diff options
| -rw-r--r-- | pkg/sentry/kernel/semaphore/semaphore.go | 23 | ||||
| -rw-r--r-- | pkg/sentry/syscalls/linux/linux64.go | 4 | ||||
| -rw-r--r-- | pkg/sentry/syscalls/linux/sys_sem.go | 17 |
3 files changed, 40 insertions, 4 deletions
diff --git a/pkg/sentry/kernel/semaphore/semaphore.go b/pkg/sentry/kernel/semaphore/semaphore.go index c39ecfb8f..310762936 100644 --- a/pkg/sentry/kernel/semaphore/semaphore.go +++ b/pkg/sentry/kernel/semaphore/semaphore.go @@ -423,6 +423,29 @@ func (s *Set) GetPID(num int32, creds *auth.Credentials) (int32, error) { return sem.pid, nil } +// GetZeroWaiters returns number of waiters waiting for the sem to go to zero. +func (s *Set) GetZeroWaiters(num int32, creds *auth.Credentials) (uint16, error) { + s.mu.Lock() + defer s.mu.Unlock() + + // The calling process must have read permission on the semaphore set. + if !s.checkPerms(creds, fs.PermMask{Read: true}) { + return 0, syserror.EACCES + } + + sem := s.findSem(num) + if sem == nil { + return 0, syserror.ERANGE + } + var semzcnt uint16 + for w := sem.waiters.Front(); w != nil; w = w.Next() { + if w.value == 0 { + semzcnt++ + } + } + return semzcnt, nil +} + // ExecuteOps attempts to execute a list of operations to the set. It only // succeeds when all operations can be applied. No changes are made if it fails. // diff --git a/pkg/sentry/syscalls/linux/linux64.go b/pkg/sentry/syscalls/linux/linux64.go index 36902d177..650ca16e6 100644 --- a/pkg/sentry/syscalls/linux/linux64.go +++ b/pkg/sentry/syscalls/linux/linux64.go @@ -118,7 +118,7 @@ var AMD64 = &kernel.SyscallTable{ 63: syscalls.Supported("uname", Uname), 64: syscalls.Supported("semget", Semget), 65: syscalls.PartiallySupported("semop", Semop, "Option SEM_UNDO not supported.", nil), - 66: syscalls.PartiallySupported("semctl", Semctl, "Options IPC_INFO, SEM_INFO, SEM_STAT, SEM_STAT_ANY, GETNCNT, GETZCNT not supported.", nil), + 66: syscalls.PartiallySupported("semctl", Semctl, "Options IPC_INFO, SEM_INFO, SEM_STAT, SEM_STAT_ANY, GETNCNT not supported.", nil), 67: syscalls.Supported("shmdt", Shmdt), 68: syscalls.ErrorWithEvent("msgget", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) 69: syscalls.ErrorWithEvent("msgsnd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) @@ -619,7 +619,7 @@ var ARM64 = &kernel.SyscallTable{ 188: syscalls.ErrorWithEvent("msgrcv", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) 189: syscalls.ErrorWithEvent("msgsnd", syserror.ENOSYS, "", []string{"gvisor.dev/issue/135"}), // TODO(b/29354921) 190: syscalls.Supported("semget", Semget), - 191: syscalls.PartiallySupported("semctl", Semctl, "Options IPC_INFO, SEM_INFO, SEM_STAT, SEM_STAT_ANY, GETNCNT, GETZCNT not supported.", nil), + 191: syscalls.PartiallySupported("semctl", Semctl, "Options IPC_INFO, SEM_INFO, SEM_STAT, SEM_STAT_ANY, GETNCNT not supported.", nil), 192: syscalls.ErrorWithEvent("semtimedop", syserror.ENOSYS, "", []string{"gvisor.dev/issue/137"}), 193: syscalls.PartiallySupported("semop", Semop, "Option SEM_UNDO not supported.", nil), 194: syscalls.PartiallySupported("shmget", Shmget, "Option SHM_HUGETLB is not supported.", nil), diff --git a/pkg/sentry/syscalls/linux/sys_sem.go b/pkg/sentry/syscalls/linux/sys_sem.go index c2d4bf805..067f6be6d 100644 --- a/pkg/sentry/syscalls/linux/sys_sem.go +++ b/pkg/sentry/syscalls/linux/sys_sem.go @@ -138,12 +138,15 @@ func Semctl(t *kernel.Task, args arch.SyscallArguments) (uintptr, *kernel.Syscal return 0, nil, err + case linux.GETZCNT: + v, err := getSemzcnt(t, id, num) + return uintptr(v), nil, err + case linux.IPC_INFO, linux.SEM_INFO, linux.SEM_STAT, linux.SEM_STAT_ANY, - linux.GETNCNT, - linux.GETZCNT: + linux.GETNCNT: t.Kernel().EmitUnimplementedEvent(t) fallthrough @@ -258,3 +261,13 @@ func getPID(t *kernel.Task, id int32, num int32) (int32, error) { } return int32(tg.ID()), nil } + +func getSemzcnt(t *kernel.Task, id int32, num int32) (uint16, error) { + r := t.IPCNamespace().SemaphoreRegistry() + set := r.FindByID(id) + if set == nil { + return 0, syserror.EINVAL + } + creds := auth.CredentialsFromContext(t) + return set.GetZeroWaiters(num, creds) +} |