linux/crypto/api.c, branch v4.20

evm: Don't deadlock if a crypto algorithm is unavailable

2018-07-18T11:27:22Z

When EVM attempts to appraise a file signed with a crypto algorithm the kernel doesn't have support for, it will cause the kernel to trigger a module load. If the EVM policy includes appraisal of kernel modules this will in turn call back into EVM - since EVM is holding a lock until the crypto initialisation is complete, this triggers a deadlock. Add a CRYPTO_NOLOAD flag and skip module loading if it's set, and add that flag in the EVM case in order to fail gracefully with an error message instead of deadlocking. Signed-off-by: Matthew Garrett Acked-by: Herbert Xu Signed-off-by: Mimi Zohar

crypto: api - fix finding algorithm currently being tested

2018-04-20T16:24:02Z

Commit eb02c38f0197 ("crypto: api - Keep failed instances alive") is making allocating crypto transforms sometimes fail with ELIBBAD, when multiple processes try to access encrypted files with fscrypt for the first time since boot. The problem is that the "request larval" for the algorithm is being mistaken for an algorithm which failed its tests. Fix it by only returning ELIBBAD for "non-larval" algorithms. Also don't leak a reference to the algorithm. Fixes: eb02c38f0197 ("crypto: api - Keep failed instances alive") Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: api - Keep failed instances alive

2018-03-30T17:32:58Z

This patch reverts commit 9c521a200bc3 ("crypto: api - remove instance when test failed") and fixes the underlying problem in a different way. To recap, prior to the reverted commit, an instance that fails a self-test is kept around. However, it would satisfy any new lookups against its name and therefore the system may accumlulate an unbounded number of failed instances for the same algorithm name. The reverted commit fixed it by unregistering the instance. Hoever, this still does not prevent the creation of the same failed instance over and over again each time the name is looked up. This patch fixes it by keeping the failed instance around, just as we would if it were a normal algorithm. However, the lookup code has been udpated so that we do not attempt to create another instance as long as this failed one is still registered. Of course, you could still force a new creation by deleting the instance from user-space. A new error (ELIBBAD) has been commandeered for this purpose and will be returned when all registered algorithm of a given name have failed the self-test. Signed-off-by: Herbert Xu

crypto: api - Make crypto_alg_lookup static

2018-03-30T17:32:58Z

The function crypto_alg_lookup is only usd within the crypto API and should be not be exported to the modules. This patch marks it as a static function. Signed-off-by: Herbert Xu

crypto: api - Remove unused crypto_type lookup function

2018-03-30T17:32:57Z

The lookup function in crypto_type was only used for the implicit IV generators which have been completely removed from the crypto API. This patch removes the lookup function as it is now useless. Signed-off-by: Herbert Xu

crypto: algapi - convert cra_refcnt to refcount_t

2018-01-05T07:43:09Z

Reference counters should use refcount_t rather than atomic_t, since the refcount_t implementation can prevent overflows, reducing the exploitability of reference leak bugs. crypto_alg.cra_refcount is a reference counter with the usual semantics, so switch it over to refcount_t. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: api - Unexport crypto_larval_lookup()

2017-12-22T08:29:06Z

crypto_larval_lookup() is not used outside of crypto/api.c, so unexport it and mark it 'static'. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: introduce crypto wait for async op

2017-11-03T14:11:18Z

Invoking a possibly async. crypto op and waiting for completion while correctly handling backlog processing is a common task in the crypto API implementation and outside users of it. This patch adds a generic implementation for doing so in preparation for using it across the board instead of hand rolled versions. Signed-off-by: Gilad Ben-Yossef CC: Eric Biggers CC: Jonathan Cameron Signed-off-by: Herbert Xu

sched/headers: Prepare to move signal wakeup & sigpending methods from into

2017-03-02T07:42:32Z

Fix up affected files that include this signal functionality via sched.h. 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: api - Do not clear type bits in crypto_larval_lookup

2016-11-28T13:23:18Z

Currently all bits not set in mask are cleared in crypto_larval_lookup. This is unnecessary as wherever the type bits are used it is always masked anyway. This patch removes the clearing so that we may use bits set in the type but not in the mask for special purposes, e.g., picking up internal algorithms. Signed-off-by: Herbert Xu