linux.git/crypto/mcryptd.c, branch v4.15

crypto: mcryptd - protect the per-CPU queue with a lock

2017-12-11T11:29:54+00:00

mcryptd_enqueue_request() grabs the per-CPU queue struct and protects
access to it with disabled preemption. Then it schedules a worker on the
same CPU. The worker in mcryptd_queue_worker() guards access to the same
per-CPU variable with disabled preemption.

If we take CPU-hotplug into account then it is possible that between
queue_work_on() and the actual invocation of the worker the CPU goes
down and the worker will be scheduled on _another_ CPU. And here the
preempt_disable() protection does not work anymore. The easiest thing is
to add a spin_lock() to guard access to the list.

Another detail: mcryptd_queue_worker() is not processing more than
MCRYPTD_BATCH invocation in a row. If there are still items left, then
it will invoke queue_work() to proceed with more later. *I* would
suggest to simply drop that check because it does not use a system
workqueue and the workqueue is already marked as "CPU_INTENSIVE". And if
preemption is required then the scheduler should do it.
However if queue_work() is used then the work item is marked as CPU
unbound. That means it will try to run on the local CPU but it may run
on another CPU as well. Especially with CONFIG_DEBUG_WQ_FORCE_RR_CPU=y.
Again, the preempt_disable() won't work here but lock which was
introduced will help.
In order to keep work-item on the local CPU (and avoid RR) I changed it
to queue_work_on().

Cc: stable@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior 
Signed-off-by: Herbert Xu

sched/headers: Prepare for new header dependencies before moving code to

2017-03-02T07:42:34+00:00

We are going to split  out of , which
will have to be picked up from other headers and a couple of .c files.

Create a trivial placeholder  file that just
maps to  to make this patch obviously correct and
bisectable.

Include the new header in the files that are going to need it.

Acked-by: Linus Torvalds 
Cc: Mike Galbraith 
Cc: Peter Zijlstra 
Cc: Thomas Gleixner 
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar

crypto: mcryptd - Check mcryptd algorithm compatibility

2016-12-07T11:55:37+00:00

Algorithms not compatible with mcryptd could be spawned by mcryptd
with a direct crypto_alloc_tfm invocation using a "mcryptd(alg)" name
construct.  This causes mcryptd to crash the kernel if an arbitrary
"alg" is incompatible and not intended to be used with mcryptd.  It is
an issue if AF_ALG tries to spawn mcryptd(alg) to expose it externally.
But such algorithms must be used internally and not be exposed.

We added a check to enforce that only internal algorithms are allowed
with mcryptd at the time mcryptd is spawning an algorithm.

Link: http://marc.info/?l=linux-crypto-vger&m=148063683310477&w=2
Cc: stable@vger.kernel.org
Reported-by: Mikulas Patocka 
Signed-off-by: Tim Chen 
Signed-off-by: Herbert Xu

crypto: squash lines for simple wrapper functions

2016-09-13T12:27:26+00:00

Remove unneeded variables and assignments.

Signed-off-by: Masahiro Yamada 
Signed-off-by: Herbert Xu

crypto: sha1-mb - async implementation for sha1-mb

2016-06-23T10:29:55+00:00

Herbert wants the sha1-mb algorithm to have an async implementation:
https://lkml.org/lkml/2016/4/5/286.
Currently, sha1-mb uses an async interface for the outer algorithm
and a sync interface for the inner algorithm. This patch introduces
a async interface for even the inner algorithm.

Signed-off-by: Megha Dey 
Signed-off-by: Tim Chen 
Signed-off-by: Herbert Xu

crypto: mcryptd - Fix load failure

2016-01-30T14:11:20+00:00

mcryptd_create_hash() fails by returning -EINVAL, causing any
driver using mcryptd to fail to load. It is because it needs
to set its statesize properly.

Signed-off-by: Rui Wang 
Signed-off-by: Herbert Xu

crypto: mcryptd - use list_first_entry_or_null()

2015-11-23T12:55:51+00:00

Simplify mcryptd_opportunistic_flush() with list_first_entry_or_null().

Signed-off-by: Geliang Tang 
Signed-off-by: Herbert Xu

crypto: mcryptd - process CRYPTO_ALG_INTERNAL

2015-03-31T13:21:13+00:00

The mcryptd is used as a wrapper around internal ciphers. Therefore,
the mcryptd must process the internal cipher by marking mcryptd as
internal if the underlying cipher is an internal cipher.

Signed-off-by: Stephan Mueller 
Signed-off-by: Herbert Xu

crypto: include crypto- module prefix in template

2014-11-26T12:06:30+00:00

This adds the module loading prefix "crypto-" to the template lookup
as well.

For example, attempting to load 'vfat(blowfish)' via AF_ALG now correctly
includes the "crypto-" prefix at every level, correctly rejecting "vfat":

	net-pf-38
	algif-hash
	crypto-vfat(blowfish)
	crypto-vfat(blowfish)-all
	crypto-vfat

Reported-by: Mathias Krause 
Signed-off-by: Kees Cook 
Acked-by: Mathias Krause 
Signed-off-by: Herbert Xu

crypto: mcryptd - mcryptd_flist can be static

2014-08-26T06:40:39+00:00

CC: Tim Chen 
CC: Herbert Xu 
Signed-off-by: Fengguang Wu 
Signed-off-by: Herbert Xu