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2020-08-07mm, treewide: rename kzfree() to kfree_sensitive()Waiman Long
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>
2020-07-16crypto: algapi - add NEED_FALLBACK to INHERITED_FLAGSEric Biggers
CRYPTO_ALG_NEED_FALLBACK is handled inconsistently. When it's requested to be clear, some templates propagate that request to child algorithms, while others don't. It's apparently desired for NEED_FALLBACK to be propagated, to avoid deadlocks where a module tries to load itself while it's being initialized, and to avoid unnecessarily complex fallback chains where we have e.g. cbc-aes-$driver falling back to cbc(aes-$driver) where aes-$driver itself falls back to aes-generic, instead of cbc-aes-$driver simply falling back to cbc(aes-generic). There have been a number of fixes to this effect: commit 89027579bc6c ("crypto: xts - Propagate NEED_FALLBACK bit") commit d2c2a85cfe82 ("crypto: ctr - Propagate NEED_FALLBACK bit") commit e6c2e65c70a6 ("crypto: cbc - Propagate NEED_FALLBACK bit") But it seems that other templates can have the same problems too. To avoid this whack-a-mole, just add NEED_FALLBACK to INHERITED_FLAGS so that it's always inherited. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-07-16crypto: algapi - use common mechanism for inheriting flagsEric Biggers
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 <mpatocka@redhat.com> (https://lore.kernel.org/r/alpine.LRH.2.02.2006301414580.30526@file01.intranet.prod.int.rdu2.redhat.com). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09crypto: algapi - enforce that all instances have a ->free() methodEric Biggers
All instances need to have a ->free() method, but people could forget to set it and then not notice if the instance is never unregistered. To help detect this bug earlier, don't allow an instance without a ->free() method to be registered, and complain loudly if someone tries to do it. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09crypto: cipher - make crypto_spawn_cipher() take a crypto_cipher_spawnEric Biggers
Now that all users of single-block cipher spawns have been converted to use 'struct crypto_cipher_spawn' rather than the less specifically typed 'struct crypto_spawn', make crypto_spawn_cipher() take a pointer to a 'struct crypto_cipher_spawn' rather than a 'struct crypto_spawn'. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09crypto: skcipher - use crypto_grab_cipher() and simplify error pathsEric Biggers
Make skcipher_alloc_instance_simple() use the new function crypto_grab_cipher() to initialize its cipher spawn. This is needed to make all spawns be initialized in a consistent way. 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 <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09crypto: algapi - pass instance to crypto_grab_spawn()Eric Biggers
Currently, crypto_spawn::inst is first used temporarily to pass the instance to crypto_grab_spawn(). Then crypto_init_spawn() overwrites it with crypto_spawn::next, which shares the same union. Finally, crypto_spawn::inst is set again when the instance is registered. Make this less convoluted by just passing the instance as an argument to crypto_grab_spawn() instead. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09crypto: skcipher - pass instance to crypto_grab_skcipher()Eric Biggers
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 <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09crypto: remove propagation of CRYPTO_TFM_RES_* flagsEric Biggers
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 <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2020-01-09crypto: remove CRYPTO_TFM_RES_BAD_KEY_LENEric Biggers
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>
2020-01-09crypto: skcipher - remove skcipher_walk_aead()Eric Biggers
skcipher_walk_aead() is unused and is identical to skcipher_walk_aead_encrypt(), so remove it. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-27crypto: skcipher - Add skcipher_ialg_simple helperHerbert Xu
This patch introduces the skcipher_ialg_simple helper which fetches the crypto_alg structure from a simple skcipher instance's spawn. This allows us to remove the third argument from the function skcipher_alloc_instance_simple. In doing so the reference count to the algorithm is now maintained by the Crypto API and the caller no longer needs to drop the alg refcount. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-11crypto: skcipher - remove crypto_skcipher_extsize()Eric Biggers
Due to the removal of the blkcipher and ablkcipher algorithm types, crypto_skcipher_extsize() now simply calls crypto_alg_extsize(). So remove it and just use crypto_alg_extsize(). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-11crypto: skcipher - remove crypto_skcipher::decryptEric Biggers
Due to the removal of the blkcipher and ablkcipher algorithm types, crypto_skcipher::decrypt is now redundant since it always equals crypto_skcipher_alg(tfm)->decrypt. Remove it and update crypto_skcipher_decrypt() accordingly. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-11crypto: skcipher - remove crypto_skcipher::encryptEric Biggers
Due to the removal of the blkcipher and ablkcipher algorithm types, crypto_skcipher::encrypt is now redundant since it always equals crypto_skcipher_alg(tfm)->encrypt. Remove it and update crypto_skcipher_encrypt() accordingly. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-11crypto: skcipher - remove crypto_skcipher::setkeyEric Biggers
Due to the removal of the blkcipher and ablkcipher algorithm types, crypto_skcipher::setkey now always points to skcipher_setkey(). Simplify by removing this function pointer and instead just making skcipher_setkey() be crypto_skcipher_setkey() directly. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-11crypto: skcipher - remove crypto_skcipher::keysizeEric Biggers
Due to the removal of the blkcipher and ablkcipher algorithm types, crypto_skcipher::keysize is now redundant since it always equals crypto_skcipher_alg(tfm)->max_keysize. Remove it and update crypto_skcipher_default_keysize() accordingly. Also rename crypto_skcipher_default_keysize() to crypto_skcipher_max_keysize() to clarify that it specifically returns the maximum key size, not some unspecified "default". Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-12-11crypto: skcipher - remove crypto_skcipher::ivsizeEric Biggers
Due to the removal of the blkcipher and ablkcipher algorithm types, crypto_skcipher::ivsize is now redundant since it always equals crypto_skcipher_alg(tfm)->ivsize. Remove it and update crypto_skcipher_ivsize() accordingly. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-17crypto: ablkcipher - remove deprecated and unused ablkcipher supportArd Biesheuvel
Now that all users of the deprecated ablkcipher interface have been moved to the skcipher interface, ablkcipher is no longer used and can be removed. Reviewed-by: Eric Biggers <ebiggers@kernel.org> Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-01crypto: skcipher - remove the "blkcipher" algorithm typeEric Biggers
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 <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-01crypto: skcipher - rename crypto_skcipher_type2 to crypto_skcipher_typeEric Biggers
Now that the crypto_skcipher_type() function has been removed, there's no reason to call the crypto_type struct for skciphers "crypto_skcipher_type2". Rename it to simply "crypto_skcipher_type". Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-11-01crypto: skcipher - unify the crypto_has_skcipher*() functionsEric Biggers
crypto_has_skcipher() and crypto_has_skcipher2() do the same thing: they check for the availability of an algorithm of type skcipher, blkcipher, or ablkcipher, which also meets any non-type constraints the caller specified. And they have exactly the same prototype. Therefore, eliminate the redundancy by removing crypto_has_skcipher() and renaming crypto_has_skcipher2() to crypto_has_skcipher(). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-09-09crypto: skcipher - Unmap pages after an external errorHerbert Xu
skcipher_walk_done may be called with an error by internal or external callers. For those internal callers we shouldn't unmap pages but for external callers we must unmap any pages that are in use. This patch distinguishes between the two cases by checking whether walk->nbytes is zero or not. For internal callers, we now set walk->nbytes to zero prior to the call. For external callers, walk->nbytes has always been non-zero (as zero is used to indicate the termination of a walk). Reported-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Fixes: 5cde0af2a982 ("[CRYPTO] cipher: Added block cipher type") Cc: <stable@vger.kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-07-08Merge branch 'linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto updates from Herbert Xu: "Here is the crypto update for 5.3: API: - Test shash interface directly in testmgr - cra_driver_name is now mandatory Algorithms: - Replace arc4 crypto_cipher with library helper - Implement 5 way interleave for ECB, CBC and CTR on arm64 - Add xxhash - Add continuous self-test on noise source to drbg - Update jitter RNG Drivers: - Add support for SHA204A random number generator - Add support for 7211 in iproc-rng200 - Fix fuzz test failures in inside-secure - Fix fuzz test failures in talitos - Fix fuzz test failures in qat" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (143 commits) crypto: stm32/hash - remove interruptible condition for dma crypto: stm32/hash - Fix hmac issue more than 256 bytes crypto: stm32/crc32 - rename driver file crypto: amcc - remove memset after dma_alloc_coherent crypto: ccp - Switch to SPDX license identifiers crypto: ccp - Validate the the error value used to index error messages crypto: doc - Fix formatting of new crypto engine content crypto: doc - Add parameter documentation crypto: arm64/aes-ce - implement 5 way interleave for ECB, CBC and CTR crypto: arm64/aes-ce - add 5 way interleave routines crypto: talitos - drop icv_ool crypto: talitos - fix hash on SEC1. crypto: talitos - move struct talitos_edesc into talitos.h lib/scatterlist: Fix mapping iterator when sg->offset is greater than PAGE_SIZE crypto/NX: Set receive window credits to max number of CRBs in RxFIFO crypto: asymmetric_keys - select CRYPTO_HASH where needed crypto: serpent - mark __serpent_setkey_sbox noinline crypto: testmgr - dynamically allocate crypto_shash crypto: testmgr - dynamically allocate testvec_config crypto: talitos - eliminate unneeded 'done' functions at build time ...
2019-06-13crypto: skcipher - un-inline encrypt and decrypt functionsEric Biggers
crypto_skcipher_encrypt() and crypto_skcipher_decrypt() have grown to be more than a single indirect function call. They now also check whether a key has been set, and with CONFIG_CRYPTO_STATS=y they also update the crypto statistics. That can add up to a lot of bloat at every call site. Moreover, these always involve a function call anyway, which greatly limits the benefits of inlining. So change them to be non-inline. Signed-off-by: Eric Biggers <ebiggers@google.com> Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-05-30treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152Thomas Gleixner
Based on 1 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 3029 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-08crypto: skcipher - don't WARN on unprocessed data after slow walk stepEric Biggers
skcipher_walk_done() assumes it's a bug if, after the "slow" path is executed where the next chunk of data is processed via a bounce buffer, the algorithm says it didn't process all bytes. Thus it WARNs on this. However, this can happen legitimately when the message needs to be evenly divisible into "blocks" but isn't, and the algorithm has a 'walksize' greater than the block size. For example, ecb-aes-neonbs sets 'walksize' to 128 bytes and only supports messages evenly divisible into 16-byte blocks. If, say, 17 message bytes remain but they straddle scatterlist elements, the skcipher_walk code will take the "slow" path and pass the algorithm all 17 bytes in the bounce buffer. But the algorithm will only be able to process 16 bytes, triggering the WARN. Fix this by just removing the WARN_ON(). Returning -EINVAL, as the code already does, is the right behavior. This bug was detected by my patches that improve testmgr to fuzz algorithms against their generic implementation. Fixes: b286d8b1a690 ("crypto: skcipher - Add skcipher walk interface") Cc: <stable@vger.kernel.org> # v4.10+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-01-18crypto: skcipher - set CRYPTO_TFM_NEED_KEY if ->setkey() failsEric Biggers
Some algorithms have a ->setkey() method that is not atomic, in the sense that setting a key can fail after changes were already made to the tfm context. In this case, if a key was already set the tfm can end up in a state that corresponds to neither the old key nor the new key. For example, in lrw.c, if gf128mul_init_64k_bbe() fails due to lack of memory, then priv::table will be left NULL. After that, encryption with that tfm will cause a NULL pointer dereference. It's not feasible to make all ->setkey() methods atomic, especially ones that have to key multiple sub-tfms. Therefore, make the crypto API set CRYPTO_TFM_NEED_KEY if ->setkey() fails and the algorithm requires a key, to prevent the tfm from being used until a new key is set. [Cc stable mainly because when introducing the NEED_KEY flag I changed AF_ALG to rely on it; and unlike in-kernel crypto API users, AF_ALG previously didn't have this problem. So these "incompletely keyed" states became theoretically accessible via AF_ALG -- though, the opportunities for causing real mischief seem pretty limited.] Fixes: f8d33fac8480 ("crypto: skcipher - prevent using skciphers without setting key") Cc: <stable@vger.kernel.org> # v4.16+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2019-01-11crypto: skcipher - add helper for simple block cipher modesEric Biggers
The majority of skcipher templates (including both the existing ones and the ones remaining to be converted from the "blkcipher" API) just wrap a single block cipher algorithm. This includes cbc, cfb, ctr, ecb, kw, ofb, and pcbc. Add a helper function skcipher_alloc_instance_simple() that handles allocating an skcipher instance for this common case. Signed-off-by: Eric Biggers <ebiggers@google.com> Reviewed-by: Stephan Mueller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-23crypto: skcipher - remove remnants of internal IV generatorsEric Biggers
Remove dead code related to internal IV generators, which are no longer used since they've been replaced with the "seqiv" and "echainiv" templates. The removed code includes: - The "givcipher" (GIVCIPHER) algorithm type. No algorithms are registered with this type anymore, so it's unneeded. - The "const char *geniv" member of aead_alg, ablkcipher_alg, and blkcipher_alg. A few algorithms still set this, but it isn't used anymore except to show via /proc/crypto and CRYPTO_MSG_GETALG. Just hardcode "<default>" or "<none>" in those cases. - The 'skcipher_givcrypt_request' structure, which is never used. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-12-23crypto: skcipher - add might_sleep() to skcipher_walk_virt()Eric Biggers
skcipher_walk_virt() can still sleep even with atomic=true, since that only affects the later calls to skcipher_walk_done(). But, skcipher_walk_virt() only has to allocate memory for some input data layouts, so incorrectly calling it with preemption disabled can go undetected. Use might_sleep() so that it's detected reliably. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-11-09crypto: user - clean up report structure copyingEric Biggers
There have been a pretty ridiculous number of issues with initializing the report structures that are copied to userspace by NETLINK_CRYPTO. Commit 4473710df1f8 ("crypto: user - Prepare for CRYPTO_MAX_ALG_NAME expansion") replaced some strncpy()s with strlcpy()s, thereby introducing information leaks. Later two other people tried to replace other strncpy()s with strlcpy() too, which would have introduced even more information leaks: - https://lore.kernel.org/patchwork/patch/954991/ - https://patchwork.kernel.org/patch/10434351/ Commit cac5818c25d0 ("crypto: user - Implement a generic crypto statistics") also uses the buggy strlcpy() approach and therefore leaks uninitialized memory to userspace. A fix was proposed, but it was originally incomplete. Seeing as how apparently no one can get this right with the current approach, change all the reporting functions to: - Start by memsetting the report structure to 0. This guarantees it's always initialized, regardless of what happens later. - Initialize all strings using strscpy(). This is safe after the memset, ensures null termination of long strings, avoids unnecessary work, and avoids the -Wstringop-truncation warnings from gcc. - Use sizeof(var) instead of sizeof(type). This is more robust against copy+paste errors. For simplicity, also reuse the -EMSGSIZE return value from nla_put(). Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-09-28crypto: skcipher - Introduce crypto_sync_skcipherKees Cook
In preparation for removal of VLAs due to skcipher requests on the stack via SKCIPHER_REQUEST_ON_STACK() usage, this introduces the infrastructure for the "sync skcipher" tfm, which is for handling the on-stack cases of skcipher, which are always non-ASYNC and have a known limited request size. The crypto API additions: struct crypto_sync_skcipher (wrapper for struct crypto_skcipher) crypto_alloc_sync_skcipher() crypto_free_sync_skcipher() crypto_sync_skcipher_setkey() crypto_sync_skcipher_get_flags() crypto_sync_skcipher_set_flags() crypto_sync_skcipher_clear_flags() crypto_sync_skcipher_blocksize() crypto_sync_skcipher_ivsize() crypto_sync_skcipher_reqtfm() skcipher_request_set_sync_tfm() SYNC_SKCIPHER_REQUEST_ON_STACK() (with tfm type check) Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03crypto: skcipher - fix crash flushing dcache in error pathEric Biggers
scatterwalk_done() is only meant to be called after a nonzero number of bytes have been processed, since scatterwalk_pagedone() will flush the dcache of the *previous* page. But in the error case of skcipher_walk_done(), e.g. if the input wasn't an integer number of blocks, scatterwalk_done() was actually called after advancing 0 bytes. This caused a crash ("BUG: unable to handle kernel paging request") during '!PageSlab(page)' on architectures like arm and arm64 that define ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE, provided that the input was page-aligned as in that case walk->offset == 0. Fix it by reorganizing skcipher_walk_done() to skip the scatterwalk_advance() and scatterwalk_done() if an error has occurred. This bug was found by syzkaller fuzzing. Reproducer, assuming ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE: #include <linux/if_alg.h> #include <sys/socket.h> #include <unistd.h> int main() { struct sockaddr_alg addr = { .salg_type = "skcipher", .salg_name = "cbc(aes-generic)", }; char buffer[4096] __attribute__((aligned(4096))) = { 0 }; int fd; fd = socket(AF_ALG, SOCK_SEQPACKET, 0); bind(fd, (void *)&addr, sizeof(addr)); setsockopt(fd, SOL_ALG, ALG_SET_KEY, buffer, 16); fd = accept(fd, NULL, NULL); write(fd, buffer, 15); read(fd, buffer, 15); } Reported-by: Liu Chao <liuchao741@huawei.com> Fixes: b286d8b1a690 ("crypto: skcipher - Add skcipher walk interface") Cc: <stable@vger.kernel.org> # v4.10+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03crypto: skcipher - remove unnecessary setting of walk->nbytesEric Biggers
Setting 'walk->nbytes = walk->total' in skcipher_walk_first() doesn't make sense because actually walk->nbytes needs to be set to the length of the first step in the walk, which may be less than walk->total. This is done by skcipher_walk_next() which is called immediately afterwards. Also walk->nbytes was already set to 0 in skcipher_walk_skcipher(), which is a better default value in case it's forgotten to be set later. Therefore, remove the unnecessary assignment to walk->nbytes. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-08-03crypto: skcipher - fix aligning block size in skcipher_copy_iv()Eric Biggers
The ALIGN() macro needs to be passed the alignment, not the alignmask (which is the alignment minus 1). Fixes: b286d8b1a690 ("crypto: skcipher - Add skcipher walk interface") Cc: <stable@vger.kernel.org> # v4.10+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-07-01crypto: skcipher - remove the exporting of skcipher_walk_nextDenis Efremov
The function skcipher_walk_next declared as static and marked as EXPORT_SYMBOL_GPL. It's a bit confusing for internal function to be exported. The area of visibility for such function is its .c file and all other modules. Other *.c files of the same module can't use it, despite all other modules can. Relying on the fact that this is the internal function and it's not a crucial part of the API, the patch just removes the EXPORT_SYMBOL_GPL marking of skcipher_walk_next. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Denis Efremov <efremov@linux.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2018-01-12crypto: skcipher - prevent using skciphers without setting keyEric Biggers
Similar to what was done for the hash API, update the skcipher API to track whether each transform has been keyed, and reject encryption/decryption if a key is needed but one hasn't been set. This isn't as important as the equivalent fix for the hash API because symmetric ciphers almost always require a key (the "null cipher" is the only exception), so are unlikely to be used without one. Still, tracking the key will prevent accidental unkeyed use. algif_skcipher also had to track the key anyway, so the new flag replaces that and simplifies the algif_skcipher implementation. Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-12-11crypto: skcipher - set walk.iv for zero-length inputsEric Biggers
All the ChaCha20 algorithms as well as the ARM bit-sliced AES-XTS algorithms call skcipher_walk_virt(), then access the IV (walk.iv) before checking whether any bytes need to be processed (walk.nbytes). But if the input is empty, then skcipher_walk_virt() doesn't set the IV, and the algorithms crash trying to use the uninitialized IV pointer. Fix it by setting the IV earlier in skcipher_walk_virt(). Also fix it for the AEAD walk functions. This isn't a perfect solution because we can't actually align the IV to ->cra_alignmask unless there are bytes to process, for one because the temporary buffer for the aligned IV is freed by skcipher_walk_done(), which is only called when there are bytes to process. Thus, algorithms that require aligned IVs will still need to avoid accessing the IV when walk.nbytes == 0. Still, many algorithms/architectures are fine with IVs having any alignment, and even for those that aren't, a misaligned pointer bug is much less severe than an uninitialized pointer bug. This change also matches the behavior of the older blkcipher_walk API. Fixes: 0cabf2af6f5a ("crypto: skcipher - Fix crash on zero-length input") Reported-by: syzbot <syzkaller@googlegroups.com> Cc: <stable@vger.kernel.org> # v4.14+ Signed-off-by: Eric Biggers <ebiggers@google.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-11-28Merge branch 'linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6 Pull crypto fixes from Herbert Xu: - avoid potential bogus alignment for some AEAD operations - fix crash in algif_aead - avoid sleeping in softirq context with async af_alg * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: crypto: skcipher - Fix skcipher_walk_aead_common crypto: af_alg - remove locking in async callback crypto: algif_aead - skip SGL entries with NULL page
2017-11-25crypto: skcipher - Fix skcipher_walk_aead_commonOndrej Mosnáček
The skcipher_walk_aead_common function calls scatterwalk_copychunks on the input and output walks to skip the associated data. If the AD end at an SG list entry boundary, then after these calls the walks will still be pointing to the end of the skipped region. These offsets are later checked for alignment in skcipher_walk_next, so the skcipher_walk may detect the alignment incorrectly. This patch fixes it by calling scatterwalk_done after the copychunks calls to ensure that the offsets refer to the right SG list entry. Fixes: b286d8b1a690 ("crypto: skcipher - Add skcipher walk interface") Cc: <stable@vger.kernel.org> Signed-off-by: Ondrej Mosnacek <omosnacek@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-10-07crypto: skcipher - Fix crash on zero-length inputHerbert Xu
The skcipher walk interface doesn't handle zero-length input properly as the old blkcipher walk interface did. This is due to the fact that the length check is done too late. This patch moves the length check forward so that it does the right thing. Fixes: b286d8b1a690 ("crypto: skcipher - Add skcipher walk...") Cc: <stable@vger.kernel.org> Reported-by: Stephan Müller <smueller@chronox.de> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-05-18crypto: skcipher - Add missing API setkey checksHerbert Xu
The API setkey checks for key sizes and alignment went AWOL during the skcipher conversion. This patch restores them. Cc: <stable@vger.kernel.org> Fixes: 4e6c3df4d729 ("crypto: skcipher - Add low-level skcipher...") Reported-by: Baozeng <sploving1@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2017-01-13crypto: Replaced gcc specific attributes with macros from compiler.hGideon Israel Dsouza
Continuing from this commit: 52f5684c8e1e ("kernel: use macros from compiler.h instead of __attribute__((...))") I submitted 4 total patches. They are part of task I've taken up to increase compiler portability in the kernel. I've cleaned up the subsystems under /kernel /mm /block and /security, this patch targets /crypto. There is <linux/compiler.h> which provides macros for various gcc specific constructs. Eg: __weak for __attribute__((weak)). I've cleaned all instances of gcc specific attributes with the right macros for the crypto subsystem. I had to make one additional change into compiler-gcc.h for the case when one wants to use this: __attribute__((aligned) and not specify an alignment factor. From the gcc docs, this will result in the largest alignment for that data type on the target machine so I've named the macro __aligned_largest. Please advise if another name is more appropriate. Signed-off-by: Gideon Israel Dsouza <gidisrael@gmail.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-12-30crypto: skcipher - introduce walksize attribute for SIMD algosArd Biesheuvel
In some cases, SIMD algorithms can only perform optimally when allowed to operate on multiple input blocks in parallel. This is especially true for bit slicing algorithms, which typically take the same amount of time processing a single block or 8 blocks in parallel. However, other SIMD algorithms may benefit as well from bigger strides. So add a walksize attribute to the skcipher algorithm definition, and wire it up to the skcipher walk API. To avoid confusion between the skcipher and AEAD attributes, rename the skcipher_walk chunksize attribute to 'stride', and set it from the walksize (in the skcipher case) or from the chunksize (in the AEAD case). Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-12-14crypto: skcipher - fix crash in virtual walkArd Biesheuvel
The new skcipher walk API may crash in the following way. (Interestingly, the tcrypt boot time tests seem unaffected, while an explicit test using the module triggers it) Unable to handle kernel NULL pointer dereference at virtual address 00000000 ... [<ffff000008431d84>] __memcpy+0x84/0x180 [<ffff0000083ec0d0>] skcipher_walk_done+0x328/0x340 [<ffff0000080c5c04>] ctr_encrypt+0x84/0x100 [<ffff000008406d60>] simd_skcipher_encrypt+0x88/0x98 [<ffff0000083fa05c>] crypto_rfc3686_crypt+0x8c/0x98 [<ffff0000009b0900>] test_skcipher_speed+0x518/0x820 [tcrypt] [<ffff0000009b31c0>] do_test+0x1408/0x3b70 [tcrypt] [<ffff0000009bd050>] tcrypt_mod_init+0x50/0x1000 [tcrypt] [<ffff0000080838f4>] do_one_initcall+0x44/0x138 [<ffff0000081aee60>] do_init_module+0x68/0x1e0 [<ffff0000081524d0>] load_module+0x1fd0/0x2458 [<ffff000008152c38>] SyS_finit_module+0xe0/0xf0 [<ffff0000080836f0>] el0_svc_naked+0x24/0x28 This is due to the fact that skcipher_done_slow() may be entered with walk->buffer unset. Since skcipher_walk_done() already deals with the case where walk->buffer == walk->page, it appears to be the intention that walk->buffer point to walk->page after skcipher_next_slow(), so ensure that is the case. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-12-01crypto: skcipher - Add separate walker for AEAD decryptionHerbert Xu
The AEAD decrypt interface includes the authentication tag in req->cryptlen. Therefore we need to exlucde that when doing a walk over it. This patch adds separate walker functions for AEAD encryption and decryption. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
2016-11-30crypto: skcipher - fix crash in skcipher_walk_aead()Ard Biesheuvel
The new skcipher_walk_aead() may crash in the following way due to the walk flag SKCIPHER_WALK_PHYS not being cleared at the start of the walk: Unable to handle kernel NULL pointer dereference at virtual address 00000001 [..] Internal error: Oops: 96000044 [#1] PREEMPT SMP [..] PC is at skcipher_walk_next+0x208/0x450 LR is at skcipher_walk_next+0x1e4/0x450 pc : [<ffff2b93b7104e20>] lr : [<ffff2b93b7104dfc>] pstate: 40000045 sp : ffffb925fa517940 [...] [<ffff2b93b7104e20>] skcipher_walk_next+0x208/0x450 [<ffff2b93b710535c>] skcipher_walk_first+0x54/0x148 [<ffff2b93b7105664>] skcipher_walk_aead+0xd4/0x108 [<ffff2b93b6e77928>] ccm_encrypt+0x68/0x158 So clear the flag at the appropriate time. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-11-28crypto: skcipher - Add skcipher walk interfaceHerbert Xu
This patch adds the skcipher walk interface which replaces both blkcipher walk and ablkcipher walk. Just like blkcipher walk it can also be used for AEAD algorithms. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2016-07-18crypto: skcipher - Remove top-level givcipher interfaceHerbert Xu
This patch removes the old crypto_grab_skcipher helper and replaces it with crypto_grab_skcipher2. As this is the final entry point into givcipher this patch also removes all traces of the top-level givcipher interface, including all implicit IV generators such as chainiv. The bottom-level givcipher interface remains until the drivers using it are converted. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>