linux/security/integrity/ima
Eric Biggers 877b5691f2 crypto: shash - remove shash_desc::flags
The flags field in 'struct shash_desc' never actually does anything.
The only ostensibly supported flag is CRYPTO_TFM_REQ_MAY_SLEEP.
However, no shash algorithm ever sleeps, making this flag a no-op.

With this being the case, inevitably some users who can't sleep wrongly
pass MAY_SLEEP.  These would all need to be fixed if any shash algorithm
actually started sleeping.  For example, the shash_ahash_*() functions,
which wrap a shash algorithm with the ahash API, pass through MAY_SLEEP
from the ahash API to the shash API.  However, the shash functions are
called under kmap_atomic(), so actually they're assumed to never sleep.

Even if it turns out that some users do need preemption points while
hashing large buffers, we could easily provide a helper function
crypto_shash_update_large() which divides the data into smaller chunks
and calls crypto_shash_update() and cond_resched() for each chunk.  It's
not necessary to have a flag in 'struct shash_desc', nor is it necessary
to make individual shash algorithms aware of this at all.

Therefore, remove shash_desc::flags, and document that the
crypto_shash_*() functions can be called from any context.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-04-25 15:38:12 +08:00
..
Kconfig x86/ima: define arch_get_ima_policy() for x86 2018-12-11 07:13:41 -05:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ima.h Merge branch 'next-tpm' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2019-03-10 17:37:29 -07:00
ima_api.c Merge branch 'next-general' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security 2018-12-27 12:04:52 -08:00
ima_appraise.c security: mark expected switch fall-throughs and add a missing break 2019-02-22 09:56:09 -08:00
ima_crypto.c crypto: shash - remove shash_desc::flags 2019-04-25 15:38:12 +08:00
ima_fs.c security: audit and remove any unnecessary uses of module.h 2018-12-12 14:58:51 -08:00
ima_init.c tpm: pass an array of tpm_extend_digest structures to tpm_pcr_extend() 2019-02-13 09:48:52 +02:00
ima_kexec.c mm: convert totalram_pages and totalhigh_pages variables to atomic 2018-12-28 12:11:47 -08:00
ima_main.c ima: define ima_post_create_tmpfile() hook and add missing call 2019-02-04 17:36:01 -05:00
ima_mok.c KEYS: Use structure to capture key restriction function and data 2017-04-04 14:10:10 -07:00
ima_policy.c audit/stable-5.1 PR 20190305 2019-03-07 12:20:11 -08:00
ima_queue.c tpm: pass an array of tpm_extend_digest structures to tpm_pcr_extend() 2019-02-13 09:48:52 +02:00
ima_template.c security/integrity: constify some read-only data 2018-10-10 12:56:15 -04:00
ima_template_lib.c security: mark expected switch fall-throughs and add a missing break 2019-02-22 09:56:09 -08:00
ima_template_lib.h ima: introduce ima_parse_buf() 2017-06-21 14:37:12 -04:00