diff options
Diffstat (limited to 'pkg/sentry/kernel/thread_group.go')
| -rw-r--r-- | pkg/sentry/kernel/thread_group.go | 44 |
1 files changed, 27 insertions, 17 deletions
diff --git a/pkg/sentry/kernel/thread_group.go b/pkg/sentry/kernel/thread_group.go index 72568d296..0b34c0099 100644 --- a/pkg/sentry/kernel/thread_group.go +++ b/pkg/sentry/kernel/thread_group.go @@ -15,7 +15,6 @@ package kernel import ( - "sync" "sync/atomic" "gvisor.dev/gvisor/pkg/abi/linux" @@ -25,6 +24,7 @@ import ( ktime "gvisor.dev/gvisor/pkg/sentry/kernel/time" "gvisor.dev/gvisor/pkg/sentry/limits" "gvisor.dev/gvisor/pkg/sentry/usage" + "gvisor.dev/gvisor/pkg/sync" "gvisor.dev/gvisor/pkg/syserror" ) @@ -238,8 +238,8 @@ type ThreadGroup struct { // execed is protected by the TaskSet mutex. execed bool - // rscr is the thread group's RSEQ critical region. - rscr atomic.Value `state:".(*RSEQCriticalRegion)"` + // oldRSeqCritical is the thread group's old rseq critical region. + oldRSeqCritical atomic.Value `state:".(*OldRSeqCriticalRegion)"` // mounts is the thread group's mount namespace. This does not really // correspond to a "mount namespace" in Linux, but is more like a @@ -254,37 +254,44 @@ type ThreadGroup struct { // // tty is protected by the signal mutex. tty *TTY + + // oomScoreAdj is the thread group's OOM score adjustment. This is + // currently not used but is maintained for consistency. + // TODO(gvisor.dev/issue/1967) + // + // oomScoreAdj is accessed using atomic memory operations. + oomScoreAdj int32 } -// newThreadGroup returns a new, empty thread group in PID namespace ns. The +// NewThreadGroup returns a new, empty thread group in PID namespace pidns. The // thread group leader will send its parent terminationSignal when it exits. // The new thread group isn't visible to the system until a task has been // created inside of it by a successful call to TaskSet.NewTask. -func (k *Kernel) newThreadGroup(mounts *fs.MountNamespace, ns *PIDNamespace, sh *SignalHandlers, terminationSignal linux.Signal, limits *limits.LimitSet, monotonicClock *timekeeperClock) *ThreadGroup { +func (k *Kernel) NewThreadGroup(mntns *fs.MountNamespace, pidns *PIDNamespace, sh *SignalHandlers, terminationSignal linux.Signal, limits *limits.LimitSet) *ThreadGroup { tg := &ThreadGroup{ threadGroupNode: threadGroupNode{ - pidns: ns, + pidns: pidns, }, signalHandlers: sh, terminationSignal: terminationSignal, ioUsage: &usage.IO{}, limits: limits, - mounts: mounts, + mounts: mntns, } tg.itimerRealTimer = ktime.NewTimer(k.monotonicClock, &itimerRealListener{tg: tg}) tg.timers = make(map[linux.TimerID]*IntervalTimer) - tg.rscr.Store(&RSEQCriticalRegion{}) + tg.oldRSeqCritical.Store(&OldRSeqCriticalRegion{}) return tg } -// saveRscr is invoked by stateify. -func (tg *ThreadGroup) saveRscr() *RSEQCriticalRegion { - return tg.rscr.Load().(*RSEQCriticalRegion) +// saveOldRSeqCritical is invoked by stateify. +func (tg *ThreadGroup) saveOldRSeqCritical() *OldRSeqCriticalRegion { + return tg.oldRSeqCritical.Load().(*OldRSeqCriticalRegion) } -// loadRscr is invoked by stateify. -func (tg *ThreadGroup) loadRscr(rscr *RSEQCriticalRegion) { - tg.rscr.Store(rscr) +// loadOldRSeqCritical is invoked by stateify. +func (tg *ThreadGroup) loadOldRSeqCritical(r *OldRSeqCriticalRegion) { + tg.oldRSeqCritical.Store(r) } // SignalHandlers returns the signal handlers used by tg. @@ -301,7 +308,7 @@ func (tg *ThreadGroup) Limits() *limits.LimitSet { } // release releases the thread group's resources. -func (tg *ThreadGroup) release() { +func (tg *ThreadGroup) release(t *Task) { // Timers must be destroyed without holding the TaskSet or signal mutexes // since timers send signals with Timer.mu locked. tg.itimerRealTimer.Destroy() @@ -317,7 +324,9 @@ func (tg *ThreadGroup) release() { for _, it := range its { it.DestroyTimer() } - tg.mounts.DecRef() + if tg.mounts != nil { + tg.mounts.DecRef(t) + } } // forEachChildThreadGroupLocked indicates over all child ThreadGroups. @@ -357,7 +366,8 @@ func (tg *ThreadGroup) SetControllingTTY(tty *TTY, arg int32) error { // terminal is stolen, and all processes that had it as controlling // terminal lose it." - tty_ioctl(4) if tty.tg != nil && tg.processGroup.session != tty.tg.processGroup.session { - if !auth.CredentialsFromContext(tg.leader).HasCapability(linux.CAP_SYS_ADMIN) || arg != 1 { + // Stealing requires CAP_SYS_ADMIN in the root user namespace. + if creds := auth.CredentialsFromContext(tg.leader); !creds.HasCapabilityIn(linux.CAP_SYS_ADMIN, creds.UserNamespace.Root()) || arg != 1 { return syserror.EPERM } // Steal the TTY away. Unlike TIOCNOTTY, don't send signals. |