Shm segments can be marked for lazy destruction via shmctl(IPC_RMID),
which destroys a segment once it is no longer attached to any
processes. We were unconditionally decrementing the segment refcount
on shmctl(IPC_RMID) which allowed a user to force a segment to be
destroyed by repeatedly calling shmctl(IPC_RMID), with outstanding
memory maps to the segment.
This is problematic because the memory released by a segment destroyed
this way can be reused by a different process while remaining
accessible by the process with outstanding maps to the segment.
PiperOrigin-RevId: 219713660
Change-Id: I443ab838322b4fb418ed87b2722c3413ead21845
Added events for *ctl syscalls that may have multiple different commands.
For runsc, each syscall event is only logged once. For *ctl syscalls, use
the cmd as identifier, not only the syscall number.
PiperOrigin-RevId: 218015941
Change-Id: Ie3c19131ae36124861e9b492a7dbe1765d9e5e59
Rahat Mahmood
Fabricio Voznika
Ian Gudger