logd: auditd: suppress multiple identical avc: messages to kmsg

Sends first and last of a series of 3 or more indentical avc:
messages to kmsg and adds 'duplicate messages suppressed'
for the last one in the set. eg:

[67.141658] type=1400 audit(1468852100.171:70): avc: ... tcontext=u:object_r:proc:s0 tclass=file
[67.141678] type=1400 audit(1468852107.494:71): avc: ... tcontext=u:object_r:cache_file:s0 tclass=dir
[67.535202] type=1400 audit(1468852107.498:74): avc: ... tcontext=u:object_r:cache_file:s0 tclass=dir duplicate messages suppressed
[67.535227] type=1400 audit(1468852107.888:75): avc: ... tcontext=u:object_r:proc_net:s0 tclass=file

One can look at the sequence numbers in the above example to see that
four identical message were produced, two were dropped.

ToDo: Evaluate multiple streams of duplicate messages.

Bug: 30118730
Change-Id: I31dcda7c8c42edfc7a8f1bf4d9e46284c74b3d18
1 file changed
tree: 4781a3b64551fa4283d3457148458e097c700453
  1. liblog/
  2. logcat/
  3. logd/
  4. logwrapper/