On Tue, Sep 22, 2020 at 8:45 AM Richard Guy Briggs <rgb(a)redhat.com> wrote:
When there are no audit rules registered, mandatory records (config,
etc.) are missing their accompanying records (syscall, proctitle, etc.).
This is due to audit context dummy set on syscall entry based on absence
of rules that signals that no other records are to be printed. Clear the dummy
bit if any record is generated, open coding this in audit_log_start().
The proctitle context and dummy checks are pointless since the
proctitle record will not be printed if no syscall records are printed.
The fds array is reset to -1 after the first syscall to indicate it
isn't valid any more, but was never set to -1 when the context was
allocated to indicate it wasn't yet valid.
Check ctx->pwd in audit_log_name().
The audit_inode* functions can be called without going through
getname_flags() or getname_kernel() that sets audit_names and cwd, so
set the cwd in audit_alloc_name() if it has not already been done so due to
audit_names being valid and purge all other audit_getcwd() calls.
Revert the LSM dump_common_audit_data() LSM_AUDIT_DATA_* cases from the
ghak96 patch since they are no longer necessary due to cwd coverage in
audit_alloc_name().
Thanks to bauen1 <j2468h(a)googlemail.com> for reporting LSM situations in
which context->cwd is not valid, inadvertantly fixed by the ghak96 patch.
Please see upstream github issue
https://github.com/linux-audit/audit-kernel/issues/120
This is also related to upstream github issue
https://github.com/linux-audit/audit-kernel/issues/96
Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com>
---
Chagelog:
v5:
- open code audit_clear_dummy() in audit_log_start()
- fix check for ctx->pwd in audit_log_name()
- open code _audit_getcwd() contents in audit_alloc_name()
- ditch all *audit_getcwd() calls
v4:
- resubmit after revert
v3:
- initialize fds[0] to -1
- init cwd for ghak96 LSM_AUDIT_DATA_NET:AF_UNIX case
- init cwd for audit_inode{,_child}
v2:
- unconditionally clear dummy
- create audit_clear_dummy accessor function
- remove proctitle context and dummy checks
include/linux/audit.h | 8 --------
kernel/audit.c | 3 +++
kernel/auditsc.c | 27 +++++++--------------------
security/lsm_audit.c | 5 -----
4 files changed, 10 insertions(+), 33 deletions(-)
I've gone over this revision a couple of times now and it looks okay,
but past experience is whispering in my ear that perhaps this is
better to wait on this for the next cycle so it gets a full set of
-rcX releases. Thoughts?
--
paul moore