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5 commits

Author SHA1 Message Date
Tom Cherry
802864c782 init: handle property messages asynchronously #2
A previous change moved property_service into its own thread, since
there was otherwise a deadlock whenever a process called by init would
try to set a property.  This new thread, however, would send a message
via a blocking socket to init for each property that it received,
since init may need to take action depending on which property it is.
Unfortunately, this means that the deadlock is still possible, the
only difference is the socket's buffer must be filled before init deadlocks.

This change, therefore, adds the following:
1) A lock for instructing init to reboot
2) A lock for waiting on properties
3) A lock for queueing new properties

A previous version of this change was reverted and added locks around
all service operations and allowed the property thread to spawn
services directly.  This was complex due to the fact that this code
was not designed to be multi-threaded.  It was reverted due to
apparent issues during reboot.  This change keeps a queue of processes
pending control messages, which it will then handle in the future.  It
is less flexible but safer.

Bug: 146877356
Bug: 148236233
Bug: 150863651
Bug: 151251827
Test: multiple reboot tests, safely restarting hwservicemanager
Change-Id: Ice773436e85d3bf636bb0a892f3f6002bdf996b6
2020-03-12 17:15:07 -07:00
Tom Cherry
832f9f1dbd Revert "init: handle property service callbacks asynchronously"
This is apparently causing problems with reboot.

This reverts commit 7205c62933.

Bug: 150863651
Test: build
Change-Id: Ib8a4835cdc8358a54c7acdebc5c95038963a0419
2020-03-10 11:53:11 -07:00
Tom Cherry
7205c62933 init: handle property service callbacks asynchronously
A previous change moved property_service into its own thread, since
there was otherwise a deadlock whenever a process called by init would
try to set a property.  This new thread, however, would send a message
via a blocking socket to init for each property that it received,
since init may need to take action depending on which property it is.
Unfortunately, this means that the deadlock is still possible, the
only difference is the socket's buffer must be filled before init deadlocks.

There are possible partial solutions here: the socket's buffer may be
increased or property_service may only send messages for the
properties that init will take action on, however all of these
solutions still lead to eventual deadlock.  The only complete solution
is to handle these messages asynchronously.

This change, therefore, adds the following:
1) A lock for instructing init to reboot
2) A lock for waiting on properties
3) A lock for queueing new properties
4) A lock for any actions with ServiceList or any Services, enforced
   through thread annotations, particularly since this code was not
   designed with the intention of being multi-threaded.

Bug: 146877356
Bug: 148236233
Test: boot
Test: kill hwservicemanager without deadlock
Change-Id: I84108e54217866205a48c45e8b59355012c32ea8
2020-02-20 14:58:06 -08:00
Tom Cherry
4772f1da47 init: check the arguments of builtins during the build
Host init verifier already checks that the names and number of
arguments for builtins are correct, but it can check more.  This
change ensures that property expansions are well formed, and that
arguments that can be parsed on the host are correct.  For example it
checks that UIDs and GIDs exist, that numerical values can be parsed,
and that rlimit strings are correct.

Test: build

Change-Id: Ied8882498a88a9f8324db6b8d1020aeeccc8177b
2019-08-01 10:54:47 -07:00
Tom Cherry
7fd3bc27ec Move ActionManager to its own file
Bug: 36970783
Test: build
Change-Id: I08fa39052236b462249f79de1d02bf02bdbf4c84
2018-02-14 16:37:09 -08:00