crypto: sun8i-ce - Fix use after free in unprepare

sun8i_ce_cipher_unprepare should be called before
crypto_finalize_skcipher_request, because client callbacks may
immediately free memory, that isn't needed anymore. But it will be
used by unprepare after free. Before removing prepare/unprepare
callbacks it was handled by crypto engine in crypto_finalize_request.

Usually that results in a pointer dereference problem during a in
crypto selftest.
Unable to handle kernel NULL pointer dereference at
virtual address 0000000000000030
Mem abort info:
ESR = 0x0000000096000004
EC = 0x25: DABT (current EL), IL = 32 bits
SET = 0, FnV = 0
EA = 0, S1PTW = 0
FSC = 0x04: level 0 translation fault
Data abort info:
ISV = 0, ISS = 0x00000004, ISS2 = 0x00000000
CM = 0, WnR = 0, TnD = 0, TagAccess = 0
GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
user pgtable: 4k pages, 48-bit VAs, pgdp=000000004716d000
[0000000000000030] pgd=0000000000000000, p4d=0000000000000000
Internal error: Oops: 0000000096000004 [#1] SMP

This problem is detected by KASAN as well.
==================================================================
BUG: KASAN: slab-use-after-free in sun8i_ce_cipher_do_one+0x6e8/0xf80 [sun8i_ce]
Read of size 8 at addr ffff00000dcdc040 by task 1c15000.crypto-/373

Hardware name: Pine64 PinePhone (1.2) (DT)
Call trace:
dump_backtrace+0x9c/0x128
show_stack+0x20/0x38
dump_stack_lvl+0x48/0x60
print_report+0xf8/0x5d8
kasan_report+0x90/0xd0
__asan_load8+0x9c/0xc0
sun8i_ce_cipher_do_one+0x6e8/0xf80 [sun8i_ce]
crypto_pump_work+0x354/0x620 [crypto_engine]
kthread_worker_fn+0x244/0x498
kthread+0x168/0x178
ret_from_fork+0x10/0x20

Allocated by task 379:
kasan_save_stack+0x3c/0x68
kasan_set_track+0x2c/0x40
kasan_save_alloc_info+0x24/0x38
__kasan_kmalloc+0xd4/0xd8
__kmalloc+0x74/0x1d0
alg_test_skcipher+0x90/0x1f0
alg_test+0x24c/0x830
cryptomgr_test+0x38/0x60
kthread+0x168/0x178
ret_from_fork+0x10/0x20

Freed by task 379:
kasan_save_stack+0x3c/0x68
kasan_set_track+0x2c/0x40
kasan_save_free_info+0x38/0x60
__kasan_slab_free+0x100/0x170
slab_free_freelist_hook+0xd4/0x1e8
__kmem_cache_free+0x15c/0x290
kfree+0x74/0x100
kfree_sensitive+0x80/0xb0
alg_test_skcipher+0x12c/0x1f0
alg_test+0x24c/0x830
cryptomgr_test+0x38/0x60
kthread+0x168/0x178
ret_from_fork+0x10/0x20

The buggy address belongs to the object at ffff00000dcdc000
which belongs to the cache kmalloc-256 of size 256
The buggy address is located 64 bytes inside of
freed 256-byte region [ffff00000dcdc000, ffff00000dcdc100)

Signed-off-by: Andrey Skvortsov <andrej.skvortzov@gmail.com>
Fixes: 4136212ab18e ("crypto: sun8i-ce - Remove prepare/unprepare request")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - Use helper to set reqsize

The value of reqsize must only be changed through the helper.

Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - Use new crypto_engine_op interface

Use the new crypto_engine_op interface where the callback is stored
in the algorithm object.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - Remove prepare/unprepare request

The callbacks for prepare and unprepare request in crypto_engine
is superfluous. They can be done directly from do_one_request.

Move the code into do_one_request and remove the unused callbacks.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: update some Arm documentation references

The Arm documentation has moved to Documentation/arch/arm; update a
set of references under crypto/allwinner to match.

Cc: Corentin Labbe <clabbe.montjoie@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Samuel Holland <samuel@sholland.org>
Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Revert "crypto: allwinner - Fix dma_map_sg error check"

This reverts commit 2b02187bdb0bb75000850bd0309e70eb8664159e.

The original code was correct and arguably more robust than the
patched version.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: allwinner - Fix dma_map_sg error check

dma_map_sg return 0 on error.

Cc: Corentin Labbe <clabbe.montjoie@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Chen-Yu Tsai <wens@csie.org>
Cc: Jernej Skrabec <jernej.skrabec@gmail.com>
Cc: Samuel Holland <samuel@sholland.org>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Minghao Chi <chi.minghao@zte.com.cn>
Cc: Peng Wu <wupeng58@huawei.com>
Cc: Alexey Khoroshilov <khoroshilov@ispras.ru>
Cc: linux-crypto@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-sunxi@lists.linux.dev
Cc: linux-kernel@vger.kernel.org

Signed-off-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - do not fallback if cryptlen is less than sg length

The sg length could be more than remaining data on it.
So check the length requirement against the minimum between those two
values.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - rework debugging

The "Fallback for xxx" message is annoying, remove it and store the
information in the debugfs.
Let's add more precise fallback stats and display it better.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - use sg_nents_for_len

When testing with some large SG list, the sun8i-ce drivers always
fallback even if it can handle it.
So use sg_nents_for_len() which permits to see less SGs than needed.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - do not allocate memory when handling requests

Instead of allocate memory on each requests, it is easier to
pre-allocate buffer for IV.
This made error path easier.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - Fix minor style issue

This patch remove a double blank line.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - call finalize with bh disabled

Doing ipsec produces a spinlock recursion warning.
This is due to not disabling BH during crypto completion function.

Fixes: 06f751b61329 ("crypto: allwinner - Add sun8i-ce Crypto Engine")
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: allwinner - Fix the parameter of dma_unmap_sg()

For function dma_unmap_sg(), the <nents> parameter should be number of
elements in the scatterlist prior to the mapping, not after the mapping.
So fix this usage.

Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Acked-by: Corentin LABBE <clabbe.montjoie@gmail.com>
Tested-by: Corentin LABBE <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - rename has_t_dlen_in_bytes to cipher_t_dlen_in_bytes

Hash algorithms will need also a spetial t_dlen handling, but since the
meaning will be different, rename the current flag to specify it apply
only on ciphers algorithms.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - split into prepare/run/unprepare

This patch split the do_one_request into three.
Prepare will handle all DMA mapping and initialisation of the task
structure.
Unprepare will clean all DMA mapping.
And the do_one_request will be limited to just executing the task.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - move iv data to request context

Instead of storing IV data in the channel context, store them in the
request context.
Storing them in the channel structure was conceptualy wrong since they
are per request related.

Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - use kfree_sensitive()

Use kfree_sensitive() instead of open-coding it.

Signed-off-by: Denis Efremov <efremov@linux.com>
Acked-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

mm, treewide: rename kzfree() to kfree_sensitive()

As said by Linus:

A symmetric naming is only helpful if it implies symmetries in use.
Otherwise it's actively misleading.

In "kzalloc()", the z is meaningful and an important part of what the
caller wants.

In "kzfree()", the z is actively detrimental, because maybe in the
future we really _might_ want to use that "memfill(0xdeadbeef)" or
something. The "zero" part of the interface isn't even _relevant_.

The main reason that kzfree() exists is to clear sensitive information
that should not be leaked to other future users of the same memory
objects.

Rename kzfree() to kfree_sensitive() to follow the example of the recently
added kvfree_sensitive() and make the intention of the API more explicit.
In addition, memzero_explicit() is used to clear the memory to make sure
that it won't get optimized away by the compiler.

The renaming is done by using the command sequence:

git grep -w --name-only kzfree |\
xargs sed -i 's/kzfree/kfree_sensitive/'

followed by some editing of the kfree_sensitive() kerneldoc and adding
a kzfree backward compatibility macro in slab.h.

[akpm@linux-foundation.org: fs/crypto/inline_crypt.c needs linux/slab.h]
[akpm@linux-foundation.org: fix fs/crypto/inline_crypt.c some more]

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: David Howells <dhowells@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: James Morris <jmorris@namei.org>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Joe Perches <joe@perches.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: "Jason A . Donenfeld" <Jason@zx2c4.com>
Link: http://lkml.kernel.org/r/20200616154311.12314-3-longman@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

crypto: sun8i-ce - permit asynchronous skcipher as fallback

Even though the sun8i-ce driver implements asynchronous versions of
ecb(aes) and cbc(aes), the fallbacks it allocates are required to be
synchronous. Given that SIMD based software implementations are usually
asynchronous as well, even though they rarely complete asynchronously
(this typically only happens in cases where the request was made from
softirq context, while SIMD was already in use in the task context that
it interrupted), these implementations are disregarded, and either the
generic C version or another table based version implemented in assembler
is selected instead.

Since falling back to synchronous AES is not only a performance issue, but
potentially a security issue as well (due to the fact that table based AES
is not time invariant), let's fix this, by allocating an ordinary skcipher
as the fallback, and invoke it with the completion routine that was given
to the outer request.

Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Acked-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Tested-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - Fix runtime PM imbalance in sun8i_ce_cipher_init

pm_runtime_get_sync() increments the runtime PM usage counter even
the call returns an error code. Thus a corresponding decrement is
needed on the error handling path to keep the counter balanced.

Fix this by adding the missed function call.

Signed-off-by: Dinghao Liu <dinghao.liu@zju.edu.cn>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

docs: fix broken references for ReST files that moved around

Some broken references happened due to shifting files around
and ReST renames. Those can't be auto-fixed by the script,
so let's fix them manually.

Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Acked-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Link: https://lore.kernel.org/r/64773a12b4410aaf3e3be89e3ec7e34de2484eea.1586881715.git.mchehab+huawei@kernel.org
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

crypto: sun8i-ce - remove dead code

Some code were left in the final driver but without any use.

Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: remove CRYPTO_TFM_RES_BAD_KEY_LEN

The CRYPTO_TFM_RES_BAD_KEY_LEN flag was apparently meant as a way to
make the ->setkey() functions provide more information about errors.

However, no one actually checks for this flag, which makes it pointless.

Also, many algorithms fail to set this flag when given a bad length key.
Reviewing just the generic implementations, this is the case for
aes-fixed-time, cbcmac, echainiv, nhpoly1305, pcrypt, rfc3686, rfc4309,
rfc7539, rfc7539esp, salsa20, seqiv, and xcbc. But there are probably
many more in arch/*/crypto/ and drivers/crypto/.

Some algorithms can even set this flag when the key is the correct
length. For example, authenc and authencesn set it when the key payload
is malformed in any way (not just a bad length), the atmel-sha and ccree
drivers can set it if a memory allocation fails, and the chelsio driver
sets it for bad auth tag lengths, not just bad key lengths.

So even if someone actually wanted to start checking this flag (which
seems unlikely, since it's been unused for a long time), there would be
a lot of work needed to get it working correctly. But it would probably
be much better to go back to the drawing board and just define different
return values, like -EINVAL if the key is invalid for the algorithm vs.
-EKEYREJECTED if the key was rejected by a policy like "no weak keys".
That would be much simpler, less error-prone, and easier to test.

So just remove this flag.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Reviewed-by: Horia Geantă <horia.geanta@nxp.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - enable working on big endian

On big endian kernel, the sun8i-ce crypto driver does not works.
This patch do the necessary modification to permit it to work on BE
kernel (setting descriptor entries as __le32 and adding some cpu_to_le32)

Fixes: 06f751b61329 ("crypto: allwinner - Add sun8i-ce Crypto Engine")
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: sun8i-ce - Fix memdup.cocci warnings

Use kmemdup rather than duplicating its implementation

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

crypto: allwinner - Add sun8i-ce Crypto Engine

The Crypto Engine is an hardware cryptographic offloader present
on all recent Allwinner SoCs H2+, H3, R40, A64, H5, H6

This driver supports AES cipher in CBC/ECB mode.

Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Corentin Labbe <clabbe.montjoie@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>