30 May, 2018
1 commit
-
[ Upstream commit 6459ae386699a5fe0dc52cf30255f75274fa43a4 ]
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: 757932e6da6d ("PKCS#7: Handle PKCS#7 messages that contain no X.509 certs")
Signed-off-by: Eric Biggers
Signed-off-by: David Howells
Signed-off-by: Sasha Levin
Signed-off-by: Greg Kroah-Hartman
16 May, 2018
1 commit
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commit a466856e0b7ab269cdf9461886d007e88ff575b0 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: bb30b8848c85 ("crypto: af_alg - whitelist mask and type")
Signed-off-by: Eric Dumazet
Reported-by: syzbot
Cc: Stephan Mueller
Cc: Herbert Xu
Signed-off-by: David S. Miller
Signed-off-by: Greg Kroah-Hartman
02 May, 2018
1 commit
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commit eea0d3ea7546961f69f55b26714ac8fd71c7c020 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: 3cfc3b9721123 ("crypto: drbg - use aligned buffers")
Signed-off-by: Stephan Mueller
Reported-by: syzbot+75397ee3df5c70164154@syzkaller.appspotmail.com
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman
12 Apr, 2018
1 commit
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[ Upstream commit 148b974deea927f5dbb6c468af2707b488bfa2de ]
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 15.6This 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
Cc: Jakub Jelinek
Cc: Ard Biesheuvel
Signed-off-by: Arnd Bergmann
Acked-by: Ard Biesheuvel
Signed-off-by: Herbert Xu
Signed-off-by: Sasha Levin
Signed-off-by: Greg Kroah-Hartman
08 Apr, 2018
3 commits
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commit 900a081f6912a8985dc15380ec912752cb66025a 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
Cc:
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit 333e18c5cc74438f8940c7f3a8b3573748a371f9 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:
Signed-off-by: Giovanni Cabiddu
Signed-off-by: Conor McLoughlin
Reviewed-by: Stephan Mueller
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit 8c9bdab21289c211ca1ca6a5f9b7537b4a600a02 upstream.
The buffer rctx->ext contains potentially sensitive data and should
be freed with kzfree.Cc:
Fixes: 700cb3f5fe75 ("crypto: lrw - Convert to skcipher")
Reported-by: Dan Carpenter
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman
19 Mar, 2018
1 commit
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[ Upstream commit 4c0e22c90510308433272d7ba281b1eb4eda8209 ]
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
Reviewed-by: PrasannaKumar Muralidharan
Signed-off-by: Herbert Xu
Signed-off-by: Sasha Levin
Signed-off-by: Greg Kroah-Hartman
03 Mar, 2018
1 commit
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[ Upstream commit af955bf15d2c27496b0269b1f05c26f758c68314 ]
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: 7d2c3f54e6f6 ("crypto: af_alg - remove locking in async callback")
Signed-off-by: Jonathan Cameron
Reviewed-by: Stephan Mueller
Signed-off-by: Herbert Xu
Signed-off-by: Sasha Levin
Signed-off-by: Greg Kroah-Hartman
28 Feb, 2018
4 commits
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commit 29f4a67c17e19314b7d74b8569be935e6c7edf50 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: 03bb79315ddc ("PKCS#7: Handle blacklisted certificates")
Cc: # v4.12+
Signed-off-by: Eric Biggers
Signed-off-by: David Howells
Signed-off-by: Greg Kroah-Hartman -
commit 971b42c038dc83e3327872d294fe7131bab152fc 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: 6c2dc5ae4ab7 ("X.509: Extract signature digest and make self-signed cert checks earlier")
Cc: # v4.7+
Signed-off-by: Eric Biggers
Signed-off-by: David Howells
Signed-off-by: Greg Kroah-Hartman -
commit 4b34968e77ad09628cfb3c4a7daf2adc2cefc6e8 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 @sFixes: a511e1af8b12 ("KEYS: Move the point of trust determination to __key_link()")
Cc: # v4.7+
Signed-off-by: Eric Biggers
Signed-off-by: David Howells
Signed-off-by: Greg Kroah-Hartman -
commit 437499eea4291ae9621e8763a41df027c110a1ef 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 @sFixes: 6c2dc5ae4ab7 ("X.509: Extract signature digest and make self-signed cert checks earlier")
Reported-by: Paolo Valente
Cc: Paolo Valente
Cc: # v4.7+
Signed-off-by: Eric Biggers
Signed-off-by: David Howells
Signed-off-by: Greg Kroah-Hartman
22 Feb, 2018
1 commit
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commit 75f296d93bcebcfe375884ddac79e30263a31766 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
Cc: Alexander Potapenko
Cc: Eric W. Biederman
Cc: Michal Hocko
Cc: Pekka Enberg
Cc: Steven Rostedt
Cc: Tim Hansen
Cc: Vegard Nossum
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
Signed-off-by: Greg Kroah-Hartman
17 Feb, 2018
6 commits
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commit 9fa68f620041be04720d0cbfb1bd3ddfc6310b24 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
Signed-off-by: Eric Biggers
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit a208fa8f33031b9e0aba44c7d1b7e68eb0cbd29e 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
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit a16e772e664b9a261424107784804cffc8894977 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
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit fa59b92d299f2787e6bae1ff078ee0982e80211f 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
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit 841a3ff329713f796a63356fef6e2f72e4a3f6a3 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
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit cd6ed77ad5d223dc6299fb58f62e0f5267f7e2ba 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
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman
13 Feb, 2018
1 commit
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commit 5c6ac1d4f8fbdbed65dbeb8cf149d736409d16a1 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
Signed-off-by: Herbert Xu
Signed-off-by: Horia Geantă
Signed-off-by: Greg Kroah-Hartman
04 Feb, 2018
3 commits
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commit bb30b8848c85e18ca7e371d0a869e94b3e383bdf 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
Signed-off-by: Stephan Mueller
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit c013cee99d5a18aec8c71fee8f5f41369cd12595 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: 53964b9ee63b7075 ("crypto: sha3 - Add SHA-3 hash algorithm")
Signed-off-by: Ard Biesheuvel
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit b5b9007730ce1d90deaf25d7f678511550744bdc upstream.
This fixes a typo in the CRYPTO_KPP dependency of CRYPTO_ECDH.
Fixes: 3c4b23901a0c ("crypto: ecdh - Add ECDH software support")
Signed-off-by: Hauke Mehrtens
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman
17 Jan, 2018
1 commit
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commit 9a00674213a3f00394f4e3221b88f2d21fc05789 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
Signed-off-by: Eric Biggers
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman
10 Jan, 2018
2 commits
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commit d76c68109f37cb85b243a1cf0f40313afd2bae68 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
Fixes: 0496f56065e0 ("crypto: pcrypt - Add support for new AEAD interface")
Signed-off-by: Eric Biggers
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit e57121d08c38dabec15cf3e1e2ad46721af30cae 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
#include
#includeint 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
Fixes: 71ebc4d1b27d ("crypto: chacha20poly1305 - Add a ChaCha20-Poly1305 AEAD construction, RFC7539")
Signed-off-by: Eric Biggers
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman
30 Dec, 2017
4 commits
-
commit d53c5135792319e095bb126bc43b2ee98586f7fe 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: e870456d8e7c ("crypto: algif_skcipher - overhaul memory management")
Fixes: d887c52d6ae4 ("crypto: algif_aead - overhaul memory management")
Reported-by: syzbot
Signed-off-by: Stephan Mueller
Acked-by: Jonathan Cameron
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit 11edb555966ed2c66c533d17c604f9d7e580a829 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: e870456d8e7c ("crypto: algif_skcipher - overhaul memory management")
Fixes: d887c52d6ae4 ("crypto: algif_aead - overhaul memory management")
Reported-by: syzbot
Signed-off-by: Stephan Mueller
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit 9abffc6f2efe46c3564c04312e52e07622d40e51 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
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit 2b4f27c36bcd46e820ddb9a8e6fe6a63fa4250b8 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: 0cabf2af6f5a ("crypto: skcipher - Fix crash on zero-length input")
Reported-by: syzbot
Signed-off-by: Eric Biggers
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman
25 Dec, 2017
1 commit
-
[ Upstream commit 616129cc6e75fb4da6681c16c981fa82dfe5e4c7 ]
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: 700cb3f5fe75 ("crypto: lrw - Convert to skcipher")
Signed-off-by: Christophe JAILLET
Signed-off-by: Herbert Xu
Signed-off-by: Sasha Levin
Signed-off-by: Greg Kroah-Hartman
20 Dec, 2017
6 commits
-
[ Upstream commit 7aacbfcb331ceff3ac43096d563a1f93ed46e35e ]
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
Signed-off-by: Herbert Xu
Signed-off-by: Sasha Levin
Signed-off-by: Greg Kroah-Hartman -
commit 887207ed9e5812ed9239b6d07185a2d35dda91db 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: e870456d8e7c ("crypto: algif_skcipher - overhaul memory management")
Fixes: d887c52d6ae4 ("crypto: algif_aead - overhaul memory management")
Reported-by: syzbot
Signed-off-by: Eric Biggers
Reviewed-by: Stephan Mueller
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit ecaaab5649781c5a0effdaf298a925063020500e 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
#include
#includeint 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
Fixes: eb6f13eb9f81 ("[CRYPTO] salsa20_generic: Fix multi-page processing")
Signed-off-by: Eric Biggers
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit af3ff8045bbf3e32f1a448542e73abb4c8ceb6f1 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
#includeint 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 syzkaller076574/3044CPU: 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/0x96Reported-by: syzbot
Signed-off-by: Eric Biggers
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit d2890c3778b164fde587bc16583f3a1c87233ec5 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/196CPU: 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/0x96Allocated 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/0x96Fixes: 5a7de97309f5 ("crypto: rsa - return raw integers for the ASN.1 parser")
Cc: Tudor Ambarus
Signed-off-by: Eric Biggers
Reviewed-by: James Morris
Reviewed-by: David Howells
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman -
commit b32a7dc8aef1882fbf983eb354837488cc9d54dc 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: 72548b093ee3 ("crypto: algif_aead - copy AAD from src to dst")
Reported-by: syzbot
Signed-off-by: Eric Biggers
Reviewed-by: Stephan Mueller
Signed-off-by: Herbert Xu
Signed-off-by: Greg Kroah-Hartman
14 Dec, 2017
2 commits
-
commit 54c1fb39fe0495f846539ab765925b008f86801c upstream.
->pkey_algo used to be an enum, but was changed to a string by commit
4e8ae72a75aa ("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: 4e8ae72a75aa ("X.509: Make algo identifiers text instead of enum")
Signed-off-by: Eric Biggers
Signed-off-by: David Howells
Signed-off-by: Greg Kroah-Hartman -
commit 0f30cbea005bd3077bd98cd29277d7fc2699c1da 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/0x96Fixes: 42d5ec27f873 ("X.509: Add an ASN.1 decoder")
Signed-off-by: Eric Biggers
Signed-off-by: David Howells
Reviewed-by: James Morris
Signed-off-by: Greg Kroah-Hartman