kernel/linux.git/fs/ecryptfs/crypto.c, branch v6.19.11

ecryptfs: Use MD5 library instead of crypto_shash

2025-10-31T09:12:35+00:00

eCryptfs uses MD5 for a couple unusual purposes: to "mix" the key into the IVs for file contents encryption (similar to ESSIV), and to prepend some key-dependent bytes to the plaintext when encrypting filenames (which is useless since eCryptfs encrypts the filenames with ECB). Currently, eCryptfs computes these MD5 hashes using the crypto_shash API. Update it to instead use the MD5 library API. This is simpler and faster: the library doesn't require memory allocations, can't fail, and provides direct access to MD5 without overhead such as indirect calls. To preserve the existing behavior of eCryptfs support being disabled when the kernel is booted with "fips=1", make ecryptfs_get_tree() check fips_enabled itself. Previously it relied on crypto_alloc_shash("md5") failing. I don't know for sure that this is actually needed; e.g., it could be argued that eCryptfs's use of MD5 isn't for a security purpose as far as FIPS is concerned. But this preserves the existing behavior. Tested by verifying that an existing eCryptfs can still be mounted with a kernel that has this commit, with all the files matching. Also tested creating a filesystem with this commit and mounting+reading it without. Signed-off-by: Eric Biggers Link: https://patch.msgid.link/20251011200010.193140-1-ebiggers@kernel.org Acked-by: Ard Biesheuvel Signed-off-by: Christian Brauner

ecryptfs: Pass the folio index to crypt_extent()

2024-11-05T16:20:00+00:00

We need to pass pages, not folios, to crypt_extent() as we may be working with a plain page rather than a folio. But we need to know the index in the file, so pass it in from the caller. Signed-off-by: Matthew Wilcox (Oracle) Link: https://lore.kernel.org/r/20241025190822.1319162-11-willy@infradead.org Signed-off-by: Christian Brauner

ecryptfs: Convert lower_offset_for_page() to take a folio

2024-11-05T16:20:00+00:00

Both callers have a folio, so pass it in and use folio->index instead of page->index. Signed-off-by: Matthew Wilcox (Oracle) Link: https://lore.kernel.org/r/20241025190822.1319162-10-willy@infradead.org Signed-off-by: Christian Brauner

ecryptfs: Convert ecryptfs_decrypt_page() to take a folio

2024-11-05T16:20:00+00:00

Both callers have a folio, so pass it in and use it throughout. Signed-off-by: Matthew Wilcox (Oracle) Link: https://lore.kernel.org/r/20241025190822.1319162-9-willy@infradead.org Signed-off-by: Christian Brauner

ecryptfs: Convert ecryptfs_encrypt_page() to take a folio

2024-11-05T16:19:59+00:00

All three callers have a folio, so pass it in and use it throughout. Signed-off-by: Matthew Wilcox (Oracle) Link: https://lore.kernel.org/r/20241025190822.1319162-8-willy@infradead.org Signed-off-by: Christian Brauner

move asm/unaligned.h to linux/unaligned.h

2024-10-02T21:23:23+00:00

asm/unaligned.h is always an include of asm-generic/unaligned.h; might as well move that thing to linux/unaligned.h and include that - there's nothing arch-specific in that header. auto-generated by the following: for i in `git grep -l -w asm/unaligned.h`; do sed -i -e "s/asm\/unaligned.h/linux\/unaligned.h/" $i done for i in `git grep -l -w asm-generic/unaligned.h`; do sed -i -e "s/asm-generic\/unaligned.h/linux\/unaligned.h/" $i done git mv include/asm-generic/unaligned.h include/linux/unaligned.h git mv tools/include/asm-generic/unaligned.h tools/include/linux/unaligned.h sed -i -e "/unaligned.h/d" include/asm-generic/Kbuild sed -i -e "s/__ASM_GENERIC/__LINUX/" include/linux/unaligned.h tools/include/linux/unaligned.h

fs: ecryptfs: replace deprecated strncpy with strscpy

2024-04-24T23:57:38+00:00

strncpy() is deprecated for use on NUL-terminated destination strings [1] and as such we should prefer more robust and less ambiguous string interfaces. A good alternative is strscpy() as it guarantees NUL-termination on the destination buffer. In crypto.c: We expect cipher_name to be NUL-terminated based on its use with the C-string format specifier %s and with other string apis like strlen(): | printk(KERN_ERR "Error attempting to initialize key TFM " | "cipher with name = [%s]; rc = [%d]\n", | tmp_tfm->cipher_name, rc); and | int cipher_name_len = strlen(cipher_name); In main.c: We can remove the manual NUL-byte assignments as well as the pointers to destinations (which I assume only existed to trim down on line length?) in favor of directly using the destination buffer which allows the compiler to get size information -- enabling the usage of the new 2-argument strscpy(). Note that this patch relies on the _new_ 2-argument versions of strscpy() and strscpy_pad() introduced in Commit e6584c3964f2f ("string: Allow 2-argument strscpy()"). Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1] Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2] Link: https://github.com/KSPP/linux/issues/90 Cc: Signed-off-by: Justin Stitt Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/20240321-strncpy-fs-ecryptfs-crypto-c-v1-1-d78b74c214ac@google.com Signed-off-by: Kees Cook

fs: Create a generic is_dot_dotdot() utility

2024-01-23T15:58:56+00:00

De-duplicate the same functionality in several places by hoisting the is_dot_dotdot() utility function into linux/fs.h. Suggested-by: Amir Goldstein Reviewed-by: Jeff Layton Reviewed-by: Amir Goldstein Acked-by: Christian Brauner Signed-off-by: Chuck Lever

fs/ecryptfs: Replace kmap() with kmap_local_page()

2023-07-10T12:36:10+00:00

kmap() has been deprecated in favor of kmap_local_page(). Therefore, replace kmap() with kmap_local_page() in fs/ecryptfs. There are two main problems with kmap(): (1) It comes with an overhead as the mapping space is restricted and protected by a global lock for synchronization and (2) it also requires global TLB invalidation when the kmap’s pool wraps and it might block when the mapping space is fully utilized until a slot becomes available. With kmap_local_page() the mappings are per thread, CPU local, can take page faults, and can be called from any context (including interrupts). It is faster than kmap() in kernels with HIGHMEM enabled. The tasks can be preempted and, when they are scheduled to run again, the kernel virtual addresses are restored and still valid. Obviously, thread locality implies that the kernel virtual addresses returned by kmap_local_page() are only valid in the context of the callers (i.e., they cannot be handed to other threads). The use of kmap_local_page() in fs/ecryptfs does not break the above-mentioned assumption, so it is allowed and preferred. Tested in a QEMU/KVM x86_32 VM, 6GB RAM, booting a kernel with HIGHMEM64GB enabled. Suggested-by: Ira Weiny Reviewed-by: Ira Weiny Signed-off-by: "Fabio M. De Francesco" Message-Id: <20230426172223.8896-2-fmdefrancesco@gmail.com> Signed-off-by: Christian Brauner

Merge tag 'v6.3-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6

2023-02-22T02:10:50+00:00

Pull crypto update from Herbert Xu: "API: - Use kmap_local instead of kmap_atomic - Change request callback to take void pointer - Print FIPS status in /proc/crypto (when enabled) Algorithms: - Add rfc4106/gcm support on arm64 - Add ARIA AVX2/512 support on x86 Drivers: - Add TRNG driver for StarFive SoC - Delete ux500/hash driver (subsumed by stm32/hash) - Add zlib support in qat - Add RSA support in aspeed" * tag 'v6.3-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (156 commits) crypto: x86/aria-avx - Do not use avx2 instructions crypto: aspeed - Fix modular aspeed-acry crypto: hisilicon/qm - fix coding style issues crypto: hisilicon/qm - update comments to match function crypto: hisilicon/qm - change function names crypto: hisilicon/qm - use min() instead of min_t() crypto: hisilicon/qm - remove some unused defines crypto: proc - Print fips status crypto: crypto4xx - Call dma_unmap_page when done crypto: octeontx2 - Fix objects shared between several modules crypto: nx - Fix sparse warnings crypto: ecc - Silence sparse warning tls: Pass rec instead of aead_req into tls_encrypt_done crypto: api - Remove completion function scaffolding tls: Remove completion function scaffolding tipc: Remove completion function scaffolding net: ipv6: Remove completion function scaffolding net: ipv4: Remove completion function scaffolding net: macsec: Remove completion function scaffolding dm: Remove completion function scaffolding ...