Commit Graph

9 Commits

Author SHA1 Message Date
Greg Kroah-Hartman 1f2493fcd8 Revert: "crypto: af_alg - Disallow bind/setkey/... after accept(2)"
This reverts commit 5a707f0972 which is
commit c840ac6af3f8713a71b4d2363419145760bd6044 upstream.

It's been widely reported that this patch breaks existing userspace
applications when backported to the stable kernel releases.  As no fix
seems to be forthcoming, just revert it to let systems work again.

Reported-by: "J. Paul Reed" <preed@sigkill.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-03-16 08:41:37 -07:00
Herbert Xu f77597b2ef crypto: af_alg - Fix socket double-free when accept fails
commit a383292c86663bbc31ac62cc0c04fc77504636a6 upstream.

When we fail an accept(2) call we will end up freeing the socket
twice, once due to the direct sk_free call and once again through
newsock.

This patch fixes this by removing the sk_free call.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-19 14:22:41 -08:00
Herbert Xu 5a707f0972 crypto: af_alg - Disallow bind/setkey/... after accept(2)
commit c840ac6af3f8713a71b4d2363419145760bd6044 upstream.

Each af_alg parent socket obtained by socket(2) corresponds to a
tfm object once bind(2) has succeeded.  An accept(2) call on that
parent socket creates a context which then uses the tfm object.

Therefore as long as any child sockets created by accept(2) exist
the parent socket must not be modified or freed.

This patch guarantees this by using locks and a reference count
on the parent socket.  Any attempt to modify the parent socket will
fail with EBUSY.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2016-02-19 14:22:41 -08:00
Rabin Vincent 3d53f1f716 crypto: af_alg - fix backlog handling
commit 7e77bdebff5cb1e9876c561f69710b9ab8fa1f7e upstream.

If a request is backlogged, it's complete() handler will get called
twice: once with -EINPROGRESS, and once with the final error code.

af_alg's complete handler, unlike other users, does not handle the
-EINPROGRESS but instead always completes the completion that recvmsg()
is waiting on.  This can lead to a return to user space while the
request is still pending in the driver.  If userspace closes the sockets
before the requests are handled by the driver, this will lead to
use-after-frees (and potential crashes) in the kernel due to the tfm
having been freed.

The crashes can be easily reproduced (for example) by reducing the max
queue length in cryptod.c and running the following (from
http://www.chronox.de/libkcapi.html) on AES-NI capable hardware:

 $ while true; do kcapi -x 1 -e -c '__ecb-aes-aesni' \
    -k 00000000000000000000000000000000 \
    -p 00000000000000000000000000000000 >/dev/null & done

Signed-off-by: Rabin Vincent <rabin.vincent@axis.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2015-01-08 09:58:17 -08:00
Milan Broz 4a6d0c804f crypto: af_alg - properly label AF_ALG socket
commit 4c63f83c2c2e16a13ce274ee678e28246bd33645 upstream.

Th AF_ALG socket was missing a security label (e.g. SELinux)
which means that socket was in "unlabeled" state.

This was recently demonstrated in the cryptsetup package
(cryptsetup v1.6.5 and later.)
See https://bugzilla.redhat.com/show_bug.cgi?id=1115120

This patch clones the sock's label from the parent sock
and resolves the issue (similar to AF_BLUETOOTH protocol family).

Signed-off-by: Milan Broz <gmazyland@gmail.com>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2014-08-07 14:30:25 -07:00
Arun Sharma 60063497a9 atomic: use <linux/atomic.h>
This allows us to move duplicated code in <asm/atomic.h>
(atomic_inc_not_zero() for now) to <linux/atomic.h>

Signed-off-by: Arun Sharma <asharma@fb.com>
Reviewed-by: Eric Dumazet <eric.dumazet@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: David Miller <davem@davemloft.net>
Cc: Eric Dumazet <eric.dumazet@gmail.com>
Acked-by: Mike Frysinger <vapier@gentoo.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-07-26 16:49:47 -07:00
Randy Dunlap 0686952458 crypto: af_alg - fix af_alg memory_allocated data type
Change data type to fix warning:

crypto/af_alg.c:35: warning: initialization from incompatible pointer type

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-12-21 22:22:40 +11:00
Miloslav Trmač 507cad355f crypto: af_alg - Make sure sk_security is initialized on accept()ed sockets
Signed-off-by: Miloslav Trmač <mitr@redhat.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2010-12-08 14:36:19 +08:00
Herbert Xu 03c8efc1ff crypto: af_alg - User-space interface for Crypto API
This patch creates the backbone of the user-space interface for
the Crypto API, through a new socket family AF_ALG.

Each session corresponds to one or more connections obtained from
that socket.  The number depends on the number of inputs/outputs
of that particular type of operation.  For most types there will
be a s ingle connection/file descriptor that is used for both input
and output.  AEAD is one of the few that require two inputs.

Each algorithm type will provide its own implementation that plugs
into af_alg.  They're keyed using a string such as "skcipher" or
"hash".

IOW this patch only contains the boring bits that is required
to hold everything together.

Thakns to Miloslav Trmac for reviewing this and contributing
fixes and improvements.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Acked-by: David S. Miller <davem@davemloft.net>
Tested-by: Martin Willi <martin@strongswan.org>
2010-11-19 17:47:57 +08:00