx\n", pe32->magic);
return -ELIBBAD;
}

@@ -95,7 +95,7 @@ static int pefile_parse_binary(const void *pebuf, unsigned int pelen,
ctx->certs_size = ddir->certs.size;

if (!ddir->certs.virtual_address || !ddir->certs.size) {
- pr_debug("Unsigned PE binary\n");
+ pr_warn("Unsigned PE binary\n");
return -ENODATA;
}

@@ -127,7 +127,7 @@ static int pefile_strip_sig_wrapper(const void *pebuf,
unsigned len;

if (ctx->sig_len < sizeof(wrapper)) {
- pr_debug("Signature wrapper too short\n");
+ pr_warn("Signature wrapper too short\n");
return -ELIBBAD;
}

@@ -142,16 +142,16 @@ static int pefile_strip_sig_wrapper(const void *pebuf,
* rounded up since 0.110.
*/
if (wrapper.length > ctx->sig_len) {
- pr_debug("Signature wrapper bigger than sig len (%x > %x)\n",
- ctx->sig_len, wrapper.length);
+ pr_warn("Signature wrapper bigger than sig len (%x > %x)\n",
+ ctx->sig_len, wrapper.length);
return -ELIBBAD;
}
if (wrapper.revision != WIN_CERT_REVISION_2_0) {
- pr_debug("Signature is not revision 2.0\n");
+ pr_warn("Signature is not revision 2.0\n");
return -ENOTSUPP;
}
if (wrapper.cert_type != WIN_CERT_TYPE_PKCS_SIGNED_DATA) {
- pr_debug("Signature certificate type is not PKCS\n");
+ pr_warn("Signature certificate type is not PKCS\n");
return -ENOTSUPP;
}

@@ -164,7 +164,7 @@ static int pefile_strip_sig_wrapper(const void *pebuf,
ctx->sig_offset += sizeof(wrapper);
ctx->sig_len -= sizeof(wrapper);
if (ctx->sig_len < 4) {
- pr_debug("Signature data missing\n");
+ pr_warn("Signature data missing\n");
return -EKEYREJECTED;
}

@@ -198,7 +198,7 @@ static int pefile_strip_sig_wrapper(const void *pebuf,
return 0;
}
not_pkcs7:
- pr_debug("Signature data not PKCS#7\n");
+ pr_warn("Signature data not PKCS#7\n");
return -ELIBBAD;
}

@@ -341,8 +341,8 @@ static int pefile_digest_pe(const void *pebuf, unsigned int pelen,
digest_size = crypto_shash_digestsize(tfm);

if (digest_size != ctx->digest_len) {
- pr_debug("Digest size mismatch (%zx != %x)\n",
- digest_size, ctx->digest_len);
+ pr_warn("Digest size mismatch (%zx != %x)\n",
+ digest_size, ctx->digest_len);
ret = -EBADMSG;
goto error_no_desc;
}
@@ -373,7 +373,7 @@ static int pefile_digest_pe(const void *pebuf, unsigned int pelen,
* PKCS#7 certificate.
*/
if (memcmp(digest, ctx->digest, ctx->digest_len) != 0) {
- pr_debug("Digest mismatch\n");
+ pr_warn("Digest mismatch\n");
ret = -EKEYREJECTED;
} else {
pr_debug("The digests match!\n");
--
2.39.2