diff options
Diffstat (limited to 'src/runtime')
| -rw-r--r-- | src/runtime/map_noswiss.go | 28 | ||||
| -rw-r--r-- | src/runtime/map_noswiss_test.go | 4 |
2 files changed, 10 insertions, 22 deletions
diff --git a/src/runtime/map_noswiss.go b/src/runtime/map_noswiss.go index d7b8a5fe11..327f0c81e8 100644 --- a/src/runtime/map_noswiss.go +++ b/src/runtime/map_noswiss.go @@ -123,6 +123,7 @@ type hmap struct { buckets unsafe.Pointer // array of 2^B Buckets. may be nil if count==0. oldbuckets unsafe.Pointer // previous bucket array of half the size, non-nil only when growing nevacuate uintptr // progress counter for evacuation (buckets less than this have been evacuated) + clearSeq uint64 extra *mapextra // optional fields } @@ -176,6 +177,7 @@ type hiter struct { i uint8 bucket uintptr checkBucket uintptr + clearSeq uint64 } // bucketShift returns 1<<b, optimized for code generation. @@ -887,10 +889,11 @@ func mapiterinit(t *maptype, h *hmap, it *hiter) { return } - if unsafe.Sizeof(hiter{})/goarch.PtrSize != 12 { + if unsafe.Sizeof(hiter{}) != 8+12*goarch.PtrSize { throw("hash_iter size incorrect") // see cmd/compile/internal/reflectdata/reflect.go } it.h = h + it.clearSeq = h.clearSeq // grab snapshot of bucket state it.B = h.B @@ -1022,8 +1025,9 @@ next: } } } - if (b.tophash[offi] != evacuatedX && b.tophash[offi] != evacuatedY) || - !(t.ReflexiveKey() || t.Key.Equal(k, k)) { + if it.clearSeq == h.clearSeq && + ((b.tophash[offi] != evacuatedX && b.tophash[offi] != evacuatedY) || + !(t.ReflexiveKey() || t.Key.Equal(k, k))) { // This is the golden data, we can return it. // OR // key!=key, so the entry can't be deleted or updated, so we can just return it. @@ -1079,28 +1083,12 @@ func mapclear(t *maptype, h *hmap) { } h.flags ^= hashWriting - - // Mark buckets empty, so existing iterators can be terminated, see issue #59411. - markBucketsEmpty := func(bucket unsafe.Pointer, mask uintptr) { - for i := uintptr(0); i <= mask; i++ { - b := (*bmap)(add(bucket, i*uintptr(t.BucketSize))) - for ; b != nil; b = b.overflow(t) { - for i := uintptr(0); i < abi.OldMapBucketCount; i++ { - b.tophash[i] = emptyRest - } - } - } - } - markBucketsEmpty(h.buckets, bucketMask(h.B)) - if oldBuckets := h.oldbuckets; oldBuckets != nil { - markBucketsEmpty(oldBuckets, h.oldbucketmask()) - } - h.flags &^= sameSizeGrow h.oldbuckets = nil h.nevacuate = 0 h.noverflow = 0 h.count = 0 + h.clearSeq++ // Reset the hash seed to make it more difficult for attackers to // repeatedly trigger hash collisions. See issue 25237. diff --git a/src/runtime/map_noswiss_test.go b/src/runtime/map_noswiss_test.go index bda448471c..5af7b7b8c8 100644 --- a/src/runtime/map_noswiss_test.go +++ b/src/runtime/map_noswiss_test.go @@ -17,8 +17,8 @@ import ( func TestHmapSize(t *testing.T) { // The structure of hmap is defined in runtime/map.go // and in cmd/compile/internal/reflectdata/map.go and must be in sync. - // The size of hmap should be 48 bytes on 64 bit and 28 bytes on 32 bit platforms. - var hmapSize = uintptr(8 + 5*goarch.PtrSize) + // The size of hmap should be 56 bytes on 64 bit and 36 bytes on 32 bit platforms. + var hmapSize = uintptr(2*8 + 5*goarch.PtrSize) if runtime.RuntimeHmapSize != hmapSize { t.Errorf("sizeof(runtime.hmap{})==%d, want %d", runtime.RuntimeHmapSize, hmapSize) } |