5 files changed, 19 insertions, 2 deletions
diff --git a/src/cmd/link/internal/ld/data.go b/src/cmd/link/internal/ld/data.go
index bf2bac18af..773efb421f 100644
--- a/src/cmd/link/internal/ld/data.go
+++ b/src/cmd/link/internal/ld/data.go
@@ -2549,6 +2549,19 @@ func (state *dodataState) dodataSect(ctxt *Link, symn sym.SymKind, syms []loader
 			su.SetUint(ctxt.Arch, ctxt.moduledataItabOffset, uint64(typeSize))
 		}
 
+		itabSize := int64(0)
+		for ; i < len(sl); i++ {
+			itabSize = Rnd(itabSize, int64(symalign(ldr, sl[i].sym)))
+			itabSize += sl[i].sz
+		}
+
+		if ctxt.moduledataItabSizeOffset == 0 {
+			Errorf("internal error: phase error: moduledataItabSizeOffset not set in dodataSect")
+		} else {
+			su := ldr.MakeSymbolUpdater(ctxt.Moduledata)
+			su.SetUint(ctxt.Arch, ctxt.moduledataItabSizeOffset, uint64(itabSize))
+		}
+
 	default:
 		sort.Slice(sl, sortFn)
 	}
diff --git a/src/cmd/link/internal/ld/link.go b/src/cmd/link/internal/ld/link.go
index 1ab54dc918..c0d20680a7 100644
--- a/src/cmd/link/internal/ld/link.go
+++ b/src/cmd/link/internal/ld/link.go
@@ -98,6 +98,7 @@ type Link struct {
 
 	moduledataTypeDescOffset int64
 	moduledataItabOffset     int64
+	moduledataItabSizeOffset int64
 
 	PackageFile  map[string]string
 	PackageShlib map[string]string
diff --git a/src/cmd/link/internal/ld/symtab.go b/src/cmd/link/internal/ld/symtab.go
index ddc2278593..37ab0fa582 100644
--- a/src/cmd/link/internal/ld/symtab.go
+++ b/src/cmd/link/internal/ld/symtab.go
@@ -638,6 +638,8 @@ func (ctxt *Link) symtab(pcln *pclntab) []sym.SymKind {
 	moduledata.AddAddr(ctxt.Arch, ldr.Lookup("runtime.etypes", 0))
 	ctxt.moduledataItabOffset = moduledata.Size()
 	moduledata.AddUint(ctxt.Arch, 0) // filled in by dodataSect
+	ctxt.moduledataItabSizeOffset = moduledata.Size()
+	moduledata.AddUint(ctxt.Arch, 0) // filled in by dodataSect
 	moduledata.AddAddr(ctxt.Arch, ldr.Lookup("runtime.rodata", 0))
 	moduledata.AddAddr(ctxt.Arch, ldr.Lookup("go:func.*", 0))
 	moduledata.AddAddr(ctxt.Arch, ldr.Lookup("runtime.epclntab", 0))
diff --git a/src/runtime/iface.go b/src/runtime/iface.go
index 5e58db6108..009f104327 100644
--- a/src/runtime/iface.go
+++ b/src/runtime/iface.go
@@ -269,7 +269,8 @@ func itabsinit() {
 // This is an optimization to let us skip creating itabs we already have.
 func addModuleItabs(md *moduledata) {
 	p := md.types + md.itaboffset
-	for p < md.etypes {
+	end := p + md.itabsize
+	for p < end {
 		itab := (*itab)(unsafe.Pointer(p))
 		itabAdd(itab)
 		p += uintptr(itab.Size())
diff --git a/src/runtime/symtab.go b/src/runtime/symtab.go
index f5e69c26ec..aa84a6f94e 100644
--- a/src/runtime/symtab.go
+++ b/src/runtime/symtab.go
@@ -420,7 +420,7 @@ type moduledata struct {
 	covctrs, ecovctrs          uintptr
 	end, gcdata, gcbss         uintptr
 	types, typedesclen, etypes uintptr
-	itaboffset                 uintptr
+	itaboffset, itabsize       uintptr
 	rodata                     uintptr
 	gofunc                     uintptr // go.func.*
 	epclntab                   uintptr