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Differential D116716

[OpenMP][Offloading] Fixed a crash caused by dereferencing nullptr
ClosedPublic

Authored by tianshilei1992 on Jan 5 2022, 5:42 PM.

Details

Reviewers
jdoerfert
ronlieb
Commits
rGaab62aab0431: [OpenMP][Offloading] Fixed a crash caused by dereferencing nullptr
Summary

In function DeviceTy::getTargetPointer, Entry could be nullptr because of
zero length array section. We need to check if it is a valid iterator before
using it.

Diff Detail

Revision Contents

PathSize
openmp/
libomptarget/
src/
4 lines

Diff 397780

openmp/libomptarget/src/device.cpp

Show First 20 Lines • Show All 299 Lines • ▼ Show 20 Lines if (NeedNewEvent)
Entry->setEvent(Event); Entry->setEvent(Event);
// We're done with the entry. Release the entry. // We're done with the entry. Release the entry.
Entry->unlock(); Entry->unlock();
} else { } else {
// Release the mapping table lock directly. // Release the mapping table lock directly.
DataMapMtx.unlock(); DataMapMtx.unlock();
// If not a host pointer and no present modifier, we need to wait for the // If not a host pointer and no present modifier, we need to wait for the
// event if it exists. // event if it exists.
if (!IsHostPtr && !HasPresentModifier) { // Note: Entry might be nullptr because of zero length array section.
if (Entry != HostDataToTargetListTy::iterator() && !IsHostPtr &&
!HasPresentModifier) {
Entry->lock(); Entry->lock();
void *Event = Entry->getEvent(); void *Event = Entry->getEvent();
if (Event) { if (Event) {
int Ret = waitEvent(Event, AsyncInfo); int Ret = waitEvent(Event, AsyncInfo);
Entry->unlock(); Entry->unlock();
if (Ret != OFFLOAD_SUCCESS) { if (Ret != OFFLOAD_SUCCESS) {
// If it fails to wait for the event, we need to return nullptr in // If it fails to wait for the event, we need to return nullptr in
// case of any data race. // case of any data race.
▲ Show 20 Lines • Show All 347 Lines • Show Last 20 Lines