Commit graph

2131 commits

Author SHA1 Message Date
Maciej S. Szmigiero af20e4eccc X.509: unpack RSA signatureValue field from BIT STRING
commit b65c32ec5a upstream.

The signatureValue field of a X.509 certificate is encoded as a BIT STRING.
For RSA signatures this BIT STRING is of so-called primitive subtype, which
contains a u8 prefix indicating a count of unused bits in the encoding.

We have to strip this prefix from signature data, just as we already do for
key data in x509_extract_key_data() function.

This wasn't noticed earlier because this prefix byte is zero for RSA key
sizes divisible by 8. Since BIT STRING is a big-endian encoding adding zero
prefixes has no bearing on its value.

The signature length, however was incorrect, which is a problem for RSA
implementations that need it to be exactly correct (like AMD CCP).

Signed-off-by: Maciej S. Szmigiero <mail@maciej.szmigiero.name>
Fixes: c26fd69fa0 ("X.509: Add a crypto key parser for binary (DER) X.509 certificates")
Cc: stable@vger.kernel.org
Signed-off-by: James Morris <james.morris@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-07-03 11:24:57 +02:00
Eric Biggers e47c1bf99a PKCS#7: fix direct verification of SignerInfo signature
[ Upstream commit 6459ae3866 ]

If none of the certificates in a SignerInfo's certificate chain match a
trusted key, nor is the last certificate signed by a trusted key, then
pkcs7_validate_trust_one() tries to check whether the SignerInfo's
signature was made directly by a trusted key.  But, it actually fails to
set the 'sig' variable correctly, so it actually verifies the last
signature seen.  That will only be the SignerInfo's signature if the
certificate chain is empty; otherwise it will actually be the last
certificate's signature.

This is not by itself a security problem, since verifying any of the
certificates in the chain should be sufficient to verify the SignerInfo.
Still, it's not working as intended so it should be fixed.

Fix it by setting 'sig' correctly for the direct verification case.

Fixes: 757932e6da ("PKCS#7: Handle PKCS#7 messages that contain no X.509 certs")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-30 07:52:01 +02:00
Eric Dumazet 1b6d0db7ed crypto: af_alg - fix possible uninit-value in alg_bind()
commit a466856e0b upstream.

syzbot reported :

BUG: KMSAN: uninit-value in alg_bind+0xe3/0xd90 crypto/af_alg.c:162

We need to check addr_len before dereferencing sa (or uaddr)

Fixes: bb30b8848c ("crypto: af_alg - whitelist mask and type")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Stephan Mueller <smueller@chronox.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-16 10:10:23 +02:00
Stephan Mueller 674d38ea18 crypto: drbg - set freed buffers to NULL
commit eea0d3ea75 upstream.

During freeing of the internal buffers used by the DRBG, set the pointer
to NULL. It is possible that the context with the freed buffers is
reused. In case of an error during initialization where the pointers
do not yet point to allocated memory, the NULL value prevents a double
free.

Cc: stable@vger.kernel.org
Fixes: 3cfc3b9721 ("crypto: drbg - use aligned buffers")
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Reported-by: syzbot+75397ee3df5c70164154@syzkaller.appspotmail.com
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-05-01 12:58:23 -07:00
Arnd Bergmann 7cae67e312 crypto: aes-generic - build with -Os on gcc-7+
[ Upstream commit 148b974dee ]

While testing other changes, I discovered that gcc-7.2.1 produces badly
optimized code for aes_encrypt/aes_decrypt. This is especially true when
CONFIG_UBSAN_SANITIZE_ALL is enabled, where it leads to extremely
large stack usage that in turn might cause kernel stack overflows:

crypto/aes_generic.c: In function 'aes_encrypt':
crypto/aes_generic.c:1371:1: warning: the frame size of 4880 bytes is larger than 2048 bytes [-Wframe-larger-than=]
crypto/aes_generic.c: In function 'aes_decrypt':
crypto/aes_generic.c:1441:1: warning: the frame size of 4864 bytes is larger than 2048 bytes [-Wframe-larger-than=]

I verified that this problem exists on all architectures that are
supported by gcc-7.2, though arm64 in particular is less affected than
the others. I also found that gcc-7.1 and gcc-8 do not show the extreme
stack usage but still produce worse code than earlier versions for this
file, apparently because of optimization passes that generally provide
a substantial improvement in object code quality but understandably fail
to find any shortcuts in the AES algorithm.

Possible workarounds include

a) disabling -ftree-pre and -ftree-sra optimizations, this was an earlier
   patch I tried, which reliably fixed the stack usage, but caused a
   serious performance regression in some versions, as later testing
   found.

b) disabling UBSAN on this file or all ciphers, as suggested by Ard
   Biesheuvel. This would lead to massively better crypto performance in
   UBSAN-enabled kernels and avoid the stack usage, but there is a concern
   over whether we should exclude arbitrary files from UBSAN at all.

c) Forcing the optimization level in a different way. Similar to a),
   but rather than deselecting specific optimization stages,
   this now uses "gcc -Os" for this file, regardless of the
   CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE/SIZE option. This is a reliable
   workaround for the stack consumption on all architecture, and I've
   retested the performance results now on x86, cycles/byte (lower is
   better) for cbc(aes-generic) with 256 bit keys:

			-O2     -Os
	gcc-6.3.1	14.9	15.1
	gcc-7.0.1	14.7	15.3
	gcc-7.1.1	15.3	14.7
	gcc-7.2.1	16.8	15.9
	gcc-8.0.0	15.5	15.6

This implements the option c) by enabling forcing -Os on all compiler
versions starting with gcc-7.1. As a workaround for PR83356, it would
only be needed for gcc-7.2+ with UBSAN enabled, but since it also shows
better performance on gcc-7.1 without UBSAN, it seems appropriate to
use the faster version here as well.

Side note: during testing, I also played with the AES code in libressl,
which had a similar performance regression from gcc-6 to gcc-7.2,
but was three times slower overall. It might be interesting to
investigate that further and possibly port the Linux implementation
into that.

Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83356
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=83651
Cc: Richard Biener <rguenther@suse.de>
Cc: Jakub Jelinek <jakub@gcc.gnu.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-12 12:32:20 +02:00
Herbert Xu c3657fd0c1 crypto: ahash - Fix early termination in hash walk
commit 900a081f69 upstream.

When we have an unaligned SG list entry where there is no leftover
aligned data, the hash walk code will incorrectly return zero as if
the entire SG list has been processed.

This patch fixes it by moving onto the next page instead.

Reported-by: Eli Cooper <elicooper@gmx.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-08 14:26:31 +02:00
Conor McLoughlin ad35fdc00a crypto: testmgr - Fix incorrect values in PKCS#1 test vector
commit 333e18c5cc upstream.

The RSA private key for the first form should have
version, prime1, prime2, exponent1, exponent2, coefficient
values 0.
With non-zero values for prime1,2, exponent 1,2 and coefficient
the Intel QAT driver will assume that values are provided for the
private key second form. This will result in signature verification
failures for modules where QAT device is present and the modules
are signed with rsa,sha256.

Cc: <stable@vger.kernel.org>
Signed-off-by: Giovanni Cabiddu <giovanni.cabiddu@intel.com>
Signed-off-by: Conor McLoughlin <conor.mcloughlin@intel.com>
Reviewed-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-08 14:26:31 +02:00
Herbert Xu 77827f3d63 crypto: lrw - Free rctx->ext with kzfree
commit 8c9bdab212 upstream.

The buffer rctx->ext contains potentially sensitive data and should
be freed with kzfree.

Cc: <stable@vger.kernel.org>
Fixes: 700cb3f5fe ("crypto: lrw - Convert to skcipher")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-04-08 14:26:31 +02:00
Pierre 90cf769aeb crypto: ecc - Fix NULL pointer deref. on no default_rng
[ Upstream commit 4c0e22c905 ]

If crypto_get_default_rng returns an error, the
function ecc_gen_privkey should return an error.
Instead, it currently tries to use the default_rng
nevertheless, thus creating a kernel panic with a
NULL pointer dereference.
Returning the error directly, as was supposedly
intended when looking at the code, fixes this.

Signed-off-by: Pierre Ducroquet <pinaraf@pinaraf.info>
Reviewed-by: PrasannaKumar Muralidharan <prasannatsmkumar@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-19 08:42:49 +01:00
Jonathan Cameron 36d0a678fb crypto: af_alg - Fix race around ctx->rcvused by making it atomic_t
[ Upstream commit af955bf15d ]

This variable was increased and decreased without any protection.
Result was an occasional misscount and negative wrap around resulting
in false resource allocation failures.

Fixes: 7d2c3f54e6 ("crypto: af_alg - remove locking in async callback")
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Reviewed-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-03-03 10:24:29 +01:00
Eric Biggers 29e76b211e PKCS#7: fix certificate blacklisting
commit 29f4a67c17 upstream.

If there is a blacklisted certificate in a SignerInfo's certificate
chain, then pkcs7_verify_sig_chain() sets sinfo->blacklisted and returns
0.  But, pkcs7_verify() fails to handle this case appropriately, as it
actually continues on to the line 'actual_ret = 0;', indicating that the
SignerInfo has passed verification.  Consequently, PKCS#7 signature
verification ignores the certificate blacklist.

Fix this by not considering blacklisted SignerInfos to have passed
verification.

Also fix the function comment with regards to when 0 is returned.

Fixes: 03bb79315d ("PKCS#7: Handle blacklisted certificates")
Cc: <stable@vger.kernel.org> # v4.12+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 10:19:39 +01:00
Eric Biggers 1a1f7f726b PKCS#7: fix certificate chain verification
commit 971b42c038 upstream.

When pkcs7_verify_sig_chain() is building the certificate chain for a
SignerInfo using the certificates in the PKCS#7 message, it is passing
the wrong arguments to public_key_verify_signature().  Consequently,
when the next certificate is supposed to be used to verify the previous
certificate, the next certificate is actually used to verify itself.

An attacker can use this bug to create a bogus certificate chain that
has no cryptographic relationship between the beginning and end.

Fortunately I couldn't quite find a way to use this to bypass the
overall signature verification, though it comes very close.  Here's the
reasoning: due to the bug, every certificate in the chain beyond the
first actually has to be self-signed (where "self-signed" here refers to
the actual key and signature; an attacker might still manipulate the
certificate fields such that the self_signed flag doesn't actually get
set, and thus the chain doesn't end immediately).  But to pass trust
validation (pkcs7_validate_trust()), either the SignerInfo or one of the
certificates has to actually be signed by a trusted key.  Since only
self-signed certificates can be added to the chain, the only way for an
attacker to introduce a trusted signature is to include a self-signed
trusted certificate.

But, when pkcs7_validate_trust_one() reaches that certificate, instead
of trying to verify the signature on that certificate, it will actually
look up the corresponding trusted key, which will succeed, and then try
to verify the *previous* certificate, which will fail.  Thus, disaster
is narrowly averted (as far as I could tell).

Fixes: 6c2dc5ae4a ("X.509: Extract signature digest and make self-signed cert checks earlier")
Cc: <stable@vger.kernel.org> # v4.7+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 10:19:39 +01:00
Eric Biggers 99b2095ac7 X.509: fix NULL dereference when restricting key with unsupported_sig
commit 4b34968e77 upstream.

The asymmetric key type allows an X.509 certificate to be added even if
its signature's hash algorithm is not available in the crypto API.  In
that case 'payload.data[asym_auth]' will be NULL.  But the key
restriction code failed to check for this case before trying to use the
signature, resulting in a NULL pointer dereference in
key_or_keyring_common() or in restrict_link_by_signature().

Fix this by returning -ENOPKG when the signature is unsupported.

Reproducer when all the CONFIG_CRYPTO_SHA512* options are disabled and
keyctl has support for the 'restrict_keyring' command:

    keyctl new_session
    keyctl restrict_keyring @s asymmetric builtin_trusted
    openssl req -new -sha512 -x509 -batch -nodes -outform der \
        | keyctl padd asymmetric desc @s

Fixes: a511e1af8b ("KEYS: Move the point of trust determination to __key_link()")
Cc: <stable@vger.kernel.org> # v4.7+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 10:19:39 +01:00
Eric Biggers dcb04cc794 X.509: fix BUG_ON() when hash algorithm is unsupported
commit 437499eea4 upstream.

The X.509 parser mishandles the case where the certificate's signature's
hash algorithm is not available in the crypto API.  In this case,
x509_get_sig_params() doesn't allocate the cert->sig->digest buffer;
this part seems to be intentional.  However,
public_key_verify_signature() is still called via
x509_check_for_self_signed(), which triggers the 'BUG_ON(!sig->digest)'.

Fix this by making public_key_verify_signature() return -ENOPKG if the
hash buffer has not been allocated.

Reproducer when all the CONFIG_CRYPTO_SHA512* options are disabled:

    openssl req -new -sha512 -x509 -batch -nodes -outform der \
        | keyctl padd asymmetric desc @s

Fixes: 6c2dc5ae4a ("X.509: Extract signature digest and make self-signed cert checks earlier")
Reported-by: Paolo Valente <paolo.valente@linaro.org>
Cc: Paolo Valente <paolo.valente@linaro.org>
Cc: <stable@vger.kernel.org> # v4.7+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-28 10:19:39 +01:00
Levin, Alexander (Sasha Levin) ae63fd26b2 kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK
commit 75f296d93b upstream.

Convert all allocations that used a NOTRACK flag to stop using it.

Link: http://lkml.kernel.org/r/20171007030159.22241-3-alexander.levin@verizon.com
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tim Hansen <devtimhansen@gmail.com>
Cc: Vegard Nossum <vegardno@ifi.uio.no>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-22 15:42:23 +01:00
Eric Biggers 2f00eb2790 crypto: hash - prevent using keyed hashes without setting key
commit 9fa68f6200 upstream.

Currently, almost none of the keyed hash algorithms check whether a key
has been set before proceeding.  Some algorithms are okay with this and
will effectively just use a key of all 0's or some other bogus default.
However, others will severely break, as demonstrated using
"hmac(sha3-512-generic)", the unkeyed use of which causes a kernel crash
via a (potentially exploitable) stack buffer overflow.

A while ago, this problem was solved for AF_ALG by pairing each hash
transform with a 'has_key' bool.  However, there are still other places
in the kernel where userspace can specify an arbitrary hash algorithm by
name, and the kernel uses it as unkeyed hash without checking whether it
is really unkeyed.  Examples of this include:

    - KEYCTL_DH_COMPUTE, via the KDF extension
    - dm-verity
    - dm-crypt, via the ESSIV support
    - dm-integrity, via the "internal hash" mode with no key given
    - drbd (Distributed Replicated Block Device)

This bug is especially bad for KEYCTL_DH_COMPUTE as that requires no
privileges to call.

Fix the bug for all users by adding a flag CRYPTO_TFM_NEED_KEY to the
->crt_flags of each hash transform that indicates whether the transform
still needs to be keyed or not.  Then, make the hash init, import, and
digest functions return -ENOKEY if the key is still needed.

The new flag also replaces the 'has_key' bool which algif_hash was
previously using, thereby simplifying the algif_hash implementation.

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:23:00 +01:00
Eric Biggers 8d906d183b crypto: hash - annotate algorithms taking optional key
commit a208fa8f33 upstream.

We need to consistently enforce that keyed hashes cannot be used without
setting the key.  To do this we need a reliable way to determine whether
a given hash algorithm is keyed or not.  AF_ALG currently does this by
checking for the presence of a ->setkey() method.  However, this is
actually slightly broken because the CRC-32 algorithms implement
->setkey() but can also be used without a key.  (The CRC-32 "key" is not
actually a cryptographic key but rather represents the initial state.
If not overridden, then a default initial state is used.)

Prepare to fix this by introducing a flag CRYPTO_ALG_OPTIONAL_KEY which
indicates that the algorithm has a ->setkey() method, but it is not
required to be called.  Then set it on all the CRC-32 algorithms.

The same also applies to the Adler-32 implementation in Lustre.

Also, the cryptd and mcryptd templates have to pass through the flag
from their underlying algorithm.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:23:00 +01:00
Eric Biggers b806c0cc4c crypto: poly1305 - remove ->setkey() method
commit a16e772e66 upstream.

Since Poly1305 requires a nonce per invocation, the Linux kernel
implementations of Poly1305 don't use the crypto API's keying mechanism
and instead expect the key and nonce as the first 32 bytes of the data.
But ->setkey() is still defined as a stub returning an error code.  This
prevents Poly1305 from being used through AF_ALG and will also break it
completely once we start enforcing that all crypto API users (not just
AF_ALG) call ->setkey() if present.

Fix it by removing crypto_poly1305_setkey(), leaving ->setkey as NULL.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:23:00 +01:00
Eric Biggers 16210524c4 crypto: mcryptd - pass through absence of ->setkey()
commit fa59b92d29 upstream.

When the mcryptd template is used to wrap an unkeyed hash algorithm,
don't install a ->setkey() method to the mcryptd instance.  This change
is necessary for mcryptd to keep working with unkeyed hash algorithms
once we start enforcing that ->setkey() is called when present.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:23:00 +01:00
Eric Biggers ed7b0af0ca crypto: cryptd - pass through absence of ->setkey()
commit 841a3ff329 upstream.

When the cryptd template is used to wrap an unkeyed hash algorithm,
don't install a ->setkey() method to the cryptd instance.  This change
is necessary for cryptd to keep working with unkeyed hash algorithms
once we start enforcing that ->setkey() is called when present.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:22:59 +01:00
Eric Biggers b8b32e2e68 crypto: hash - introduce crypto_hash_alg_has_setkey()
commit cd6ed77ad5 upstream.

Templates that use an shash spawn can use crypto_shash_alg_has_setkey()
to determine whether the underlying algorithm requires a key or not.
But there was no corresponding function for ahash spawns.  Add it.

Note that the new function actually has to support both shash and ahash
algorithms, since the ahash API can be used with either.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-16 20:22:59 +01:00
Robert Baronescu 3a570cfe78 crypto: tcrypt - fix S/G table for test_aead_speed()
commit 5c6ac1d4f8 upstream.

In case buffer length is a multiple of PAGE_SIZE,
the S/G table is incorrectly generated.
Fix this by handling buflen = k * PAGE_SIZE separately.

Signed-off-by: Robert Baronescu <robert.baronescu@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-13 10:19:49 +01:00
Stephan Mueller f41c8a0031 crypto: af_alg - whitelist mask and type
commit bb30b8848c upstream.

The user space interface allows specifying the type and mask field used
to allocate the cipher. Only a subset of the possible flags are intended
for user space. Therefore, white-list the allowed flags.

In case the user space caller uses at least one non-allowed flag, EINVAL
is returned.

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-03 17:38:51 +01:00
Ard Biesheuvel b9788e278c crypto: sha3-generic - fixes for alignment and big endian operation
commit c013cee99d upstream.

Ensure that the input is byte swabbed before injecting it into the
SHA3 transform. Use the get_unaligned() accessor for this so that
we don't perform unaligned access inadvertently on architectures
that do not support that.

Fixes: 53964b9ee6 ("crypto: sha3 - Add SHA-3 hash algorithm")
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-03 17:38:51 +01:00
Hauke Mehrtens 2992182765 crypto: ecdh - fix typo in KPP dependency of CRYPTO_ECDH
commit b5b9007730 upstream.

This fixes a typo in the CRYPTO_KPP dependency of CRYPTO_ECDH.

Fixes: 3c4b23901a ("crypto: ecdh - Add ECDH software support")
Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-02-03 17:38:48 +01:00
Eric Biggers 3662493dbd crypto: algapi - fix NULL dereference in crypto_remove_spawns()
commit 9a00674213 upstream.

syzkaller triggered a NULL pointer dereference in crypto_remove_spawns()
via a program that repeatedly and concurrently requests AEADs
"authenc(cmac(des3_ede-asm),pcbc-aes-aesni)" and hashes "cmac(des3_ede)"
through AF_ALG, where the hashes are requested as "untested"
(CRYPTO_ALG_TESTED is set in ->salg_mask but clear in ->salg_feat; this
causes the template to be instantiated for every request).

Although AF_ALG users really shouldn't be able to request an "untested"
algorithm, the NULL pointer dereference is actually caused by a
longstanding race condition where crypto_remove_spawns() can encounter
an instance which has had spawn(s) "grabbed" but hasn't yet been
registered, resulting in ->cra_users still being NULL.

We probably should properly initialize ->cra_users earlier, but that
would require updating many templates individually.  For now just fix
the bug in a simple way that can easily be backported: make
crypto_remove_spawns() treat a NULL ->cra_users list as empty.

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-17 09:45:23 +01:00
Eric Biggers 7156c794b8 crypto: pcrypt - fix freeing pcrypt instances
commit d76c68109f upstream.

pcrypt is using the old way of freeing instances, where the ->free()
method specified in the 'struct crypto_template' is passed a pointer to
the 'struct crypto_instance'.  But the crypto_instance is being
kfree()'d directly, which is incorrect because the memory was actually
allocated as an aead_instance, which contains the crypto_instance at a
nonzero offset.  Thus, the wrong pointer was being kfree()'d.

Fix it by switching to the new way to free aead_instance's where the
->free() method is specified in the aead_instance itself.

Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: 0496f56065 ("crypto: pcrypt - Add support for new AEAD interface")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-10 09:31:18 +01:00
Eric Biggers 9c36498f74 crypto: chacha20poly1305 - validate the digest size
commit e57121d08c upstream.

If the rfc7539 template was instantiated with a hash algorithm with
digest size larger than 16 bytes (POLY1305_DIGEST_SIZE), then the digest
overran the 'tag' buffer in 'struct chachapoly_req_ctx', corrupting the
subsequent memory, including 'cryptlen'.  This caused a crash during
crypto_skcipher_decrypt().

Fix it by, when instantiating the template, requiring that the
underlying hash algorithm has the digest size expected for Poly1305.

Reproducer:

    #include <linux/if_alg.h>
    #include <sys/socket.h>
    #include <unistd.h>

    int main()
    {
            int algfd, reqfd;
            struct sockaddr_alg addr = {
                    .salg_type = "aead",
                    .salg_name = "rfc7539(chacha20,sha256)",
            };
            unsigned char buf[32] = { 0 };

            algfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
            bind(algfd, (void *)&addr, sizeof(addr));
            setsockopt(algfd, SOL_ALG, ALG_SET_KEY, buf, sizeof(buf));
            reqfd = accept(algfd, 0, 0);
            write(reqfd, buf, 16);
            read(reqfd, buf, 16);
    }

Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: 71ebc4d1b2 ("crypto: chacha20poly1305 - Add a ChaCha20-Poly1305 AEAD construction, RFC7539")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-01-10 09:31:18 +01:00
Stephan Mueller f09fca41e2 crypto: af_alg - fix race accessing cipher request
commit d53c513579 upstream.

When invoking an asynchronous cipher operation, the invocation of the
callback may be performed before the subsequent operations in the
initial code path are invoked. The callback deletes the cipher request
data structure which implies that after the invocation of the
asynchronous cipher operation, this data structure must not be accessed
any more.

The setting of the return code size with the request data structure must
therefore be moved before the invocation of the asynchronous cipher
operation.

Fixes: e870456d8e ("crypto: algif_skcipher - overhaul memory management")
Fixes: d887c52d6a ("crypto: algif_aead - overhaul memory management")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-29 17:53:46 +01:00
Stephan Mueller c692698ebe crypto: af_alg - wait for data at beginning of recvmsg
commit 11edb55596 upstream.

The wait for data is a non-atomic operation that can sleep and therefore
potentially release the socket lock. The release of the socket lock
allows another thread to modify the context data structure. The waiting
operation for new data therefore must be called at the beginning of
recvmsg. This prevents a race condition where checks of the members of
the context data structure are performed by recvmsg while there is a
potential for modification of these values.

Fixes: e870456d8e ("crypto: algif_skcipher - overhaul memory management")
Fixes: d887c52d6a ("crypto: algif_aead - overhaul memory management")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-29 17:53:46 +01:00
Sebastian Andrzej Siewior 88990591f0 crypto: mcryptd - protect the per-CPU queue with a lock
commit 9abffc6f2e upstream.

mcryptd_enqueue_request() grabs the per-CPU queue struct and protects
access to it with disabled preemption. Then it schedules a worker on the
same CPU. The worker in mcryptd_queue_worker() guards access to the same
per-CPU variable with disabled preemption.

If we take CPU-hotplug into account then it is possible that between
queue_work_on() and the actual invocation of the worker the CPU goes
down and the worker will be scheduled on _another_ CPU. And here the
preempt_disable() protection does not work anymore. The easiest thing is
to add a spin_lock() to guard access to the list.

Another detail: mcryptd_queue_worker() is not processing more than
MCRYPTD_BATCH invocation in a row. If there are still items left, then
it will invoke queue_work() to proceed with more later. *I* would
suggest to simply drop that check because it does not use a system
workqueue and the workqueue is already marked as "CPU_INTENSIVE". And if
preemption is required then the scheduler should do it.
However if queue_work() is used then the work item is marked as CPU
unbound. That means it will try to run on the local CPU but it may run
on another CPU as well. Especially with CONFIG_DEBUG_WQ_FORCE_RR_CPU=y.
Again, the preempt_disable() won't work here but lock which was
introduced will help.
In order to keep work-item on the local CPU (and avoid RR) I changed it
to queue_work_on().

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-29 17:53:45 +01:00
Eric Biggers 29082870f5 crypto: skcipher - set walk.iv for zero-length inputs
commit 2b4f27c36b upstream.

All the ChaCha20 algorithms as well as the ARM bit-sliced AES-XTS
algorithms call skcipher_walk_virt(), then access the IV (walk.iv)
before checking whether any bytes need to be processed (walk.nbytes).

But if the input is empty, then skcipher_walk_virt() doesn't set the IV,
and the algorithms crash trying to use the uninitialized IV pointer.

Fix it by setting the IV earlier in skcipher_walk_virt().  Also fix it
for the AEAD walk functions.

This isn't a perfect solution because we can't actually align the IV to
->cra_alignmask unless there are bytes to process, for one because the
temporary buffer for the aligned IV is freed by skcipher_walk_done(),
which is only called when there are bytes to process.  Thus, algorithms
that require aligned IVs will still need to avoid accessing the IV when
walk.nbytes == 0.  Still, many algorithms/architectures are fine with
IVs having any alignment, and even for those that aren't, a misaligned
pointer bug is much less severe than an uninitialized pointer bug.

This change also matches the behavior of the older blkcipher_walk API.

Fixes: 0cabf2af6f ("crypto: skcipher - Fix crash on zero-length input")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-29 17:53:45 +01:00
Christophe Jaillet bd51398957 crypto: lrw - Fix an error handling path in 'create()'
[ Upstream commit 616129cc6e ]

All error handling paths 'goto err_drop_spawn' except this one.
In order to avoid some resources leak, we should do it as well here.

Fixes: 700cb3f5fe ("crypto: lrw - Convert to skcipher")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-25 14:26:25 +01:00
Robert Baronescu 6479a108b3 crypto: tcrypt - fix buffer lengths in test_aead_speed()
[ Upstream commit 7aacbfcb33 ]

Fix the way the length of the buffers used for
encryption / decryption are computed.
For e.g. in case of encryption, input buffer does not contain
an authentication tag.

Signed-off-by: Robert Baronescu <robert.baronescu@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20 10:10:26 +01:00
Eric Biggers cf1048e46d crypto: af_alg - fix NULL pointer dereference in
commit 887207ed9e upstream.

 af_alg_free_areq_sgls()

If allocating the ->tsgl member of 'struct af_alg_async_req' failed,
during cleanup we dereferenced the NULL ->tsgl pointer in
af_alg_free_areq_sgls(), because ->tsgl_entries was nonzero.

Fix it by only freeing the ->tsgl list if it is non-NULL.

This affected both algif_skcipher and algif_aead.

Fixes: e870456d8e ("crypto: algif_skcipher - overhaul memory management")
Fixes: d887c52d6a ("crypto: algif_aead - overhaul memory management")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20 10:10:17 +01:00
Eric Biggers c68b31521d crypto: salsa20 - fix blkcipher_walk API usage
commit ecaaab5649 upstream.

When asked to encrypt or decrypt 0 bytes, both the generic and x86
implementations of Salsa20 crash in blkcipher_walk_done(), either when
doing 'kfree(walk->buffer)' or 'free_page((unsigned long)walk->page)',
because walk->buffer and walk->page have not been initialized.

The bug is that Salsa20 is calling blkcipher_walk_done() even when
nothing is in 'walk.nbytes'.  But blkcipher_walk_done() is only meant to
be called when a nonzero number of bytes have been provided.

The broken code is part of an optimization that tries to make only one
call to salsa20_encrypt_bytes() to process inputs that are not evenly
divisible by 64 bytes.  To fix the bug, just remove this "optimization"
and use the blkcipher_walk API the same way all the other users do.

Reproducer:

    #include <linux/if_alg.h>
    #include <sys/socket.h>
    #include <unistd.h>

    int main()
    {
            int algfd, reqfd;
            struct sockaddr_alg addr = {
                    .salg_type = "skcipher",
                    .salg_name = "salsa20",
            };
            char key[16] = { 0 };

            algfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
            bind(algfd, (void *)&addr, sizeof(addr));
            reqfd = accept(algfd, 0, 0);
            setsockopt(algfd, SOL_ALG, ALG_SET_KEY, key, sizeof(key));
            read(reqfd, key, sizeof(key));
    }

Reported-by: syzbot <syzkaller@googlegroups.com>
Fixes: eb6f13eb9f ("[CRYPTO] salsa20_generic: Fix multi-page processing")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20 10:10:17 +01:00
Eric Biggers 902ae89f84 crypto: hmac - require that the underlying hash algorithm is unkeyed
commit af3ff8045b upstream.

Because the HMAC template didn't check that its underlying hash
algorithm is unkeyed, trying to use "hmac(hmac(sha3-512-generic))"
through AF_ALG or through KEYCTL_DH_COMPUTE resulted in the inner HMAC
being used without having been keyed, resulting in sha3_update() being
called without sha3_init(), causing a stack buffer overflow.

This is a very old bug, but it seems to have only started causing real
problems when SHA-3 support was added (requires CONFIG_CRYPTO_SHA3)
because the innermost hash's state is ->import()ed from a zeroed buffer,
and it just so happens that other hash algorithms are fine with that,
but SHA-3 is not.  However, there could be arch or hardware-dependent
hash algorithms also affected; I couldn't test everything.

Fix the bug by introducing a function crypto_shash_alg_has_setkey()
which tests whether a shash algorithm is keyed.  Then update the HMAC
template to require that its underlying hash algorithm is unkeyed.

Here is a reproducer:

    #include <linux/if_alg.h>
    #include <sys/socket.h>

    int main()
    {
        int algfd;
        struct sockaddr_alg addr = {
            .salg_type = "hash",
            .salg_name = "hmac(hmac(sha3-512-generic))",
        };
        char key[4096] = { 0 };

        algfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
        bind(algfd, (const struct sockaddr *)&addr, sizeof(addr));
        setsockopt(algfd, SOL_ALG, ALG_SET_KEY, key, sizeof(key));
    }

Here was the KASAN report from syzbot:

    BUG: KASAN: stack-out-of-bounds in memcpy include/linux/string.h:341  [inline]
    BUG: KASAN: stack-out-of-bounds in sha3_update+0xdf/0x2e0  crypto/sha3_generic.c:161
    Write of size 4096 at addr ffff8801cca07c40 by task syzkaller076574/3044

    CPU: 1 PID: 3044 Comm: syzkaller076574 Not tainted 4.14.0-mm1+ #25
    Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS  Google 01/01/2011
    Call Trace:
      __dump_stack lib/dump_stack.c:17 [inline]
      dump_stack+0x194/0x257 lib/dump_stack.c:53
      print_address_description+0x73/0x250 mm/kasan/report.c:252
      kasan_report_error mm/kasan/report.c:351 [inline]
      kasan_report+0x25b/0x340 mm/kasan/report.c:409
      check_memory_region_inline mm/kasan/kasan.c:260 [inline]
      check_memory_region+0x137/0x190 mm/kasan/kasan.c:267
      memcpy+0x37/0x50 mm/kasan/kasan.c:303
      memcpy include/linux/string.h:341 [inline]
      sha3_update+0xdf/0x2e0 crypto/sha3_generic.c:161
      crypto_shash_update+0xcb/0x220 crypto/shash.c:109
      shash_finup_unaligned+0x2a/0x60 crypto/shash.c:151
      crypto_shash_finup+0xc4/0x120 crypto/shash.c:165
      hmac_finup+0x182/0x330 crypto/hmac.c:152
      crypto_shash_finup+0xc4/0x120 crypto/shash.c:165
      shash_digest_unaligned+0x9e/0xd0 crypto/shash.c:172
      crypto_shash_digest+0xc4/0x120 crypto/shash.c:186
      hmac_setkey+0x36a/0x690 crypto/hmac.c:66
      crypto_shash_setkey+0xad/0x190 crypto/shash.c:64
      shash_async_setkey+0x47/0x60 crypto/shash.c:207
      crypto_ahash_setkey+0xaf/0x180 crypto/ahash.c:200
      hash_setkey+0x40/0x90 crypto/algif_hash.c:446
      alg_setkey crypto/af_alg.c:221 [inline]
      alg_setsockopt+0x2a1/0x350 crypto/af_alg.c:254
      SYSC_setsockopt net/socket.c:1851 [inline]
      SyS_setsockopt+0x189/0x360 net/socket.c:1830
      entry_SYSCALL_64_fastpath+0x1f/0x96

Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20 10:10:17 +01:00
Eric Biggers 80dbdc5ae7 crypto: rsa - fix buffer overread when stripping leading zeroes
commit d2890c3778 upstream.

In rsa_get_n(), if the buffer contained all 0's and "FIPS mode" is
enabled, we would read one byte past the end of the buffer while
scanning the leading zeroes.  Fix it by checking 'n_sz' before '!*ptr'.

This bug was reachable by adding a specially crafted key of type
"asymmetric" (requires CONFIG_RSA and CONFIG_X509_CERTIFICATE_PARSER).

KASAN report:

    BUG: KASAN: slab-out-of-bounds in rsa_get_n+0x19e/0x1d0 crypto/rsa_helper.c:33
    Read of size 1 at addr ffff88003501a708 by task keyctl/196

    CPU: 1 PID: 196 Comm: keyctl Not tainted 4.14.0-09238-g1d3b78bbc6e9 #26
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014
    Call Trace:
     rsa_get_n+0x19e/0x1d0 crypto/rsa_helper.c:33
     asn1_ber_decoder+0x82a/0x1fd0 lib/asn1_decoder.c:328
     rsa_set_pub_key+0xd3/0x320 crypto/rsa.c:278
     crypto_akcipher_set_pub_key ./include/crypto/akcipher.h:364 [inline]
     pkcs1pad_set_pub_key+0xae/0x200 crypto/rsa-pkcs1pad.c:117
     crypto_akcipher_set_pub_key ./include/crypto/akcipher.h:364 [inline]
     public_key_verify_signature+0x270/0x9d0 crypto/asymmetric_keys/public_key.c:106
     x509_check_for_self_signed+0x2ea/0x480 crypto/asymmetric_keys/x509_public_key.c:141
     x509_cert_parse+0x46a/0x620 crypto/asymmetric_keys/x509_cert_parser.c:129
     x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174
     asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388
     key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850
     SYSC_add_key security/keys/keyctl.c:122 [inline]
     SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62
     entry_SYSCALL_64_fastpath+0x1f/0x96

    Allocated by task 196:
     __do_kmalloc mm/slab.c:3711 [inline]
     __kmalloc_track_caller+0x118/0x2e0 mm/slab.c:3726
     kmemdup+0x17/0x40 mm/util.c:118
     kmemdup ./include/linux/string.h:414 [inline]
     x509_cert_parse+0x2cb/0x620 crypto/asymmetric_keys/x509_cert_parser.c:106
     x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174
     asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388
     key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850
     SYSC_add_key security/keys/keyctl.c:122 [inline]
     SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62
     entry_SYSCALL_64_fastpath+0x1f/0x96

Fixes: 5a7de97309 ("crypto: rsa - return raw integers for the ASN.1 parser")
Cc: Tudor Ambarus <tudor-dan.ambarus@nxp.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Reviewed-by: David Howells <dhowells@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20 10:10:17 +01:00
Eric Biggers 96c2dfaebe crypto: algif_aead - fix reference counting of null skcipher
commit b32a7dc8ae upstream.

In the AEAD interface for AF_ALG, the reference to the "null skcipher"
held by each tfm was being dropped in the wrong place -- when each
af_alg_ctx was freed instead of when the aead_tfm was freed.  As
discovered by syzkaller, a specially crafted program could use this to
cause the null skcipher to be freed while it is still in use.

Fix it by dropping the reference in the right place.

Fixes: 72548b093e ("crypto: algif_aead - copy AAD from src to dst")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-20 10:10:16 +01:00
Eric Biggers 70feeaaabf X.509: fix comparisons of ->pkey_algo
commit 54c1fb39fe upstream.

->pkey_algo used to be an enum, but was changed to a string by commit
4e8ae72a75 ("X.509: Make algo identifiers text instead of enum").  But
two comparisons were not updated.  Fix them to use strcmp().

This bug broke signature verification in certain configurations,
depending on whether the string constants were deduplicated or not.

Fixes: 4e8ae72a75 ("X.509: Make algo identifiers text instead of enum")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-14 09:52:53 +01:00
Eric Biggers 31b3bcc66f X.509: reject invalid BIT STRING for subjectPublicKey
commit 0f30cbea00 upstream.

Adding a specially crafted X.509 certificate whose subjectPublicKey
ASN.1 value is zero-length caused x509_extract_key_data() to set the
public key size to SIZE_MAX, as it subtracted the nonexistent BIT STRING
metadata byte.  Then, x509_cert_parse() called kmemdup() with that bogus
size, triggering the WARN_ON_ONCE() in kmalloc_slab().

This appears to be harmless, but it still must be fixed since WARNs are
never supposed to be user-triggerable.

Fix it by updating x509_cert_parse() to validate that the value has a
BIT STRING metadata byte, and that the byte is 0 which indicates that
the number of bits in the bitstring is a multiple of 8.

It would be nice to handle the metadata byte in asn1_ber_decoder()
instead.  But that would be tricky because in the general case a BIT
STRING could be implicitly tagged, and/or could legitimately have a
length that is not a whole number of bytes.

Here was the WARN (cleaned up slightly):

    WARNING: CPU: 1 PID: 202 at mm/slab_common.c:971 kmalloc_slab+0x5d/0x70 mm/slab_common.c:971
    Modules linked in:
    CPU: 1 PID: 202 Comm: keyctl Tainted: G    B            4.14.0-09238-g1d3b78bbc6e9 #26
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.11.0-20171110_100015-anatol 04/01/2014
    task: ffff880033014180 task.stack: ffff8800305c8000
    Call Trace:
     __do_kmalloc mm/slab.c:3706 [inline]
     __kmalloc_track_caller+0x22/0x2e0 mm/slab.c:3726
     kmemdup+0x17/0x40 mm/util.c:118
     kmemdup include/linux/string.h:414 [inline]
     x509_cert_parse+0x2cb/0x620 crypto/asymmetric_keys/x509_cert_parser.c:106
     x509_key_preparse+0x61/0x750 crypto/asymmetric_keys/x509_public_key.c:174
     asymmetric_key_preparse+0xa4/0x150 crypto/asymmetric_keys/asymmetric_type.c:388
     key_create_or_update+0x4d4/0x10a0 security/keys/key.c:850
     SYSC_add_key security/keys/keyctl.c:122 [inline]
     SyS_add_key+0xe8/0x290 security/keys/keyctl.c:62
     entry_SYSCALL_64_fastpath+0x1f/0x96

Fixes: 42d5ec27f8 ("X.509: Add an ASN.1 decoder")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: James Morris <james.l.morris@oracle.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-14 09:52:53 +01:00
Ondrej Mosnáček 861eae231b crypto: skcipher - Fix skcipher_walk_aead_common
commit c14ca83865 upstream.

The skcipher_walk_aead_common function calls scatterwalk_copychunks on
the input and output walks to skip the associated data. If the AD end
at an SG list entry boundary, then after these calls the walks will
still be pointing to the end of the skipped region.

These offsets are later checked for alignment in skcipher_walk_next,
so the skcipher_walk may detect the alignment incorrectly.

This patch fixes it by calling scatterwalk_done after the copychunks
calls to ensure that the offsets refer to the right SG list entry.

Fixes: b286d8b1a6 ("crypto: skcipher - Add skcipher walk interface")
Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-05 11:26:30 +01:00
Stephan Mueller 7f21961a2d crypto: af_alg - remove locking in async callback
commit 7d2c3f54e6 upstream.

The code paths protected by the socket-lock do not use or modify the
socket in a non-atomic fashion. The actions pertaining the socket do not
even need to be handled as an atomic operation. Thus, the socket-lock
can be safely ignored.

This fixes a bug regarding scheduling in atomic as the callback function
may be invoked in interrupt context.

In addition, the sock_hold is moved before the AIO encrypt/decrypt
operation to ensure that the socket is always present. This avoids a
tiny race window where the socket is unprotected and yet used by the AIO
operation.

Finally, the release of resources for a crypto operation is moved into a
common function of af_alg_free_resources.

Fixes: e870456d8e ("crypto: algif_skcipher - overhaul memory management")
Fixes: d887c52d6a ("crypto: algif_aead - overhaul memory management")
Reported-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Tested-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-05 11:26:30 +01:00
Stephan Mueller 721872a199 crypto: algif_aead - skip SGL entries with NULL page
commit 8e1fa89aa8 upstream.

The TX SGL may contain SGL entries that are assigned a NULL page. This
may happen if a multi-stage AIO operation is performed where the data
for each stage is pointed to by one SGL entry. Upon completion of that
stage, af_alg_pull_tsgl will assign NULL to the SGL entry.

The NULL cipher used to copy the AAD from TX SGL to the destination
buffer, however, cannot handle the case where the SGL starts with an SGL
entry having a NULL page. Thus, the code needs to advance the start
pointer into the SGL to the first non-NULL entry.

This fixes a crash visible on Intel x86 32 bit using the libkcapi test
suite.

Fixes: 72548b093e ("crypto: algif_aead - copy AAD from src to dst")
Signed-off-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-12-05 11:26:30 +01:00
Eric Biggers 5e56be0e26 crypto: dh - Don't permit 'key' or 'g' size longer than 'p'
commit ccd9888f14 upstream.

The "qat-dh" DH implementation assumes that 'key' and 'g' can be copied
into a buffer with size 'p_size'.  However it was never checked that
that was actually the case, which most likely allowed users to cause a
buffer underflow via KEYCTL_DH_COMPUTE.

Fix this by updating crypto_dh_decode_key() to verify this precondition
for all DH implementations.

Fixes: c9839143eb ("crypto: qat - Add DH support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-21 09:49:21 +01:00
Eric Biggers 716b9ea8c6 crypto: dh - Don't permit 'p' to be 0
commit 199512b123 upstream.

If 'p' is 0 for the software Diffie-Hellman implementation, then
dh_max_size() returns 0.  In the case of KEYCTL_DH_COMPUTE, this causes
ZERO_SIZE_PTR to be passed to sg_init_one(), which with
CONFIG_DEBUG_SG=y triggers the 'BUG_ON(!virt_addr_valid(buf));' in
sg_set_buf().

Fix this by making crypto_dh_decode_key() reject 0 for 'p'.  p=0 makes
no sense for any DH implementation because 'p' is supposed to be a prime
number.  Moreover, 'mod 0' is not mathematically defined.

Bug report:

    kernel BUG at ./include/linux/scatterlist.h:140!
    invalid opcode: 0000 [#1] SMP KASAN
    CPU: 0 PID: 27112 Comm: syz-executor2 Not tainted 4.14.0-rc7-00010-gf5dbb5d0ce32-dirty #7
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.10.3-20171021_125229-anatol 04/01/2014
    task: ffff88006caac0c0 task.stack: ffff88006c7c8000
    RIP: 0010:sg_set_buf include/linux/scatterlist.h:140 [inline]
    RIP: 0010:sg_init_one+0x1b3/0x240 lib/scatterlist.c:156
    RSP: 0018:ffff88006c7cfb08 EFLAGS: 00010216
    RAX: 0000000000010000 RBX: ffff88006c7cfe30 RCX: 00000000000064ee
    RDX: ffffffff81cf64c3 RSI: ffffc90000d72000 RDI: ffffffff92e937e0
    RBP: ffff88006c7cfb30 R08: ffffed000d8f9fab R09: ffff88006c7cfd30
    R10: 0000000000000005 R11: ffffed000d8f9faa R12: ffff88006c7cfd30
    R13: 0000000000000000 R14: 0000000000000010 R15: ffff88006c7cfc50
    FS:  00007fce190fa700(0000) GS:ffff88003ea00000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: 00007fffc6b33db8 CR3: 000000003cf64000 CR4: 00000000000006f0
    Call Trace:
     __keyctl_dh_compute+0xa95/0x19b0 security/keys/dh.c:360
     keyctl_dh_compute+0xac/0x100 security/keys/dh.c:434
     SYSC_keyctl security/keys/keyctl.c:1745 [inline]
     SyS_keyctl+0x72/0x2c0 security/keys/keyctl.c:1641
     entry_SYSCALL_64_fastpath+0x1f/0xbe
    RIP: 0033:0x4585c9
    RSP: 002b:00007fce190f9bd8 EFLAGS: 00000216 ORIG_RAX: 00000000000000fa
    RAX: ffffffffffffffda RBX: 0000000000738020 RCX: 00000000004585c9
    RDX: 000000002000d000 RSI: 0000000020000ff4 RDI: 0000000000000017
    RBP: 0000000000000046 R08: 0000000020008000 R09: 0000000000000000
    R10: 0000000000000000 R11: 0000000000000216 R12: 00007fff6e610cde
    R13: 00007fff6e610cdf R14: 00007fce190fa700 R15: 0000000000000000
    Code: 03 0f b6 14 02 48 89 f8 83 e0 07 83 c0 03 38 d0 7c 04 84 d2 75 33 5b 45 89 6c 24 14 41 5c 41 5d 41 5e 41 5f 5d c3 e8 fd 8f 68 ff <0f> 0b e8 f6 8f 68 ff 0f 0b e8 ef 8f 68 ff 0f 0b e8 e8 8f 68 ff 20
    RIP: sg_set_buf include/linux/scatterlist.h:140 [inline] RSP: ffff88006c7cfb08
    RIP: sg_init_one+0x1b3/0x240 lib/scatterlist.c:156 RSP: ffff88006c7cfb08

Fixes: 802c7f1c84 ("crypto: dh - Add DH software implementation")
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-21 09:49:21 +01:00
Eric Biggers a37b2a1cc6 crypto: dh - Fix double free of ctx->p
commit 12d41a023e upstream.

When setting the secret with the software Diffie-Hellman implementation,
if allocating 'g' failed (e.g. if it was longer than
MAX_EXTERN_MPI_BITS), then 'p' was freed twice: once immediately, and
once later when the crypto_kpp tfm was destroyed.

Fix it by using dh_free_ctx() (renamed to dh_clear_ctx()) in the error
paths, as that correctly sets the pointers to NULL.

KASAN report:

    MPI: mpi too large (32760 bits)
    ==================================================================
    BUG: KASAN: use-after-free in mpi_free+0x131/0x170
    Read of size 4 at addr ffff88006c7cdf90 by task reproduce_doubl/367

    CPU: 1 PID: 367 Comm: reproduce_doubl Not tainted 4.14.0-rc7-00040-g05298abde6fe #7
    Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS Bochs 01/01/2011
    Call Trace:
     dump_stack+0xb3/0x10b
     ? mpi_free+0x131/0x170
     print_address_description+0x79/0x2a0
     ? mpi_free+0x131/0x170
     kasan_report+0x236/0x340
     ? akcipher_register_instance+0x90/0x90
     __asan_report_load4_noabort+0x14/0x20
     mpi_free+0x131/0x170
     ? akcipher_register_instance+0x90/0x90
     dh_exit_tfm+0x3d/0x140
     crypto_kpp_exit_tfm+0x52/0x70
     crypto_destroy_tfm+0xb3/0x250
     __keyctl_dh_compute+0x640/0xe90
     ? kasan_slab_free+0x12f/0x180
     ? dh_data_from_key+0x240/0x240
     ? key_create_or_update+0x1ee/0xb20
     ? key_instantiate_and_link+0x440/0x440
     ? lock_contended+0xee0/0xee0
     ? kfree+0xcf/0x210
     ? SyS_add_key+0x268/0x340
     keyctl_dh_compute+0xb3/0xf1
     ? __keyctl_dh_compute+0xe90/0xe90
     ? SyS_add_key+0x26d/0x340
     ? entry_SYSCALL_64_fastpath+0x5/0xbe
     ? trace_hardirqs_on_caller+0x3f4/0x560
     SyS_keyctl+0x72/0x2c0
     entry_SYSCALL_64_fastpath+0x1f/0xbe
    RIP: 0033:0x43ccf9
    RSP: 002b:00007ffeeec96158 EFLAGS: 00000246 ORIG_RAX: 00000000000000fa
    RAX: ffffffffffffffda RBX: 000000000248b9b9 RCX: 000000000043ccf9
    RDX: 00007ffeeec96170 RSI: 00007ffeeec96160 RDI: 0000000000000017
    RBP: 0000000000000046 R08: 0000000000000000 R09: 0248b9b9143dc936
    R10: 0000000000001000 R11: 0000000000000246 R12: 0000000000000000
    R13: 0000000000409670 R14: 0000000000409700 R15: 0000000000000000

    Allocated by task 367:
     save_stack_trace+0x16/0x20
     kasan_kmalloc+0xeb/0x180
     kmem_cache_alloc_trace+0x114/0x300
     mpi_alloc+0x4b/0x230
     mpi_read_raw_data+0xbe/0x360
     dh_set_secret+0x1dc/0x460
     __keyctl_dh_compute+0x623/0xe90
     keyctl_dh_compute+0xb3/0xf1
     SyS_keyctl+0x72/0x2c0
     entry_SYSCALL_64_fastpath+0x1f/0xbe

    Freed by task 367:
     save_stack_trace+0x16/0x20
     kasan_slab_free+0xab/0x180
     kfree+0xb5/0x210
     mpi_free+0xcb/0x170
     dh_set_secret+0x2d7/0x460
     __keyctl_dh_compute+0x623/0xe90
     keyctl_dh_compute+0xb3/0xf1
     SyS_keyctl+0x72/0x2c0
     entry_SYSCALL_64_fastpath+0x1f/0xbe

Fixes: 802c7f1c84 ("crypto: dh - Add DH software implementation")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-21 09:49:20 +01:00
Linus Torvalds af903dcd31 Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
Pull crypto fixes from Herbert Xu:
 "This fixes an unaligned panic in x86/sha-mb and a bug in ccm that
  triggers with certain underlying implementations"

* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: ccm - preserve the IV buffer
  crypto: x86/sha1-mb - fix panic due to unaligned access
  crypto: x86/sha256-mb - fix panic due to unaligned access
2017-11-06 09:05:03 -08:00
Romain Izard 441f99c904 crypto: ccm - preserve the IV buffer
The IV buffer used during CCM operations is used twice, during both the
hashing step and the ciphering step.

When using a hardware accelerator that updates the contents of the IV
buffer at the end of ciphering operations, the value will be modified.
In the decryption case, the subsequent setup of the hashing algorithm
will interpret the updated IV instead of the original value, which can
lead to out-of-bounds writes.

Reuse the idata buffer, only used in the hashing step, to preserve the
IV's value during the ciphering step in the decryption case.

Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-03 21:35:35 +08:00
Greg Kroah-Hartman b24413180f License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.

By default all files without license information are under the default
license of the kernel, which is GPL version 2.

Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier.  The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.

This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.

How this work was done:

Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
 - file had no licensing information it it.
 - file was a */uapi/* one with no licensing information in it,
 - file was a */uapi/* one with existing licensing information,

Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.

The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne.  Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.

The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed.  Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.

Criteria used to select files for SPDX license identifier tagging was:
 - Files considered eligible had to be source code files.
 - Make and config files were included as candidates if they contained >5
   lines of source
 - File already had some variant of a license header in it (even if <5
   lines).

All documentation files were explicitly excluded.

The following heuristics were used to determine which SPDX license
identifiers to apply.

 - when both scanners couldn't find any license traces, file was
   considered to have no license information in it, and the top level
   COPYING file license applied.

   For non */uapi/* files that summary was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0                                              11139

   and resulted in the first patch in this series.

   If that file was a */uapi/* path one, it was "GPL-2.0 WITH
   Linux-syscall-note" otherwise it was "GPL-2.0".  Results of that was:

   SPDX license identifier                            # files
   ---------------------------------------------------|-------
   GPL-2.0 WITH Linux-syscall-note                        930

   and resulted in the second patch in this series.

 - if a file had some form of licensing information in it, and was one
   of the */uapi/* ones, it was denoted with the Linux-syscall-note if
   any GPL family license was found in the file or had no licensing in
   it (per prior point).  Results summary:

   SPDX license identifier                            # files
   ---------------------------------------------------|------
   GPL-2.0 WITH Linux-syscall-note                       270
   GPL-2.0+ WITH Linux-syscall-note                      169
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause)    21
   ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause)    17
   LGPL-2.1+ WITH Linux-syscall-note                      15
   GPL-1.0+ WITH Linux-syscall-note                       14
   ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause)    5
   LGPL-2.0+ WITH Linux-syscall-note                       4
   LGPL-2.1 WITH Linux-syscall-note                        3
   ((GPL-2.0 WITH Linux-syscall-note) OR MIT)              3
   ((GPL-2.0 WITH Linux-syscall-note) AND MIT)             1

   and that resulted in the third patch in this series.

 - when the two scanners agreed on the detected license(s), that became
   the concluded license(s).

 - when there was disagreement between the two scanners (one detected a
   license but the other didn't, or they both detected different
   licenses) a manual inspection of the file occurred.

 - In most cases a manual inspection of the information in the file
   resulted in a clear resolution of the license that should apply (and
   which scanner probably needed to revisit its heuristics).

 - When it was not immediately clear, the license identifier was
   confirmed with lawyers working with the Linux Foundation.

 - If there was any question as to the appropriate license identifier,
   the file was flagged for further research and to be revisited later
   in time.

In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.

Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights.  The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.

Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.

In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.

Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
 - a full scancode scan run, collecting the matched texts, detected
   license ids and scores
 - reviewing anything where there was a license detected (about 500+
   files) to ensure that the applied SPDX license was correct
 - reviewing anything where there was no detection but the patch license
   was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
   SPDX license was correct

This produced a worksheet with 20 files needing minor correction.  This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.

These .csv files were then reviewed by Greg.  Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected.  This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.)  Finally Greg ran the script using the .csv files to
generate the patches.

Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-02 11:10:55 +01:00