[scudo] Shuffle the regions am: 47ca44164b
Original change: https://android-review.googlesource.com/c/platform/external/scudo/+/2478537
Change-Id: If9c72095a0511fbc5a8bcb2de3db957a63ec3e5a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>
diff --git a/standalone/primary64.h b/standalone/primary64.h
index 3df8749..7868111 100644
--- a/standalone/primary64.h
+++ b/standalone/primary64.h
@@ -65,6 +65,7 @@
void init(s32 ReleaseToOsInterval) NO_THREAD_SAFETY_ANALYSIS {
DCHECK(isAligned(reinterpret_cast<uptr>(this), alignof(ThisT)));
DCHECK_EQ(PrimaryBase, 0U);
+
// Reserve the space required for the Primary.
PrimaryBase = reinterpret_cast<uptr>(map(
nullptr, PrimarySize, "scudo:primary_reserve", MAP_NOACCESS, &Data));
@@ -78,13 +79,15 @@
RegionInfo *Region = getRegionInfo(I);
// The actual start of a region is offset by a random number of pages
// when PrimaryEnableRandomOffset is set.
- Region->RegionBeg = getRegionBaseByClassId(I) +
+ Region->RegionBeg = (PrimaryBase + (I << Config::PrimaryRegionSizeLog)) +
(Config::PrimaryEnableRandomOffset
? ((getRandomModN(&Seed, 16) + 1) * PageSize)
: 0);
Region->RandState = getRandomU32(&Seed);
Region->ReleaseInfo.LastReleaseAtNs = Time;
}
+ shuffle(RegionInfoArray, NumClasses, &Seed);
+
setOption(Option::ReleaseInterval, static_cast<sptr>(ReleaseToOsInterval));
}
@@ -420,8 +423,10 @@
return &RegionInfoArray[ClassId];
}
- uptr getRegionBaseByClassId(uptr ClassId) const {
- return PrimaryBase + (ClassId << Config::PrimaryRegionSizeLog);
+ uptr getRegionBaseByClassId(uptr ClassId) {
+ return roundDown(getRegionInfo(ClassId)->RegionBeg - PrimaryBase,
+ RegionSize) +
+ PrimaryBase;
}
static CompactPtrT compactPtrInternal(uptr Base, uptr Ptr) {
