Commit graph

1,218 commits

Author SHA1 Message Date
Eric Biggers
d1bc1078ee crypto: ahash - fix another early termination in hash walk
commit 77568e535a upstream.

Hash algorithms with an alignmask set, e.g. "xcbc(aes-aesni)" and
"michael_mic", fail the improved hash tests because they sometimes
produce the wrong digest.  The bug is that in the case where a
scatterlist element crosses pages, not all the data is actually hashed
because the scatterlist walk terminates too early.  This happens because
the 'nbytes' variable in crypto_hash_walk_done() is assigned the number
of bytes remaining in the page, then later interpreted as the number of
bytes remaining in the scatterlist element.  Fix it.

Fixes: 900a081f69 ("crypto: ahash - Fix early termination in hash walk")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:03:55 +01:00
Eric Biggers
a67f0130ea crypto: testmgr - skip crc32c context test for ahash algorithms
commit eb5e6730db upstream.

Instantiating "cryptd(crc32c)" causes a crypto self-test failure because
the crypto_alloc_shash() in alg_test_crc32c() fails.  This is because
cryptd(crc32c) is an ahash algorithm, not a shash algorithm; so it can
only be accessed through the ahash API, unlike shash algorithms which
can be accessed through both the ahash and shash APIs.

As the test is testing the shash descriptor format which is only
applicable to shash algorithms, skip it for ahash algorithms.

(Note that it's still important to fix crypto self-test failures even
 for weird algorithm instantiations like cryptd(crc32c) that no one
 would really use; in fips_enabled mode unprivileged users can use them
 to panic the kernel, and also they prevent treating a crypto self-test
 failure as a bug when fuzzing the kernel.)

Fixes: 8e3ee85e68 ("crypto: crc32c - Test descriptor context format")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:03:52 +01:00
Eric Biggers
7eadb226ba crypto: tgr192 - fix unaligned memory access
commit f990f7fb58 upstream.

Fix an unaligned memory access in tgr192_transform() by using the
unaligned access helpers.

Fixes: 06ace7a9ba ("[CRYPTO] Use standard byte order macros wherever possible")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:03:48 +01:00
Eric Biggers
9aa2d96df4 crypto: hash - set CRYPTO_TFM_NEED_KEY if ->setkey() fails
commit ba7d7433a0 upstream.

Some algorithms have a ->setkey() method that is not atomic, in the
sense that setting a key can fail after changes were already made to the
tfm context.  In this case, if a key was already set the tfm can end up
in a state that corresponds to neither the old key nor the new key.

It's not feasible to make all ->setkey() methods atomic, especially ones
that have to key multiple sub-tfms.  Therefore, make the crypto API set
CRYPTO_TFM_NEED_KEY if ->setkey() fails and the algorithm requires a
key, to prevent the tfm from being used until a new key is set.

Note: we can't set CRYPTO_TFM_NEED_KEY for OPTIONAL_KEY algorithms, so
->setkey() for those must nevertheless be atomic.  That's fine for now
since only the crc32 and crc32c algorithms set OPTIONAL_KEY, and it's
not intended that OPTIONAL_KEY be used much.

[Cc stable mainly because when introducing the NEED_KEY flag I changed
 AF_ALG to rely on it; and unlike in-kernel crypto API users, AF_ALG
 previously didn't have this problem.  So these "incompletely keyed"
 states became theoretically accessible via AF_ALG -- though, the
 opportunities for causing real mischief seem pretty limited.]

Fixes: 9fa68f6200 ("crypto: hash - prevent using keyed hashes without setting key")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:03:48 +01:00
Eric Biggers
ddc5662004 crypto: pcbc - remove bogus memcpy()s with src == dest
commit 251b7aea34 upstream.

The memcpy()s in the PCBC implementation use walk->iv as both the source
and destination, which has undefined behavior.  These memcpy()'s are
actually unneeded, because walk->iv is already used to hold the previous
plaintext block XOR'd with the previous ciphertext block.  Thus,
walk->iv is already updated to its final value.

So remove the broken and unnecessary memcpy()s.

Fixes: 91652be5d1 ("[CRYPTO] pcbc: Add Propagated CBC template")
Cc: David Howells <dhowells@redhat.com>
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-07-09 22:03:46 +01:00
Eric Biggers
ccd67cd15b crypto: authenc - fix parsing key with misaligned rta_len
commit 8f9c469348 upstream.

Keys for "authenc" AEADs are formatted as an rtattr containing a 4-byte
'enckeylen', followed by an authentication key and an encryption key.
crypto_authenc_extractkeys() parses the key to find the inner keys.

However, it fails to consider the case where the rtattr's payload is
longer than 4 bytes but not 4-byte aligned, and where the key ends
before the next 4-byte aligned boundary.  In this case, 'keylen -=
RTA_ALIGN(rta->rta_len);' underflows to a value near UINT_MAX.  This
causes a buffer overread and crash during crypto_ahash_setkey().

Fix it by restricting the rtattr payload to the expected size.

Reproducer using AF_ALG:

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

	int main()
	{
		int fd;
		struct sockaddr_alg addr = {
			.salg_type = "aead",
			.salg_name = "authenc(hmac(sha256),cbc(aes))",
		};
		struct {
			struct rtattr attr;
			__be32 enckeylen;
			char keys[1];
		} __attribute__((packed)) key = {
			.attr.rta_len = sizeof(key),
			.attr.rta_type = 1 /* CRYPTO_AUTHENC_KEYA_PARAM */,
		};

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

It caused:

	BUG: unable to handle kernel paging request at ffff88007ffdc000
	PGD 2e01067 P4D 2e01067 PUD 2e04067 PMD 2e05067 PTE 0
	Oops: 0000 [#1] SMP
	CPU: 0 PID: 883 Comm: authenc Not tainted 4.20.0-rc1-00108-g00c9fe37a7f27 #13
	Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-20181126_142135-anatol 04/01/2014
	RIP: 0010:sha256_ni_transform+0xb3/0x330 arch/x86/crypto/sha256_ni_asm.S:155
	[...]
	Call Trace:
	 sha256_ni_finup+0x10/0x20 arch/x86/crypto/sha256_ssse3_glue.c:321
	 crypto_shash_finup+0x1a/0x30 crypto/shash.c:178
	 shash_digest_unaligned+0x45/0x60 crypto/shash.c:186
	 crypto_shash_digest+0x24/0x40 crypto/shash.c:202
	 hmac_setkey+0x135/0x1e0 crypto/hmac.c:66
	 crypto_shash_setkey+0x2b/0xb0 crypto/shash.c:66
	 shash_async_setkey+0x10/0x20 crypto/shash.c:223
	 crypto_ahash_setkey+0x2d/0xa0 crypto/ahash.c:202
	 crypto_authenc_setkey+0x68/0x100 crypto/authenc.c:96
	 crypto_aead_setkey+0x2a/0xc0 crypto/aead.c:62
	 aead_setkey+0xc/0x10 crypto/algif_aead.c:526
	 alg_setkey crypto/af_alg.c:223 [inline]
	 alg_setsockopt+0xfe/0x130 crypto/af_alg.c:256
	 __sys_setsockopt+0x6d/0xd0 net/socket.c:1902
	 __do_sys_setsockopt net/socket.c:1913 [inline]
	 __se_sys_setsockopt net/socket.c:1910 [inline]
	 __x64_sys_setsockopt+0x1f/0x30 net/socket.c:1910
	 do_syscall_64+0x4a/0x180 arch/x86/entry/common.c:290
	 entry_SYSCALL_64_after_hwframe+0x49/0xbe

Fixes: e236d4a89a ("[CRYPTO] authenc: Move enckeylen into key itself")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-05-02 21:41:18 +01:00
Eric Biggers
e6f5929864 crypto: user - support incremental algorithm dumps
commit 0ac6b8fb23 upstream.

CRYPTO_MSG_GETALG in NLM_F_DUMP mode sometimes doesn't return all
registered crypto algorithms, because it doesn't support incremental
dumps.  crypto_dump_report() only permits itself to be called once, yet
the netlink subsystem allocates at most ~64 KiB for the skb being dumped
to.  Thus only the first recvmsg() returns data, and it may only include
a subset of the crypto algorithms even if the user buffer passed to
recvmsg() is large enough to hold all of them.

Fix this by using one of the arguments in the netlink_callback structure
to keep track of the current position in the algorithm list.  Then
userspace can do multiple recvmsg() on the socket after sending the dump
request.  This is the way netlink dumps work elsewhere in the kernel;
it's unclear why this was different (probably just an oversight).

Also fix an integer overflow when calculating the dump buffer size hint.

Fixes: a38f7907b9 ("crypto: Add userspace configuration API")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-04-04 16:13:49 +01:00
Colin Ian King
8c9874721f pcrypt: use format specifier in kobject_add
commit b1e3874c75 upstream.

Passing string 'name' as the format specifier is potentially hazardous
because name could (although very unlikely to) have a format specifier
embedded in it causing issues when parsing the non-existent arguments
to these.  Follow best practice by using the "%s" format string for
the string 'name'.

Cleans up clang warning:
crypto/pcrypt.c:397:40: warning: format string is not a string literal
(potentially insecure) [-Wformat-security]

Fixes: a3fb1e330d ("pcrypt: Added sysfs interface to pcrypt")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-04-04 16:13:40 +01:00
Ondrej Mosnacek
175aa81c87 crypto: lrw - Fix out-of bounds access on counter overflow
commit fbe1a850b3 upstream.

When the LRW block counter overflows, the current implementation returns
128 as the index to the precomputed multiplication table, which has 128
entries. This patch fixes it to return the correct value (127).

Fixes: 64470f1b85 ("[CRYPTO] lrw: Liskov Rivest Wagner, a tweakable narrow block cipher mode")
Reported-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Ondrej Mosnacek <omosnace@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2019-02-11 17:53:22 +00:00
Eric Biggers
f3963877fb crypto: ablkcipher - fix crash flushing dcache in error path
commit 318abdfbe7 upstream.

Like the skcipher_walk and blkcipher_walk cases:

scatterwalk_done() is only meant to be called after a nonzero number of
bytes have been processed, since scatterwalk_pagedone() will flush the
dcache of the *previous* page.  But in the error case of
ablkcipher_walk_done(), e.g. if the input wasn't an integer number of
blocks, scatterwalk_done() was actually called after advancing 0 bytes.
This caused a crash ("BUG: unable to handle kernel paging request")
during '!PageSlab(page)' on architectures like arm and arm64 that define
ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE, provided that the input was
page-aligned as in that case walk->offset == 0.

Fix it by reorganizing ablkcipher_walk_done() to skip the
scatterwalk_advance() and scatterwalk_done() if an error has occurred.

Reported-by: Liu Chao <liuchao741@huawei.com>
Fixes: bf06099db1 ("crypto: skcipher - Add ablkcipher_walk interfaces")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-12-16 22:08:34 +00:00
Eric Biggers
63d208ad1e crypto: blkcipher - fix crash flushing dcache in error path
commit 0868def3e4 upstream.

Like the skcipher_walk case:

scatterwalk_done() is only meant to be called after a nonzero number of
bytes have been processed, since scatterwalk_pagedone() will flush the
dcache of the *previous* page.  But in the error case of
blkcipher_walk_done(), e.g. if the input wasn't an integer number of
blocks, scatterwalk_done() was actually called after advancing 0 bytes.
This caused a crash ("BUG: unable to handle kernel paging request")
during '!PageSlab(page)' on architectures like arm and arm64 that define
ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE, provided that the input was
page-aligned as in that case walk->offset == 0.

Fix it by reorganizing blkcipher_walk_done() to skip the
scatterwalk_advance() and scatterwalk_done() if an error has occurred.

This bug was found by syzkaller fuzzing.

Reproducer, assuming ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE:

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

	int main()
	{
		struct sockaddr_alg addr = {
			.salg_type = "skcipher",
			.salg_name = "ecb(aes-generic)",
		};
		char buffer[4096] __attribute__((aligned(4096))) = { 0 };
		int fd;

		fd = socket(AF_ALG, SOCK_SEQPACKET, 0);
		bind(fd, (void *)&addr, sizeof(addr));
		setsockopt(fd, SOL_ALG, ALG_SET_KEY, buffer, 16);
		fd = accept(fd, NULL, NULL);
		write(fd, buffer, 15);
		read(fd, buffer, 15);
	}

Reported-by: Liu Chao <liuchao741@huawei.com>
Fixes: 5cde0af2a9 ("[CRYPTO] cipher: Added block cipher type")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-12-16 22:08:34 +00:00
Eric Biggers
217adca3b5 crypto: vmac - separate tfm and request context
commit bb29648102 upstream.

syzbot reported a crash in vmac_final() when multiple threads
concurrently use the same "vmac(aes)" transform through AF_ALG.  The bug
is pretty fundamental: the VMAC template doesn't separate per-request
state from per-tfm (per-key) state like the other hash algorithms do,
but rather stores it all in the tfm context.  That's wrong.

Also, vmac_final() incorrectly zeroes most of the state including the
derived keys and cached pseudorandom pad.  Therefore, only the first
VMAC invocation with a given key calculates the correct digest.

Fix these bugs by splitting the per-tfm state from the per-request state
and using the proper init/update/final sequencing for requests.

Reproducer for the crash:

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

    int main()
    {
            int fd;
            struct sockaddr_alg addr = {
                    .salg_type = "hash",
                    .salg_name = "vmac(aes)",
            };
            char buf[256] = { 0 };

            fd = socket(AF_ALG, SOCK_SEQPACKET, 0);
            bind(fd, (void *)&addr, sizeof(addr));
            setsockopt(fd, SOL_ALG, ALG_SET_KEY, buf, 16);
            fork();
            fd = accept(fd, NULL, NULL);
            for (;;)
                    write(fd, buf, 256);
    }

The immediate cause of the crash is that vmac_ctx_t.partial_size exceeds
VMAC_NHBYTES, causing vmac_final() to memset() a negative length.

Reported-by: syzbot+264bca3a6e8d645550d3@syzkaller.appspotmail.com
Fixes: f1939f7c56 ("crypto: vmac - New hash algorithm for intel_txt support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-12-16 22:08:08 +00:00
Daniel Borkmann
8e7eefa488 crypto: memzero_explicit - make sure to clear out sensitive data
commit 7185ad2672 upstream.

Recently, in commit 13aa93c70e71 ("random: add and use memzero_explicit()
for clearing data"), we have found that GCC may optimize some memset()
cases away when it detects a stack variable is not being used anymore
and going out of scope. This can happen, for example, in cases when we
are clearing out sensitive information such as keying material or any
e.g. intermediate results from crypto computations, etc.

With the help of Coccinelle, we can figure out and fix such occurences
in the crypto subsytem as well. Julia Lawall provided the following
Coccinelle program:

  @@
  type T;
  identifier x;
  @@

  T x;
  ... when exists
      when any
  -memset
  +memzero_explicit
     (&x,
  -0,
     ...)
  ... when != x
      when strict

  @@
  type T;
  identifier x;
  @@

  T x[...];
  ... when exists
      when any
  -memset
  +memzero_explicit
     (x,
  -0,
     ...)
  ... when != x
      when strict

Therefore, make use of the drop-in replacement memzero_explicit() for
exactly such cases instead of using memset().

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Hannes Frederic Sowa <hannes@stressinduktion.org>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-12-16 22:08:08 +00:00
Eric Biggers
e9754e4a01 crypto: vmac - require a block cipher with 128-bit block size
commit 73bf20ef3d upstream.

The VMAC template assumes the block cipher has a 128-bit block size, but
it failed to check for that.  Thus it was possible to instantiate it
using a 64-bit block size cipher, e.g. "vmac(cast5)", causing
uninitialized memory to be used.

Add the needed check when instantiating the template.

Fixes: f1939f7c56 ("crypto: vmac - New hash algorithm for intel_txt support")
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-12-16 22:08:07 +00:00
Maciej S. Szmigiero
d9399c9778 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")
Signed-off-by: James Morris <james.morris@microsoft.com>
[bwh: Backported to 3.16:
 - x509_certificate::sig is a structure, not a pointer
 - public_key_signature::pkey_algo is an enumeration type, not a string]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-11-20 18:05:27 +00:00
Eric Dumazet
8aa698134a 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>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-10-21 08:45:17 +01:00
Herbert Xu
16ba2d2e9a 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>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-10-21 08:45:06 +01:00
Eric Biggers
2f5c85c4fa 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>
[bwh: Backported to 3.16:
 - In hash_accept_parent_nokey(), update initialisation of ds to use tfm
 - Adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-06-16 22:21:52 +01:00
Eric Biggers
ac02a194f4 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>
[bwh: Backported to 3.16:
 - Drop changes to nonexistent drivers
 - There's no CRYPTO_ALG_INTERNAL flag
 - Adjust filenames]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-06-16 22:21:51 +01:00
Eric Biggers
6e118db666 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: Ben Hutchings <ben@decadent.org.uk>
2018-06-16 22:21:51 +01:00
Eric Biggers
6b3aa7a9bd 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: Ben Hutchings <ben@decadent.org.uk>
2018-06-16 22:21:51 +01:00
Stephan Mueller
cd3e607bb8 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>
[bwh: Backported to 3.16: We don't have a CRYPTO_ALG_INTENRAL flag and
 didn't blacklist it here]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-06-16 22:21:51 +01:00
Eric Biggers
1caf418c84 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: Ben Hutchings <ben@decadent.org.uk>
2018-03-03 15:52:13 +00:00
Eric Biggers
ea010ef57f 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: Ben Hutchings <ben@decadent.org.uk>
2018-03-03 15:51:49 +00:00
Eric Biggers
150fbc1221 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: Ben Hutchings <ben@decadent.org.uk>
2018-01-01 20:52:12 +00:00
Eric Biggers
9517d9d0c1 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: Ben Hutchings <ben@decadent.org.uk>
2018-01-01 20:52:11 +00:00
Herbert Xu
a5dd5f18a7 crypto: shash - Fix zero-length shash ahash digest crash
commit b61907bb42 upstream.

The shash ahash digest adaptor function may crash if given a
zero-length input together with a null SG list.  This is because
it tries to read the SG list before looking at the length.

This patch fixes it by checking the length first.

Reported-by: Stephan Müller<smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Stephan Müller <smueller@chronox.de>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2018-01-01 20:51:50 +00:00
Gilad Ben-Yossef
8b3e38ecb7 crypto: gcm - wait for crypto op not signal safe
commit f3ad587070 upstream.

crypto_gcm_setkey() was using wait_for_completion_interruptible() to
wait for completion of async crypto op but if a signal occurs it
may return before DMA ops of HW crypto provider finish, thus
corrupting the data buffer that is kfree'ed in this case.

Resolve this by using wait_for_completion() instead.

Reported-by: Eric Biggers <ebiggers3@gmail.com>
Signed-off-by: Gilad Ben-Yossef <gilad@benyossef.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2017-09-15 18:29:48 +01:00
Herbert Xu
13af702256 crypto: ahash - Fix EINPROGRESS notification callback
commit ef0579b64e upstream.

The ahash API modifies the request's callback function in order
to clean up after itself in some corner cases (unaligned final
and missing finup).

When the request is complete ahash will restore the original
callback and everything is fine.  However, when the request gets
an EBUSY on a full queue, an EINPROGRESS callback is made while
the request is still ongoing.

In this case the ahash API will incorrectly call its own callback.

This patch fixes the problem by creating a temporary request
object on the stack which is used to relay EINPROGRESS back to
the original completion function.

This patch also adds code to preserve the original flags value.

Fixes: ab6bf4e5e5 ("crypto: hash - Fix the pointer voodoo in...")
Reported-by: Sabrina Dubroca <sd@queasysnail.net>
Tested-by: Sabrina Dubroca <sd@queasysnail.net>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2017-06-05 21:17:22 +01:00
Arnd Bergmann
fa5c761a1d crypto: improve gcc optimization flags for serpent and wp512
commit 7d6e910502 upstream.

An ancient gcc bug (first reported in 2003) has apparently resurfaced
on MIPS, where kernelci.org reports an overly large stack frame in the
whirlpool hash algorithm:

crypto/wp512.c:987:1: warning: the frame size of 1112 bytes is larger than 1024 bytes [-Wframe-larger-than=]

With some testing in different configurations, I'm seeing large
variations in stack frames size up to 1500 bytes for what should have
around 300 bytes at most. I also checked the reference implementation,
which is essentially the same code but also comes with some test and
benchmarking infrastructure.

It seems that recent compiler versions on at least arm, arm64 and powerpc
have a partial fix for this problem, but enabling "-fsched-pressure", but
even with that fix they suffer from the issue to a certain degree. Some
testing on arm64 shows that the time needed to hash a given amount of
data is roughly proportional to the stack frame size here, which makes
sense given that the wp512 implementation is doing lots of loads for
table lookups, and the problem with the overly large stack is a result
of doing a lot more loads and stores for spilled registers (as seen from
inspecting the object code).

Disabling -fschedule-insns consistently fixes the problem for wp512,
in my collection of cross-compilers, the results are consistently better
or identical when comparing the stack sizes in this function, though
some architectures (notable x86) have schedule-insns disabled by
default.

The four columns are:
default: -O2
press:	 -O2 -fsched-pressure
nopress: -O2 -fschedule-insns -fno-sched-pressure
nosched: -O2 -no-schedule-insns (disables sched-pressure)

				default	press	nopress	nosched
alpha-linux-gcc-4.9.3		1136	848	1136	176
am33_2.0-linux-gcc-4.9.3	2100	2076	2100	2104
arm-linux-gnueabi-gcc-4.9.3	848	848	1048	352
cris-linux-gcc-4.9.3		272	272	272	272
frv-linux-gcc-4.9.3		1128	1000	1128	280
hppa64-linux-gcc-4.9.3		1128	336	1128	184
hppa-linux-gcc-4.9.3		644	308	644	276
i386-linux-gcc-4.9.3		352	352	352	352
m32r-linux-gcc-4.9.3		720	656	720	268
microblaze-linux-gcc-4.9.3	1108	604	1108	256
mips64-linux-gcc-4.9.3		1328	592	1328	208
mips-linux-gcc-4.9.3		1096	624	1096	240
powerpc64-linux-gcc-4.9.3	1088	432	1088	160
powerpc-linux-gcc-4.9.3		1080	584	1080	224
s390-linux-gcc-4.9.3		456	456	624	360
sh3-linux-gcc-4.9.3		292	292	292	292
sparc64-linux-gcc-4.9.3		992	240	992	208
sparc-linux-gcc-4.9.3		680	592	680	312
x86_64-linux-gcc-4.9.3		224	240	272	224
xtensa-linux-gcc-4.9.3		1152	704	1152	304

aarch64-linux-gcc-7.0.0		224	224	1104	208
arm-linux-gnueabi-gcc-7.0.1	824	824	1048	352
mips-linux-gcc-7.0.0		1120	648	1120	272
x86_64-linux-gcc-7.0.1		240	240	304	240

arm-linux-gnueabi-gcc-4.4.7	840			392
arm-linux-gnueabi-gcc-4.5.4	784	728	784	320
arm-linux-gnueabi-gcc-4.6.4	736	728	736	304
arm-linux-gnueabi-gcc-4.7.4	944	784	944	352
arm-linux-gnueabi-gcc-4.8.5	464	464	760	352
arm-linux-gnueabi-gcc-4.9.3	848	848	1048	352
arm-linux-gnueabi-gcc-5.3.1	824	824	1064	336
arm-linux-gnueabi-gcc-6.1.1	808	808	1056	344
arm-linux-gnueabi-gcc-7.0.1	824	824	1048	352

Trying the same test for serpent-generic, the picture is a bit different,
and while -fno-schedule-insns is generally better here than the default,
-fsched-pressure wins overall, so I picked that instead.

				default	press	nopress	nosched
alpha-linux-gcc-4.9.3		1392	864	1392	960
am33_2.0-linux-gcc-4.9.3	536	524	536	528
arm-linux-gnueabi-gcc-4.9.3	552	552	776	536
cris-linux-gcc-4.9.3		528	528	528	528
frv-linux-gcc-4.9.3		536	400	536	504
hppa64-linux-gcc-4.9.3		524	208	524	480
hppa-linux-gcc-4.9.3		768	472	768	508
i386-linux-gcc-4.9.3		564	564	564	564
m32r-linux-gcc-4.9.3		712	576	712	532
microblaze-linux-gcc-4.9.3	724	392	724	512
mips64-linux-gcc-4.9.3		720	384	720	496
mips-linux-gcc-4.9.3		728	384	728	496
powerpc64-linux-gcc-4.9.3	704	304	704	480
powerpc-linux-gcc-4.9.3		704	296	704	480
s390-linux-gcc-4.9.3		560	560	592	536
sh3-linux-gcc-4.9.3		540	540	540	540
sparc64-linux-gcc-4.9.3		544	352	544	496
sparc-linux-gcc-4.9.3		544	344	544	496
x86_64-linux-gcc-4.9.3		528	536	576	528
xtensa-linux-gcc-4.9.3		752	544	752	544

aarch64-linux-gcc-7.0.0		432	432	656	480
arm-linux-gnueabi-gcc-7.0.1	616	616	808	536
mips-linux-gcc-7.0.0		720	464	720	488
x86_64-linux-gcc-7.0.1		536	528	600	536

arm-linux-gnueabi-gcc-4.4.7	592			440
arm-linux-gnueabi-gcc-4.5.4	776	448	776	544
arm-linux-gnueabi-gcc-4.6.4	776	448	776	544
arm-linux-gnueabi-gcc-4.7.4	768	448	768	544
arm-linux-gnueabi-gcc-4.8.5	488	488	776	544
arm-linux-gnueabi-gcc-4.9.3	552	552	776	536
arm-linux-gnueabi-gcc-5.3.1	552	552	776	536
arm-linux-gnueabi-gcc-6.1.1	560	560	776	536
arm-linux-gnueabi-gcc-7.0.1	616	616	808	536

I did not do any runtime tests with serpent, so it is possible that stack
frame size does not directly correlate with runtime performance here and
it actually makes things worse, but it's more likely to help here, and
the reduced stack frame size is probably enough reason to apply the patch,
especially given that the crypto code is often used in deep call chains.

Link: https://kernelci.org/build/id/58797d7559b5149efdf6c3a9/logs/
Link: http://www.larc.usp.br/~pbarreto/WhirlpoolPage.html
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=11488
Link: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=79149
Cc: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2017-04-04 22:21:55 +01:00
Salvatore Benedetto
3ae51b03e5 crypto: api - Clear CRYPTO_ALG_DEAD bit before registering an alg
commit d6040764ad upstream.

Make sure CRYPTO_ALG_DEAD bit is cleared before proceeding with
the algorithm registration. This fixes qat-dh registration when
driver is restarted

Signed-off-by: Salvatore Benedetto <salvatore.benedetto@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2017-03-16 02:27:04 +00:00
Justin Maggard
c3fa800fe9 async_pq_val: fix DMA memory leak
commit c84750906b upstream.

Add missing dmaengine_unmap_put(), so we don't OOM during RAID6 sync.

Fixes: 1786b943da ("async_pq_val: convert to dmaengine_unmap_data")
Signed-off-by: Justin Maggard <jmaggard@netgear.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2017-02-23 03:54:09 +00:00
Ondrej Mosnáček
615e796a88 crypto: gcm - Fix IV buffer size in crypto_gcm_setkey
commit 50d2e6dc1f upstream.

The cipher block size for GCM is 16 bytes, and thus the CTR transform
used in crypto_gcm_setkey() will also expect a 16-byte IV. However,
the code currently reserves only 8 bytes for the IV, causing
an out-of-bounds access in the CTR transform. This patch fixes
the issue by setting the size of the IV buffer to 16 bytes.

Fixes: 84c9115230 ("[CRYPTO] gcm: Add support for async ciphers")
Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2017-02-23 03:54:07 +00:00
Herbert Xu
c5ffd60857 crypto: skcipher - Fix blkcipher walk OOM crash
commit acdb04d0b3 upstream.

When we need to allocate a temporary blkcipher_walk_next and it
fails, the code is supposed to take the slow path of processing
the data block by block.  However, due to an unrelated change
we instead end up dereferencing the NULL pointer.

This patch fixes it by moving the unrelated bsize setting out
of the way so that we enter the slow path as inteded.

Fixes: 7607bd8ff0 ("[CRYPTO] blkcipher: Added blkcipher_walk_virt_block")
Reported-by: xiakaixu <xiakaixu@huawei.com>
Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-11-20 01:17:26 +00:00
Ard Biesheuvel
151b56d3a1 crypto: cryptd - initialize child shash_desc on import
commit 0bd2223594 upstream.

When calling .import() on a cryptd ahash_request, the structure members
that describe the child transform in the shash_desc need to be initialized
like they are when calling .init()

Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-11-20 01:17:24 +00:00
Herbert Xu
5505be8414 crypto: scatterwalk - Fix test in scatterwalk_done
commit 5f070e81be upstream.

When there is more data to be processed, the current test in
scatterwalk_done may prevent us from calling pagedone even when
we should.

In particular, if we're on an SG entry spanning multiple pages
where the last page is not a full page, we will incorrectly skip
calling pagedone on the second last page.

This patch fixes this by adding a separate test for whether we've
reached the end of a page.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-11-20 01:16:53 +00:00
Herbert Xu
2da0ef6079 crypto: gcm - Filter out async ghash if necessary
commit b30bdfa864 upstream.

As it is if you ask for a sync gcm you may actually end up with
an async one because it does not filter out async implementations
of ghash.

This patch fixes this by adding the necessary filter when looking
for ghash.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-11-20 01:16:41 +00:00
Arnd Bergmann
99e2057a42 crypto: public_key: select CRYPTO_AKCIPHER
commit bad6a185b4 upstream.

In some rare randconfig builds, we can end up with
ASYMMETRIC_PUBLIC_KEY_SUBTYPE enabled but CRYPTO_AKCIPHER disabled,
which fails to link because of the reference to crypto_alloc_akcipher:

crypto/built-in.o: In function `public_key_verify_signature':
:(.text+0x110e4): undefined reference to `crypto_alloc_akcipher'

This adds a Kconfig 'select' statement to ensure the dependency
is always there.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-08-22 22:38:02 +01:00
Herbert Xu
b986834b2c crypto: hash - Fix page length clamping in hash walk
commit 13f4bb78cf upstream.

The crypto hash walk code is broken when supplied with an offset
greater than or equal to PAGE_SIZE.  This patch fixes it by adjusting
walk->pg and walk->offset when this happens.

Reported-by: Steffen Klassert <steffen.klassert@secunet.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
2016-06-15 21:29:30 +01:00
Herbert Xu
e5393d8034 crypto: gcm - Fix rfc4543 decryption crash
This bug has already bee fixed upstream since 4.2.  However, it
was fixed during the AEAD conversion so no fix was backported to
the older kernels.

[bwh: The upstream commit was adcbc688fe ("crypto: gcm - Convert to
new AEAD interface")]

When we do an RFC 4543 decryption, we will end up writing the
ICV beyond the end of the dst buffer.  This should lead to a
crash but for some reason it was never noticed.

This patch fixes it by only writing back the ICV for encryption.

Fixes: d733ac90f9 ("crypto: gcm - fix rfc4543 to handle async...")
Reported-by: Patrick Meyer <patrick.meyer@vasgard.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-05-01 00:06:15 +02:00
Ben Hutchings
63ce06ed72 crypto: {blk,giv}cipher: Set has_setkey
Commit a1383cd86a ("crypto: skcipher - Add crypto_skcipher_has_setkey")
was incorrectly backported to the 3.2.y and 3.16.y stable branches.
We need to set ablkcipher_tfm::has_setkey in the
crypto_init_blkcipher_ops_async() and crypto_init_givcipher_ops()
functions as well as crypto_init_ablkcipher_ops().

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2016-03-08 12:15:18 +00:00
Mathias Krause
113241155f crypto: user - lock crypto_alg_list on alg dump
commit 63e41ebc66 upstream.

We miss to take the crypto_alg_sem semaphore when traversing the
crypto_alg_list for CRYPTO_MSG_GETALG dumps. This allows a race with
crypto_unregister_alg() removing algorithms from the list while we're
still traversing it, thereby leading to a use-after-free as show below:

[ 3482.071639] general protection fault: 0000 [#1] SMP
[ 3482.075639] Modules linked in: aes_x86_64 glue_helper lrw ablk_helper cryptd gf128mul ipv6 pcspkr serio_raw virtio_net microcode virtio_pci virtio_ring virtio sr_mod cdrom [last unloaded: aesni_intel]
[ 3482.075639] CPU: 1 PID: 11065 Comm: crconf Not tainted 4.3.4-grsec+ #126
[ 3482.075639] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.7.5-20140531_083030-gandalf 04/01/2014
[ 3482.075639] task: ffff88001cd41a40 ti: ffff88001cd422c8 task.ti: ffff88001cd422c8
[ 3482.075639] RIP: 0010:[<ffffffff93722bd3>]  [<ffffffff93722bd3>] strncpy+0x13/0x30
[ 3482.075639] RSP: 0018:ffff88001f713b60  EFLAGS: 00010202
[ 3482.075639] RAX: ffff88001f6c4430 RBX: ffff88001f6c43a0 RCX: ffff88001f6c4430
[ 3482.075639] RDX: 0000000000000040 RSI: fefefefefefeff16 RDI: ffff88001f6c4430
[ 3482.075639] RBP: ffff88001f713b60 R08: ffff88001f6c4470 R09: ffff88001f6c4480
[ 3482.075639] R10: 0000000000000002 R11: 0000000000000246 R12: ffff88001ce2aa28
[ 3482.075639] R13: ffff880000093700 R14: ffff88001f5e4bf8 R15: 0000000000003b20
[ 3482.075639] FS:  0000033826fa2700(0000) GS:ffff88001e900000(0000) knlGS:0000000000000000
[ 3482.075639] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[ 3482.075639] CR2: ffffffffff600400 CR3: 00000000139ec000 CR4: 00000000001606f0
[ 3482.075639] Stack:
[ 3482.075639]  ffff88001f713bd8 ffffffff936ccd00 ffff88001e5c4200 ffff880000093700
[ 3482.075639]  ffff88001f713bd0 ffffffff938ef4bf 0000000000000000 0000000000003b20
[ 3482.075639]  ffff88001f5e4bf8 ffff88001f5e4848 0000000000000000 0000000000003b20
[ 3482.075639] Call Trace:
[ 3482.075639]  [<ffffffff936ccd00>] crypto_report_alg+0xc0/0x3e0
[ 3482.075639]  [<ffffffff938ef4bf>] ? __alloc_skb+0x16f/0x300
[ 3482.075639]  [<ffffffff936cd08a>] crypto_dump_report+0x6a/0x90
[ 3482.075639]  [<ffffffff93935707>] netlink_dump+0x147/0x2e0
[ 3482.075639]  [<ffffffff93935f99>] __netlink_dump_start+0x159/0x190
[ 3482.075639]  [<ffffffff936ccb13>] crypto_user_rcv_msg+0xc3/0x130
[ 3482.075639]  [<ffffffff936cd020>] ? crypto_report_alg+0x3e0/0x3e0
[ 3482.075639]  [<ffffffff936cc4b0>] ? alg_test_crc32c+0x120/0x120
[ 3482.075639]  [<ffffffff93933145>] ? __netlink_lookup+0xd5/0x120
[ 3482.075639]  [<ffffffff936cca50>] ? crypto_add_alg+0x1d0/0x1d0
[ 3482.075639]  [<ffffffff93938141>] netlink_rcv_skb+0xe1/0x130
[ 3482.075639]  [<ffffffff936cc4f8>] crypto_netlink_rcv+0x28/0x40
[ 3482.075639]  [<ffffffff939375a8>] netlink_unicast+0x108/0x180
[ 3482.075639]  [<ffffffff93937c21>] netlink_sendmsg+0x541/0x770
[ 3482.075639]  [<ffffffff938e31e1>] sock_sendmsg+0x21/0x40
[ 3482.075639]  [<ffffffff938e4763>] SyS_sendto+0xf3/0x130
[ 3482.075639]  [<ffffffff93444203>] ? bad_area_nosemaphore+0x13/0x20
[ 3482.075639]  [<ffffffff93444470>] ? __do_page_fault+0x80/0x3a0
[ 3482.075639]  [<ffffffff939d80cb>] entry_SYSCALL_64_fastpath+0x12/0x6e
[ 3482.075639] Code: 88 4a ff 75 ed 5d 48 0f ba 2c 24 3f c3 66 66 2e 0f 1f 84 00 00 00 00 00 55 48 85 d2 48 89 f8 48 89 f9 4c 8d 04 17 48 89 e5 74 15 <0f> b6 16 80 fa 01 88 11 48 83 de ff 48 83 c1 01 4c 39 c1 75 eb
[ 3482.075639] RIP  [<ffffffff93722bd3>] strncpy+0x13/0x30

To trigger the race run the following loops simultaneously for a while:
  $ while : ; do modprobe aesni-intel; rmmod aesni-intel; done
  $ while : ; do crconf show all > /dev/null; done

Fix the race by taking the crypto_alg_sem read lock, thereby preventing
crypto_unregister_alg() from modifying the algorithm list during the
dump.

This bug has been detected by the PaX memory sanitize feature.

Signed-off-by: Mathias Krause <minipli@googlemail.com>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: PaX Team <pageexec@freemail.hu>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2016-02-25 10:34:46 +00:00
Wang, Rui Y
f5892ce337 crypto: algif_hash - wait for crypto_ahash_init() to complete
commit fe09786178 upstream.

hash_sendmsg/sendpage() need to wait for the completion
of crypto_ahash_init() otherwise it can cause panic.

Signed-off-by: Rui Wang <rui.y.wang@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2016-02-25 00:18:38 +00:00
Herbert Xu
7c684091e6 crypto: shash - Fix has_key setting
commit 00420a65fa upstream.

The has_key logic is wrong for shash algorithms as they always
have a setkey function.  So we should instead be testing against
shash_no_setkey.

Fixes: a5596d6332 ("crypto: hash - Add crypto_ahash_has_setkey")
Reported-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Stephan Mueller <smueller@chronox.de>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2016-02-25 00:18:37 +00:00
Herbert Xu
7dffe6c5be crypto: algif_skcipher - Fix race condition in skcipher_check_key
commit 1822793a52 upstream.

We need to lock the child socket in skcipher_check_key as otherwise
two simultaneous calls can cause the parent socket to be freed.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2016-02-24 14:41:18 +00:00
Herbert Xu
f47ff3820b crypto: algif_hash - Fix race condition in hash_check_key
commit ad46d7e332 upstream.

We need to lock the child socket in hash_check_key as otherwise
two simultaneous calls can cause the parent socket to be freed.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2016-02-24 14:40:37 +00:00
Herbert Xu
2643fc0d9d crypto: algif_skcipher - Remove custom release parent function
commit d7b65aee1e upstream.

This patch removes the custom release parent function as the
generic af_alg_release_parent now works for nokey sockets too.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2016-02-24 14:39:49 +00:00
Herbert Xu
82822540e7 crypto: algif_hash - Remove custom release parent function
commit f1d84af183 upstream.

This patch removes the custom release parent function as the
generic af_alg_release_parent now works for nokey sockets too.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2016-02-24 14:35:03 +00:00
Herbert Xu
c8f7691fa1 crypto: algif_skcipher - Add key check exception for cipher_null
commit 6e8d8ecf43 upstream.

This patch adds an exception to the key check so that cipher_null
users may continue to use algif_skcipher without setting a key.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.2: use crypto_ablkcipher_has_setkey()]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2016-02-24 14:34:07 +00:00
Herbert Xu
05b93b57b6 crypto: skcipher - Add crypto_skcipher_has_setkey
commit a1383cd86a upstream.

This patch adds a way for skcipher users to determine whether a key
is required by a transform.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
[bwh: Backported to 3.2: add to ablkcipher API instead]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
2016-02-24 14:31:26 +00:00