0f6cf13697
commit 42e15d12070b4ff9af2b980f1b65774c2dab0507 upstream. If a userspace process reads (with O_DIRECT) multiple blocks into the same buffer, dm-crypt reports an authentication error [1]. The error is reported in a log and it may cause RAID leg being kicked out of the array. This commit fixes dm-crypt, so that if integrity verification fails, the data is read again into a kernel buffer (where userspace can't modify it) and the integrity tag is rechecked. If the recheck succeeds, the content of the kernel buffer is copied into the user buffer; if the recheck fails, an integrity error is reported. [1] https://people.redhat.com/~mpatocka/testcases/blk-auth-modify/read2.c Signed-off-by: Mikulas Patocka <mpatocka@redhat.com> Cc: stable@vger.kernel.org Signed-off-by: Mike Snitzer <snitzer@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.