BMC/Intel-BMC/linux.git/fs/crypto/bio.c, branch dev-5.4

fscrypt: decrypt only the needed blocks in __fscrypt_decrypt_bio()

2019-05-28T17:27:53+00:00

In __fscrypt_decrypt_bio(), only decrypt the blocks that actually comprise the bio, rather than assuming blocksize == PAGE_SIZE and decrypting the entirety of every page used in the bio. This is in preparation for allowing encryption on ext4 filesystems with blocksize != PAGE_SIZE. This is based on work by Chandan Rajendra. Reviewed-by: Chandan Rajendra Signed-off-by: Eric Biggers

fscrypt: support decrypting multiple filesystem blocks per page

2019-05-28T17:27:53+00:00

Rename fscrypt_decrypt_page() to fscrypt_decrypt_pagecache_blocks() and redefine its behavior to decrypt all filesystem blocks in the given region of the given page, rather than assuming that the region consists of just one filesystem block. Also remove the 'inode' and 'lblk_num' parameters, since they can be retrieved from the page as it's already assumed to be a pagecache page. This is in preparation for allowing encryption on ext4 filesystems with blocksize != PAGE_SIZE. This is based on work by Chandan Rajendra. Reviewed-by: Chandan Rajendra Signed-off-by: Eric Biggers

fscrypt: handle blocksize < PAGE_SIZE in fscrypt_zeroout_range()

2019-05-28T17:27:53+00:00

Adjust fscrypt_zeroout_range() to encrypt a block at a time rather than a page at a time, so that it works when blocksize < PAGE_SIZE. This isn't optimized for performance, but then again this function already wasn't optimized for performance. As a future optimization, we could submit much larger bios here. This is in preparation for allowing encryption on ext4 filesystems with blocksize != PAGE_SIZE. This is based on work by Chandan Rajendra. Reviewed-by: Chandan Rajendra Signed-off-by: Eric Biggers

fscrypt: rename fscrypt_do_page_crypto() to fscrypt_crypt_block()

2019-05-28T17:27:52+00:00

fscrypt_do_page_crypto() only does a single encryption or decryption operation, with a single logical block number (single IV). So it actually operates on a filesystem block, not a "page" per se. To reflect this, rename it to fscrypt_crypt_block(). Reviewed-by: Chandan Rajendra Signed-off-by: Eric Biggers

fscrypt: remove the "write" part of struct fscrypt_ctx

2019-05-28T17:27:52+00:00

Now that fscrypt_ctx is not used for writes, remove the 'w' fields. Reviewed-by: Chandan Rajendra Signed-off-by: Eric Biggers

fscrypt: simplify bounce page handling

2019-05-28T17:27:52+00:00

Currently, bounce page handling for writes to encrypted files is unnecessarily complicated. A fscrypt_ctx is allocated along with each bounce page, page_private(bounce_page) points to this fscrypt_ctx, and fscrypt_ctx::w::control_page points to the original pagecache page. However, because writes don't use the fscrypt_ctx for anything else, there's no reason why page_private(bounce_page) can't just point to the original pagecache page directly. Therefore, this patch makes this change. In the process, it also cleans up the API exposed to filesystems that allows testing whether a page is a bounce page, getting the pagecache page from a bounce page, and freeing a bounce page. Reviewed-by: Chandan Rajendra Signed-off-by: Eric Biggers

Merge tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt

2019-05-08T04:28:04+00:00

Pull fscrypt updates from Ted Ts'o: "Clean up fscrypt's dcache revalidation support, and other miscellaneous cleanups" * tag 'fscrypt_for_linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt: fscrypt: cache decrypted symlink target in ->i_link vfs: use READ_ONCE() to access ->i_link fscrypt: fix race where ->lookup() marks plaintext dentry as ciphertext fscrypt: only set dentry_operations on ciphertext dentries fs, fscrypt: clear DCACHE_ENCRYPTED_NAME when unaliasing directory fscrypt: fix race allowing rename() and link() of ciphertext dentries fscrypt: clean up and improve dentry revalidation fscrypt: use READ_ONCE() to access ->i_crypt_info fscrypt: remove WARN_ON_ONCE() when decryption fails fscrypt: drop inode argument from fscrypt_get_ctx()

block: remove the i argument to bio_for_each_segment_all

2019-04-30T15:26:13+00:00

We only have two callers that need the integer loop iterator, and they can easily maintain it themselves. Suggested-by: Matthew Wilcox Reviewed-by: Johannes Thumshirn Acked-by: David Sterba Reviewed-by: Hannes Reinecke Acked-by: Coly Li Reviewed-by: Matthew Wilcox Signed-off-by: Christoph Hellwig Signed-off-by: Jens Axboe

fscrypt: remove WARN_ON_ONCE() when decryption fails

2019-04-16T22:44:44+00:00

If decrypting a block fails, fscrypt did a WARN_ON_ONCE(). But WARN is meant for kernel bugs, which this isn't; this could be hit by fuzzers using fault injection, for example. Also, there is already a proper warning message logged in fscrypt_do_page_crypto(), so the WARN doesn't add much. Just remove the unnessary WARN. Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o

fscrypt: drop inode argument from fscrypt_get_ctx()

2019-04-16T22:37:25+00:00

The only reason the inode is being passed to fscrypt_get_ctx() is to verify that the encryption key is available. However, all callers already ensure this because if we get as far as trying to do I/O to an encrypted file without the key, there's already a bug. Therefore, remove this unnecessary argument. Signed-off-by: Eric Biggers Signed-off-by: Theodore Ts'o