From ee45334f147c9d5ff75d10c619c9c99ce4ba51ca Mon Sep 17 00:00:00 2001 From: Ayush Ranjan Date: Fri, 16 Apr 2021 17:49:52 -0700 Subject: [lisa] Make go_marshal pass correctly sized buffers to safecopy. gohacks.Memmove() takes in the number of bytes to move. The current generated code passes len(src) and len(dst) as the number of bytes to move. However, the marshal.Marshallable interface allows passing in larger buffers. The stated precondition is that the buffer should be "at least" SizeBytes() in length but it is allowed to be larger. This change now correctly calls Memmove with the argument for the number of bytes to move as type.SizeBytes(). This was caught when I made lisafs use the Unsafe marshalling API and got a lot of memory violations. PiperOrigin-RevId: 368952642 --- tools/go_marshal/gomarshal/generator_interfaces_array_newtype.go | 4 ++-- .../gomarshal/generator_interfaces_primitive_newtype.go | 4 ++-- tools/go_marshal/gomarshal/generator_interfaces_struct.go | 8 ++++---- 3 files changed, 8 insertions(+), 8 deletions(-) diff --git a/tools/go_marshal/gomarshal/generator_interfaces_array_newtype.go b/tools/go_marshal/gomarshal/generator_interfaces_array_newtype.go index e8ce6e366..bd7741ae5 100644 --- a/tools/go_marshal/gomarshal/generator_interfaces_array_newtype.go +++ b/tools/go_marshal/gomarshal/generator_interfaces_array_newtype.go @@ -89,14 +89,14 @@ func (g *interfaceGenerator) emitMarshallableForArrayNewtype(n *ast.Ident, a *as g.emit("// MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.\n") g.emit("func (%s *%s) MarshalUnsafe(dst []byte) {\n", g.r, g.typeName()) g.inIndent(func() { - g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(&%s[0]), uintptr(len(dst)))\n", g.r) + g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(&%s[0]), uintptr(%s.SizeBytes()))\n", g.r, g.r) }) g.emit("}\n\n") g.emit("// UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.\n") g.emit("func (%s *%s) UnmarshalUnsafe(src []byte) {\n", g.r, g.typeName()) g.inIndent(func() { - g.emit("gohacks.Memmove(unsafe.Pointer(%s), unsafe.Pointer(&src[0]), uintptr(len(src)))\n", g.r) + g.emit("gohacks.Memmove(unsafe.Pointer(%s), unsafe.Pointer(&src[0]), uintptr(%s.SizeBytes()))\n", g.r, g.r) }) g.emit("}\n\n") diff --git a/tools/go_marshal/gomarshal/generator_interfaces_primitive_newtype.go b/tools/go_marshal/gomarshal/generator_interfaces_primitive_newtype.go index 19aa5994a..ba4b7324e 100644 --- a/tools/go_marshal/gomarshal/generator_interfaces_primitive_newtype.go +++ b/tools/go_marshal/gomarshal/generator_interfaces_primitive_newtype.go @@ -141,14 +141,14 @@ func (g *interfaceGenerator) emitMarshallableForPrimitiveNewtype(nt *ast.Ident) g.emit("// MarshalUnsafe implements marshal.Marshallable.MarshalUnsafe.\n") g.emit("func (%s *%s) MarshalUnsafe(dst []byte) {\n", g.r, g.typeName()) g.inIndent(func() { - g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(%s), uintptr(len(dst)))\n", g.r) + g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(%s), uintptr(%s.SizeBytes()))\n", g.r, g.r) }) g.emit("}\n\n") g.emit("// UnmarshalUnsafe implements marshal.Marshallable.UnmarshalUnsafe.\n") g.emit("func (%s *%s) UnmarshalUnsafe(src []byte) {\n", g.r, g.typeName()) g.inIndent(func() { - g.emit("gohacks.Memmove(unsafe.Pointer(%s), unsafe.Pointer(&src[0]), uintptr(len(src)))\n", g.r) + g.emit("gohacks.Memmove(unsafe.Pointer(%s), unsafe.Pointer(&src[0]), uintptr(%s.SizeBytes()))\n", g.r, g.r) }) g.emit("}\n\n") diff --git a/tools/go_marshal/gomarshal/generator_interfaces_struct.go b/tools/go_marshal/gomarshal/generator_interfaces_struct.go index 087c88b54..4c47218f1 100644 --- a/tools/go_marshal/gomarshal/generator_interfaces_struct.go +++ b/tools/go_marshal/gomarshal/generator_interfaces_struct.go @@ -275,13 +275,13 @@ func (g *interfaceGenerator) emitMarshallableForStruct(st *ast.StructType) { if cond, ok := g.areFieldsPackedExpression(); ok { g.emit("if %s {\n", cond) g.inIndent(func() { - g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(%s), uintptr(len(dst)))\n", g.r) + g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(%s), uintptr(%s.SizeBytes()))\n", g.r, g.r) }) g.emit("} else {\n") g.inIndent(fallback) g.emit("}\n") } else { - g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(%s), uintptr(len(dst)))\n", g.r) + g.emit("gohacks.Memmove(unsafe.Pointer(&dst[0]), unsafe.Pointer(%s), uintptr(%s.SizeBytes()))\n", g.r, g.r) } } else { fallback() @@ -301,13 +301,13 @@ func (g *interfaceGenerator) emitMarshallableForStruct(st *ast.StructType) { if cond, ok := g.areFieldsPackedExpression(); ok { g.emit("if %s {\n", cond) g.inIndent(func() { - g.emit("gohacks.Memmove(unsafe.Pointer(%s), unsafe.Pointer(&src[0]), uintptr(len(src)))\n", g.r) + g.emit("gohacks.Memmove(unsafe.Pointer(%s), unsafe.Pointer(&src[0]), uintptr(%s.SizeBytes()))\n", g.r, g.r) }) g.emit("} else {\n") g.inIndent(fallback) g.emit("}\n") } else { - g.emit("gohacks.Memmove(unsafe.Pointer(%s), unsafe.Pointer(&src[0]), uintptr(len(src)))\n", g.r) + g.emit("gohacks.Memmove(unsafe.Pointer(%s), unsafe.Pointer(&src[0]), uintptr(%s.SizeBytes()))\n", g.r, g.r) } } else { fallback() -- cgit v1.2.3