linux_dsm_epyc7002/security/integrity/ima
Mimi Zohar f9b2a735bd ima: audit log files opened with O_DIRECT flag
Files are measured or appraised based on the IMA policy.  When a
file, in policy, is opened with the O_DIRECT flag, a deadlock
occurs.

The first attempt at resolving this lockdep temporarily removed the
O_DIRECT flag and restored it, after calculating the hash.  The
second attempt introduced the O_DIRECT_HAVELOCK flag. Based on this
flag, do_blockdev_direct_IO() would skip taking the i_mutex a second
time.  The third attempt, by Dmitry Kasatkin, resolves the i_mutex
locking issue, by re-introducing the IMA mutex, but uncovered
another problem.  Reading a file with O_DIRECT flag set, writes
directly to userspace pages.  A second patch allocates a user-space
like memory.  This works for all IMA hooks, except ima_file_free(),
which is called on __fput() to recalculate the file hash.

Until this last issue is addressed, do not 'collect' the
measurement for measuring, appraising, or auditing files opened
with the O_DIRECT flag set.  Based on policy, permit or deny file
access.  This patch defines a new IMA policy rule option named
'permit_directio'.  Policy rules could be defined, based on LSM
or other criteria, to permit specific applications to open files
with the O_DIRECT flag set.

Changelog v1:
- permit or deny file access based IMA policy rules

Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Acked-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Cc: <stable@vger.kernel.org>
2014-06-03 14:21:50 -05:00
..
ima_api.c ima: audit log files opened with O_DIRECT flag 2014-06-03 14:21:50 -05:00
ima_appraise.c ima: use static const char array definitions 2014-03-07 11:30:36 -05:00
ima_crypto.c ima: skip memory allocation for empty files 2014-03-07 12:15:48 -05:00
ima_fs.c integrity: fix checkpatch errors 2014-03-07 12:15:45 -05:00
ima_init.c security: integrity: Use a more current logging style 2014-03-07 12:15:21 -05:00
ima_main.c ima: audit log files opened with O_DIRECT flag 2014-06-03 14:21:50 -05:00
ima_policy.c ima: audit log files opened with O_DIRECT flag 2014-06-03 14:21:50 -05:00
ima_queue.c integrity: fix checkpatch errors 2014-03-07 12:15:45 -05:00
ima_template_lib.c ima: reduce memory usage when a template containing the n field is used 2014-03-07 11:32:30 -05:00
ima_template_lib.h ima: extend the measurement list to include the file signature 2013-10-31 20:19:35 -04:00
ima_template.c integrity: fix checkpatch errors 2014-03-07 12:15:45 -05:00
ima.h ima: restore the original behavior for sending data with ima template 2014-03-07 11:32:29 -05:00
Kconfig Revert "ima: define '_ima' as a builtin 'trusted' keyring" 2013-11-23 16:36:35 -08:00
Makefile ima: define template fields library and new helpers 2013-10-25 17:17:05 -04:00