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")
Cc: <stable@vger.kernel.org> # v2.6.25+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Commit 5d26a105b5 ("crypto: prefix module autoloading with "crypto-"")
changed the automatic module loading when requesting crypto algorithms
to prefix all module requests with "crypto-". This requires all crypto
modules to have a crypto specific module alias even if their file name
would otherwise match the requested crypto algorithm.
Even though commit 5d26a105b5 added those aliases for a vast amount of
modules, it was missing a few. Add the required MODULE_ALIAS_CRYPTO
annotations to those files to make them get loaded automatically, again.
This fixes, e.g., requesting 'ecb(blowfish-generic)', which used to work
with kernels v3.18 and below.
Also change MODULE_ALIAS() lines to MODULE_ALIAS_CRYPTO(). The former
won't work for crypto modules any more.
Fixes: 5d26a105b5 ("crypto: prefix module autoloading with "crypto-"")
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Mathias Krause <minipli@googlemail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This prefixes all crypto module loading with "crypto-" so we never run
the risk of exposing module auto-loading to userspace via a crypto API,
as demonstrated by Mathias Krause:
https://lkml.org/lkml/2013/3/4/70
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Initialization of cra_list is currently mixed, most ciphers initialize this
field and most shashes do not. Initialization however is not needed at all
since cra_list is initialized/overwritten in __crypto_register_alg() with
list_add(). Therefore perform cleanup to remove all unneeded initializations
of this field in 'crypto/'.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@mbnet.fi>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
ROTATE -> rol32
XOR was always used with the same destination, use ^=
PLUS/PLUSONE use ++ or +=
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
On Thu, Mar 27, 2008 at 03:40:36PM +0100, Bodo Eggert wrote:
> Kamalesh Babulal <kamalesh@linux.vnet.ibm.com> wrote:
>
> > This patch cleanups the crypto code, replaces the init() and fini()
> > with the <algorithm name>_init/_fini
>
> This part ist OK.
>
> > or init/fini_<algorithm name> (if the
> > <algorithm name>_init/_fini exist)
>
> Having init_foo and foo_init won't be a good thing, will it? I'd start
> confusing them.
>
> What about foo_modinit instead?
Thanks for the suggestion, the init() is replaced with
<algorithm name>_mod_init ()
and fini () is replaced with <algorithm name>_mod_fini.
Signed-off-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This patch fixes the multi-page processing bug that affects large test
vectors (the same bug that previously affected ctr.c).
There is an optimization for the case walk.nbytes == nbytes. Also we
now use crypto_xor() instead of adhoc XOR routines.
Signed-off-by: Tan Swee Heng <thesweeheng@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Eric Biggers