From e50ee26207a99930be966bd48e04f5bccd85cc05 Mon Sep 17 00:00:00 2001 From: Jing Chen Date: Thu, 25 Feb 2021 12:54:36 -0800 Subject: Implement SEM_STAT_ANY cmd of semctl. PiperOrigin-RevId: 359591577 --- pkg/sentry/kernel/semaphore/semaphore.go | 18 +++++++++++++----- 1 file changed, 13 insertions(+), 5 deletions(-) (limited to 'pkg/sentry/kernel/semaphore') diff --git a/pkg/sentry/kernel/semaphore/semaphore.go b/pkg/sentry/kernel/semaphore/semaphore.go index db01e4a97..fe2ab1662 100644 --- a/pkg/sentry/kernel/semaphore/semaphore.go +++ b/pkg/sentry/kernel/semaphore/semaphore.go @@ -381,15 +381,24 @@ func (s *Set) Change(ctx context.Context, creds *auth.Credentials, owner fs.File // GetStat extracts semid_ds information from the set. func (s *Set) GetStat(creds *auth.Credentials) (*linux.SemidDS, error) { + // "The calling process must have read permission on the semaphore set." + return s.semStat(creds, fs.PermMask{Read: true}) +} + +// GetStatAny extracts semid_ds information from the set without requiring read access. +func (s *Set) GetStatAny(creds *auth.Credentials) (*linux.SemidDS, error) { + return s.semStat(creds, fs.PermMask{}) +} + +func (s *Set) semStat(creds *auth.Credentials, permMask fs.PermMask) (*linux.SemidDS, 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}) { + if !s.checkPerms(creds, permMask) { return nil, syserror.EACCES } - ds := &linux.SemidDS{ + return &linux.SemidDS{ SemPerm: linux.IPCPerm{ Key: uint32(s.key), UID: uint32(creds.UserNamespace.MapFromKUID(s.owner.UID)), @@ -402,8 +411,7 @@ func (s *Set) GetStat(creds *auth.Credentials) (*linux.SemidDS, error) { SemOTime: s.opTime.TimeT(), SemCTime: s.changeTime.TimeT(), SemNSems: uint64(s.Size()), - } - return ds, nil + }, nil } // SetVal overrides a semaphore value, waking up waiters as needed. -- cgit v1.2.3