diff options
| author | Jamie Liu <jamieliu@google.com> | 2018-12-18 13:49:22 -0800 |
|---|---|---|
| committer | Shentubot <shentubot@google.com> | 2018-12-18 13:50:33 -0800 |
| commit | 898838e34d1b0c76405f3e7f7f5fa7f1a444da0e (patch) | |
| tree | 1df651c9cd69b5bc68cc750f2366cfd70eaee0d1 /pkg/sentry/mm/pma.go | |
| parent | 0759f3afee5b02d1f43b54f90111086cdc78338e (diff) | |
Fix mremap expansion with mm.checkInvariants = true.
Also remove useless RSS changes in mm.movePMAsLocked().
PiperOrigin-RevId: 226052996
Change-Id: If59fd259b93238fb2f15c1c8ebfeda14cb590a87
Diffstat (limited to 'pkg/sentry/mm/pma.go')
| -rw-r--r-- | pkg/sentry/mm/pma.go | 10 |
1 files changed, 5 insertions, 5 deletions
diff --git a/pkg/sentry/mm/pma.go b/pkg/sentry/mm/pma.go index 63c50f719..d102035d8 100644 --- a/pkg/sentry/mm/pma.go +++ b/pkg/sentry/mm/pma.go @@ -679,7 +679,7 @@ func Unpin(prs []PinnedRange) { // movePMAsLocked moves all pmas in oldAR to newAR. // // Preconditions: mm.activeMu must be locked for writing. oldAR.Length() != 0. -// oldAR.Length() == newAR.Length(). !oldAR.Overlaps(newAR). +// oldAR.Length() <= newAR.Length(). !oldAR.Overlaps(newAR). // mm.pmas.IsEmptyRange(newAR). oldAR and newAR must be page-aligned. func (mm *MemoryManager) movePMAsLocked(oldAR, newAR usermem.AddrRange) { if checkInvariants { @@ -689,8 +689,8 @@ func (mm *MemoryManager) movePMAsLocked(oldAR, newAR usermem.AddrRange) { if !newAR.WellFormed() || newAR.Length() <= 0 || !newAR.IsPageAligned() { panic(fmt.Sprintf("invalid newAR: %v", newAR)) } - if oldAR.Length() != newAR.Length() { - panic(fmt.Sprintf("old and new address ranges have different lengths: %v, %v", oldAR, newAR)) + if oldAR.Length() > newAR.Length() { + panic(fmt.Sprintf("old address range %v may contain pmas that will not fit in new address range %v", oldAR, newAR)) } if oldAR.Overlaps(newAR) { panic(fmt.Sprintf("old and new address ranges overlap: %v, %v", oldAR, newAR)) @@ -710,8 +710,9 @@ func (mm *MemoryManager) movePMAsLocked(oldAR, newAR usermem.AddrRange) { oldAR: pseg.Range(), pma: pseg.Value(), }) - mm.removeRSSLocked(pseg.Range()) pseg = mm.pmas.Remove(pseg).NextSegment() + // No RSS change is needed since we're re-inserting the same pmas + // below. } off := newAR.Start - oldAR.Start @@ -719,7 +720,6 @@ func (mm *MemoryManager) movePMAsLocked(oldAR, newAR usermem.AddrRange) { for i := range movedPMAs { mpma := &movedPMAs[i] pmaNewAR := usermem.AddrRange{mpma.oldAR.Start + off, mpma.oldAR.End + off} - mm.addRSSLocked(pmaNewAR) pgap = mm.pmas.Insert(pgap, pmaNewAR, mpma.pma).NextGap() } |