Re: [PATCH V2] audit: shorten PATH cap values when zero

Since the vast majority of files (99.993% on a typical system) have no fcaps, display "0" instead of the full zero-padded 16 hex digits in the two PATH record cap_f* fields to save netlink bandwidth and disk space. Simply changing the format to %x won't work since the value is two (or possibly more in the future) 32-bit hexadecimal values concatenated and bits in higher order values will be misrepresented. Passes audit-testsuite and userspace tools already work fine. Please see the github issue tracker for more details https://github.com/linux-audit/audit-kernel/issues/101 Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; Acked-by: Steve Grubb <sgrubb(a)redhat.com&gt; --- Changelog: v2: - switch to cap_isclear() and condense logic kernel/audit.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/kernel/audit.c b/kernel/audit.c index 2a8058764aa6..55b2079145dc 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -2058,11 +2058,13 @@ void audit_log_cap(struct audit_buffer *ab, char *prefix, kernel_cap_t *cap) { int i; - audit_log_format(ab, " %s=", prefix); - CAP_FOR_EACH_U32(i) { - audit_log_format(ab, "%08x", - cap->cap[CAP_LAST_U32 - i]); + if (cap_isclear(*cap)) { + audit_log_format(ab, " %s=0", prefix); + return; } + audit_log_format(ab, " %s=", prefix); + CAP_FOR_EACH_U32(i) + audit_log_format(ab, "%08x", cap->cap[CAP_LAST_U32 - i]); } static void audit_log_fcaps(struct audit_buffer *ab, struct audit_names *name) -- 1.8.3.1