mirror of
https://github.com/hardkernel/linux.git
synced 2026-06-06 02:50:49 +09:00
1886ab01a3
With the patch to allow xattr/attr operations if a portable signature verification fails, cp and tar can copy all xattrs/attrs so that at the end of the process verification succeeds. However, it might happen that the xattrs/attrs are already set to the correct value (taken at signing time) and signature verification succeeds before the copy has completed. For example, an archive might contains files owned by root and the archive is extracted by root. Then, since portable signatures are immutable, all subsequent operations fail (e.g. fchown()), even if the operation is legitimate (does not alter the current value). This patch avoids this problem by reporting successful operation to user space when that operation does not alter the current value of xattrs/attrs. With this patch, the one that introduces evm_hmac_disabled() and the one that allows a metadata operation on the INTEGRITY_FAIL_IMMUTABLE error, EVM portable signatures can be used without disabling metadata verification (by setting EVM_ALLOW_METADATA_WRITES). Due to keeping metadata verification enabled, altering immutable metadata protected with a portable signature that was successfully verified will be denied (existing behavior). Reported-by: kernel test robot <lkp@intel.com> [implicit declaration of function] Signed-off-by: Roberto Sassu <roberto.sassu@huawei.com> Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com> Cc: Andreas Gruenbacher <agruenba@redhat.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
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.