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2016-03-17Merge branch 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6Linus Torvalds1-13/+11
Pull crypto update from Herbert Xu: "Here is the crypto update for 4.6: API: - Convert remaining crypto_hash users to shash or ahash, also convert blkcipher/ablkcipher users to skcipher. - Remove crypto_hash interface. - Remove crypto_pcomp interface. - Add crypto engine for async cipher drivers. - Add akcipher documentation. - Add skcipher documentation. Algorithms: - Rename crypto/crc32 to avoid name clash with lib/crc32. - Fix bug in keywrap where we zero the wrong pointer. Drivers: - Support T5/M5, T7/M7 SPARC CPUs in n2 hwrng driver. - Add PIC32 hwrng driver. - Support BCM6368 in bcm63xx hwrng driver. - Pack structs for 32-bit compat users in qat. - Use crypto engine in omap-aes. - Add support for sama5d2x SoCs in atmel-sha. - Make atmel-sha available again. - Make sahara hashing available again. - Make ccp hashing available again. - Make sha1-mb available again. - Add support for multiple devices in ccp. - Improve DMA performance in caam. - Add hashing support to rockchip" * 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (116 commits) crypto: qat - remove redundant arbiter configuration crypto: ux500 - fix checks of error code returned by devm_ioremap_resource() crypto: atmel - fix checks of error code returned by devm_ioremap_resource() crypto: qat - Change the definition of icp_qat_uof_regtype hwrng: exynos - use __maybe_unused to hide pm functions crypto: ccp - Add abstraction for device-specific calls crypto: ccp - CCP versioning support crypto: ccp - Support for multiple CCPs crypto: ccp - Remove check for x86 family and model crypto: ccp - memset request context to zero during import lib/mpi: use "static inline" instead of "extern inline" lib/mpi: avoid assembler warning hwrng: bcm63xx - fix non device tree compatibility crypto: testmgr - allow rfc3686 aes-ctr variants in fips mode. crypto: qat - The AE id should be less than the maximal AE number lib/mpi: Endianness fix crypto: rockchip - add hash support for crypto engine in rk3288 crypto: xts - fix compile errors crypto: doc - add skcipher API documentation crypto: doc - update AEAD AD handling ...
2016-02-07ext4 crypto: revalidate dentry after adding or removing the keyTheodore Ts'o1-0/+56
Add a validation check for dentries for encrypted directory to make sure we're not caching stale data after a key has been added or removed. Also check to make sure that status of the encryption key is updated when readdir(2) is executed. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2016-01-27ext4: Use skcipherHerbert Xu1-13/+11
This patch replaces uses of ablkcipher with skcipher. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
2015-12-07ext4: provide ext4_issue_zeroout()Jan Kara1-4/+2
Create new function ext4_issue_zeroout() to zeroout contiguous (both logically and physically) part of inode data. We will need to issue zeroout when extent structure is not readily available and this function will allow us to do it without making up fake extent structures. Signed-off-by: Jan Kara <jack@suse.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-11-26ext4: fix an endianness bug in ext4_encrypted_zeroout()Al Viro1-1/+1
ex->ee_block is not host-endian (note that accesses of other fields of *ex right next to that line go through the helpers that do proper conversion from little-endian to host-endian; it might make sense to add similar for ->ee_block to avoid reintroducing that kind of bugs...) Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-10-03ext4 crypto: fix bugs in ext4_encrypted_zeroout()Theodore Ts'o1-4/+19
Fix multiple bugs in ext4_encrypted_zeroout(), including one that could cause us to write an encrypted zero page to the wrong location on disk, potentially causing data and file system corruption. Fortunately, this tends to only show up in stress tests, but even with these fixes, we are seeing some test failures with generic/127 --- but these are now caused by data failures instead of metadata corruption. Since ext4_encrypted_zeroout() is only used for some optimizations to keep the extent tree from being too fragmented, and ext4_encrypted_zeroout() itself isn't all that optimized from a time or IOPS perspective, disable the extent tree optimization for encrypted inodes for now. This prevents the data corruption issues reported by generic/127 until we can figure out what's going wrong. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
2015-10-03ext4 crypto: replace some BUG_ON()'s with error checksTheodore Ts'o1-1/+0
Buggy (or hostile) userspace should not be able to cause the kernel to crash. Signed-off-by: Theodore Ts'o <tytso@mit.edu> Cc: stable@vger.kernel.org
2015-10-03ext4 crypto: ext4_page_crypto() doesn't need a encryption contextTheodore Ts'o1-23/+5
Since ext4_page_crypto() doesn't need an encryption context (at least not any more), this allows us to simplify a number function signature and also allows us to avoid needing to allocate a context in ext4_block_write_begin(). It also means we no longer need a separate ext4_decrypt_one() function. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-08ext4 crypto: fix ext4_get_crypto_ctx()'s calling convention in ext4_decrypt_oneTheodore Ts'o1-2/+2
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-06-03ext4 crypto: allocate bounce pages using GFP_NOWAITTheodore Ts'o1-21/+6
Previously we allocated bounce pages using a combination of alloc_page() and mempool_alloc() with the __GFP_WAIT bit set. Instead, use mempool_alloc() with GFP_NOWAIT. The mempool_alloc() function will try using alloc_pages() initially, and then only use the mempool reserve of pages if alloc_pages() is unable to fulfill the request. This minimizes the the impact on the mm layer when we need to do a large amount of writeback of encrypted files, as Jaeguk Kim had reported that under a heavy fio workload on a system with restricted amounts memory (which unfortunately, includes many mobile handsets), he had observed the the OOM killer getting triggered several times. Using GFP_NOWAIT If the mempool_alloc() function fails, we will retry the page writeback at a later time; the function of the mempool is to ensure that we can writeback at least 32 pages at a time, so we can more efficiently dispatch I/O under high memory pressure situations. In the future we should make this be a tunable so we can determine the best tradeoff between permanently sequestering memory and the ability to quickly launder pages so we can free up memory quickly when necessary. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-05-31ext4 crypto: handle unexpected lack of encryption keysTheodore Ts'o1-1/+2
Fix up attempts by users to try to write to a file when they don't have access to the encryption key. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-05-31ext4 crypto: fix memory leaks in ext4_encrypted_zerooutTheodore Ts'o1-31/+31
ext4_encrypted_zeroout() could end up leaking a bio and bounce page. Fortunately it's not used much. While we're fixing things up, refactor out common code into the static function alloc_bounce_page() and fix up error handling if mempool_alloc() fails. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-05-31ext4 crypto: use per-inode tfm structureTheodore Ts'o1-60/+4
As suggested by Herbert Xu, we shouldn't allocate a new tfm each time we read or write a page. Instead we can use a single tfm hanging off the inode's crypt_info structure for all of our encryption needs for that inode, since the tfm can be used by multiple crypto requests in parallel. Also use cmpxchg() to avoid races that could result in crypt_info structure getting doubly allocated or doubly freed. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-05-31ext4 crypto: shrink size of the ext4_crypto_ctx structureTheodore Ts'o1-21/+10
Some fields are only used when the crypto_ctx is being used on the read path, some are only used on the write path, and some are only used when the structure is on free list. Optimize memory use by using a union. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-05-18ext4 crypto: get rid of ci_mode from struct ext4_crypt_infoTheodore Ts'o1-6/+5
The ci_mode field was superfluous, and getting rid of it gets rid of an unused hole in the structure. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-05-18ext4 crypto: use slab cachesTheodore Ts'o1-31/+29
Use slab caches the ext4_crypto_ctx and ext4_crypt_info structures for slighly better memory efficiency and debuggability. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-05-18ext4 crypto: reorganize how we store keys in the inodeTheodore Ts'o1-4/+5
This is a pretty massive patch which does a number of different things: 1) The per-inode encryption information is now stored in an allocated data structure, ext4_crypt_info, instead of directly in the node. This reduces the size usage of an in-memory inode when it is not using encryption. 2) We drop the ext4_fname_crypto_ctx entirely, and use the per-inode encryption structure instead. This remove an unnecessary memory allocation and free for the fname_crypto_ctx as well as allowing us to reuse the ctfm in a directory for multiple lookups and file creations. 3) We also cache the inode's policy information in the ext4_crypt_info structure so we don't have to continually read it out of the extended attributes. 4) We now keep the keyring key in the inode's encryption structure instead of releasing it after we are done using it to derive the per-inode key. This allows us to test to see if the key has been revoked; if it has, we prevent the use of the derived key and free it. 5) When an inode is released (or when the derived key is freed), we will use memset_explicit() to zero out the derived key, so it's not left hanging around in memory. This implies that when a user logs out, it is important to first revoke the key, and then unlink it, and then finally, to use "echo 3 > /proc/sys/vm/drop_caches" to release any decrypted pages and dcache entries from the system caches. 6) All this, and we also shrink the number of lines of code by around 100. :-) Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-05-18ext4 crypto: separate kernel and userspace structure for the keyTheodore Ts'o1-9/+9
Use struct ext4_encryption_key only for the master key passed via the kernel keyring. For internal kernel space users, we now use struct ext4_crypt_info. This will allow us to put information from the policy structure so we can cache it and avoid needing to constantly looking up the extended attribute. We will do this in a spearate patch. This patch is mostly mechnical to make it easier for patch review. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
2015-04-12ext4 crypto: add ext4 encryption facilitiesMichael Halcrow1-0/+558
On encrypt, we will re-assign the buffer_heads to point to a bounce page rather than the control_page (which is the original page to write that contains the plaintext). The block I/O occurs against the bounce page. On write completion, we re-assign the buffer_heads to the original plaintext page. On decrypt, we will attach a read completion callback to the bio struct. This read completion will decrypt the read contents in-place prior to setting the page up-to-date. The current encryption mode, AES-256-XTS, lacks cryptographic integrity. AES-256-GCM is in-plan, but we will need to devise a mechanism for handling the integrity data. Signed-off-by: Michael Halcrow <mhalcrow@google.com> Signed-off-by: Ildar Muslukhov <ildarm@google.com> Signed-off-by: Theodore Ts'o <tytso@mit.edu>