kernel/linux.git/crypto/cryptd.c, branch v6.1.168

crypto: cryptd - Use request context instead of stack for sub-request

2022-12-31T12:32:33+00:00

[ Upstream commit 3a58c231172537f7b0e19d93ed33decd04f80eab ] cryptd is buggy as it tries to use sync_skcipher without going through the proper sync_skcipher interface. In fact it doesn't even need sync_skcipher since it's already a proper skcipher and can easily access the request context instead of using something off the stack. Fixes: 36b3875a97b8 ("crypto: cryptd - Remove VLA usage of skcipher") Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin

crypto: cryptd - Protect per-CPU resource by disabling BH.

2022-05-13T09:24:48+00:00

The access to cryptd_queue::cpu_queue is synchronized by disabling preemption in cryptd_enqueue_request() and disabling BH in cryptd_queue_worker(). This implies that access is allowed from BH. If cryptd_enqueue_request() is invoked from preemptible context _and_ soft interrupt then this can lead to list corruption since cryptd_enqueue_request() is not protected against access from soft interrupt. Replace get_cpu() in cryptd_enqueue_request() with local_bh_disable() to ensure BH is always disabled. Remove preempt_disable() from cryptd_queue_worker() since it is not needed because local_bh_disable() ensures synchronisation. Fixes: 254eff771441 ("crypto: cryptd - Per-CPU thread implementation...") Signed-off-by: Sebastian Andrzej Siewior Signed-off-by: Herbert Xu

crypto: algapi - use common mechanism for inheriting flags

2020-07-16T11:49:08+00:00

The flag CRYPTO_ALG_ASYNC is "inherited" in the sense that when a template is instantiated, the template will have CRYPTO_ALG_ASYNC set if any of the algorithms it uses has CRYPTO_ALG_ASYNC set. We'd like to add a second flag (CRYPTO_ALG_ALLOCATES_MEMORY) that gets "inherited" in the same way. This is difficult because the handling of CRYPTO_ALG_ASYNC is hardcoded everywhere. Address this by: - Add CRYPTO_ALG_INHERITED_FLAGS, which contains the set of flags that have these inheritance semantics. - Add crypto_algt_inherited_mask(), for use by template ->create() methods. It returns any of these flags that the user asked to be unset and thus must be passed in the 'mask' to crypto_grab_*(). - Also modify crypto_check_attr_type() to handle computing the 'mask' so that most templates can just use this. - Make crypto_grab_*() propagate these flags to the template instance being created so that templates don't have to do this themselves. Make crypto/simd.c propagate these flags too, since it "wraps" another algorithm, similar to a template. Based on a patch by Mikulas Patocka (https://lore.kernel.org/r/alpine.LRH.2.02.2006301414580.30526@file01.intranet.prod.int.rdu2.redhat.com). Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: cryptd - simplify error handling in cryptd_create_*()

2020-03-06T01:28:22+00:00

Simplify the error handling in the various cryptd_create_*() functions by taking advantage of crypto_grab_*() now handling an ERR_PTR() name and by taking advantage of crypto_drop_*() now accepting (as a no-op) a spawn that hasn't been grabbed yet. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: cryptd - convert to new way of freeing instances

2020-01-09T03:30:57+00:00

Convert the "cryptd" template to the new way of freeing instances, where a ->free() method is installed to the instance struct itself. This replaces the weakly-typed method crypto_template::free(). This will allow removing support for the old way of freeing instances. Note that the 'default' case in cryptd_free() was already unreachable. So, we aren't missing anything by keeping only the ahash and aead parts. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: cryptd - use crypto_grab_shash() and simplify error paths

2020-01-09T03:30:55+00:00

Make the cryptd template (in the hash case) use the new function crypto_grab_shash() to initialize its shash spawn. This is needed to make all spawns be initialized in a consistent way. This required making cryptd_create_hash() allocate the instance directly rather than use cryptd_alloc_instance(). Also simplify the error handling by taking advantage of crypto_drop_*() now accepting (as a no-op) spawns that haven't been initialized yet, and by taking advantage of crypto_grab_*() now handling ERR_PTR() names. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: aead - pass instance to crypto_grab_aead()

2020-01-09T03:30:54+00:00

Initializing a crypto_aead_spawn currently requires: 1. Set spawn->base.inst to point to the instance. 2. Call crypto_grab_aead(). But there's no reason for these steps to be separate, and in fact this unneeded complication has caused at least one bug, the one fixed by commit 6db43410179b ("crypto: adiantum - initialize crypto_spawn::inst") So just make crypto_grab_aead() take the instance as an argument. To keep the function calls from getting too unwieldy due to this extra argument, also introduce a 'mask' variable into the affected places which weren't already using one. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: skcipher - pass instance to crypto_grab_skcipher()

2020-01-09T03:30:54+00:00

Initializing a crypto_skcipher_spawn currently requires: 1. Set spawn->base.inst to point to the instance. 2. Call crypto_grab_skcipher(). But there's no reason for these steps to be separate, and in fact this unneeded complication has caused at least one bug, the one fixed by commit 6db43410179b ("crypto: adiantum - initialize crypto_spawn::inst") So just make crypto_grab_skcipher() take the instance as an argument. To keep the function calls from getting too unwieldy due to this extra argument, also introduce a 'mask' variable into the affected places which weren't already using one. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: remove propagation of CRYPTO_TFM_RES_* flags

2020-01-09T03:30:53+00:00

The CRYPTO_TFM_RES_* flags were apparently meant as a way to make the ->setkey() functions provide more information about errors. But these flags weren't actually being used or tested, and in many cases they weren't being set correctly anyway. So they've now been removed. Also, if someone ever actually needs to start better distinguishing ->setkey() errors (which is somewhat unlikely, as this has been unneeded for a long time), we'd be much better off just defining 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 CRYPTO_TFM_RES_MASK and all the unneeded logic that propagates these flags around. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu

crypto: skcipher - remove the "blkcipher" algorithm type

2019-11-01T05:38:32+00:00

Now that all "blkcipher" algorithms have been converted to "skcipher", remove the blkcipher algorithm type. The skcipher (symmetric key cipher) algorithm type was introduced a few years ago to replace both blkcipher and ablkcipher (synchronous and asynchronous block cipher). The advantages of skcipher include: - A much less confusing name, since none of these algorithm types have ever actually been for raw block ciphers, but rather for all length-preserving encryption modes including block cipher modes of operation, stream ciphers, and other length-preserving modes. - It unified blkcipher and ablkcipher into a single algorithm type which supports both synchronous and asynchronous implementations. Note, blkcipher already operated only on scatterlists, so the fact that skcipher does too isn't a regression in functionality. - Better type safety by using struct skcipher_alg, struct crypto_skcipher, etc. instead of crypto_alg, crypto_tfm, etc. - It sometimes simplifies the implementations of algorithms. Also, the blkcipher API was no longer being tested. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu