kernel/include/crypto/vmac.h, branch linux-4.14.yHosts the 0x221E linux distro kernel.https://universe.0xinfinity.dev/distro/kernel/atom?h=linux-4.14.y2018-08-17T19:01:10Zcrypto: vmac - separate tfm and request context2018-08-17T19:01:10ZEric Biggersebiggers@google.com2018-06-18T17:22:38Zurn:sha1:e7aefb13e61c52e025c510bc6372dc08edbdf27b
commit bb29648102335586e9a66289a1d98a0cb392b6e5 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: f1939f7c5645 ("crypto: vmac - New hash algorithm for intel_txt support")
Cc: <stable@vger.kernel.org> # v2.6.32+
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
crypto: vmac - Make VMAC work when blocks aren't aligned2012-10-15T14:33:20ZSalman Qazisqazi@google.com2012-10-05T21:24:14Zurn:sha1:ba1ee070909fae01248b8117da1706f3cf2bfd1b
VMAC implementation, as it is, does not work with blocks that
are not multiples of 128-bytes. Furthermore, this is a problem
when using the implementation on scatterlists, even
when the complete plain text is 128-byte multiple, as the pieces
that get passed to vmac_update can be pretty much any size.
I also added test cases for unaligned blocks.
Signed-off-by: Salman Qazi <sqazi@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
crypto: vmac - New hash algorithm for intel_txt support2009-09-02T10:05:22ZShane Wangshane.wang@intel.com2009-09-02T10:05:22Zurn:sha1:f1939f7c56456d22a559d2c75156e91912a2e97e
This patch adds VMAC (a fast MAC) support into crypto framework.
Signed-off-by: Shane Wang <shane.wang@intel.com>
Signed-off-by: Joseph Cihula <joseph.cihula@intel.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>