Will register a new event tag by name and format, and return an
event-log-tags format response with the newly allocated tag.
If format is not specified, then nothing will be recorded, but
a pre-existing named entry will be listed. If name and format are
not specified, list all dynamic entries. If name=* list all
event log tag entries.
Stickiness through logd crash will be managed with the tmpfs file
/dev/event-log-tags and through a reboot with add_tag entries in
the pmsg last logcat event log. On debug builds we retain a
/data/misc/logd/event-log-tags file that aids stickiness and that
can be picked up by the bugreport.
If we detect truncation damage to /dev/event-log-tags, or to
/data/misc/logd/event-log-tags, rebuild file with a new first line
signature incorporating the time so mmap'd readers of the file can
detect the possible change in shape and order.
Manual testing:
Make sure nc (netcat) is built for the target platform on the host:
$ m nc
Then the following can be used to issue a request on the platform:
$ echo -n 'getEventTag name=<name> format="<format>"\0EXIT\0' |
> nc -U /dev/socket/logd
Test: gTest logd-unit-test --gtest_filter=getEventTag*
Bug: 31456426
Change-Id: I5dacc5f84a24d52dae09cca5ee1a3a9f9207f06d
Setup and then collect from the environment /proc/kmsg and /dev/kmsg
file descriptors. Do not do so for logcat --reinit.
Test: gTest logd-unit-tests, liblog-unit-tests and logcat-unit-tests
Bug: 32450474
Change-Id: Ied537ca561fcd4e71a9ad9c57398a23ba23f6ced
Add the following mount options to the /proc filesystem:
hidepid=2,gid=3009
This change blocks /proc access unless you're in group 3009
(aka AID_READPROC).
Please see
https://github.com/torvalds/linux/blob/master/Documentation/filesystems/proc.txt
for documentation on the hidepid option.
hidepid=2 is preferred over hidepid=1 since it leaks less information
and doesn't generate SELinux ptrace denials when trying to access
/proc without being in the proper group.
Add AID_READPROC to processes which need to access /proc entries for
other UIDs.
Bug: 23310674
Change-Id: I22bb55ff7b80ff722945e224845215196f09dafa
