webnet/tailscale
1
0
Fork 0
Code Issues Pull Requests 1 Packages Projects Releases Wiki Activity

cmd/cloner: deep-clone pointer elements in map-of-slice values

Browse Source 
The cloner's codegen for map[K][]*V fields was doing a shallow
append (copying pointer values) instead of cloning each element.
This meant that cloned structs aliased the original's pointed-to
values through the map's slice entries.

Mirror the existing standalone-slice logic that checks
ContainsPointers(sliceType.Elem()) and generates per-element
cloning for pointer, interface, and struct types.

Regenerate net/dns and tailcfg which both had affected
map[...][]*dnstype.Resolver fields.

Fixes #19284

Signed-off-by: Andrew Dunham <andrew@tailscale.com>
This commit is contained in:
Andrew Dunham
2026-04-07 20:52:09 +00:00
committed by Andrew Dunham
parent 47ecbe5845
commit d52ae45e9b
7 changed files with 217 additions and 42 deletions
Download Patch File Download Diff File Expand all files Collapse all files
cmd/viewer/tests/tests_clone.go
+68 -12
View File
@@ -96,14 +96,34 @@ func (src *Map) Clone() *Map {
dst.StructWithoutPtr = maps.Clone(src.StructWithoutPtr)
if dst.SlicesWithPtrs != nil {
dst.SlicesWithPtrs = map[string][]*StructWithPtrs{}
for k := range src.SlicesWithPtrs {
dst.SlicesWithPtrs[k] = append([]*StructWithPtrs{}, src.SlicesWithPtrs[k]...)
for k, sv := range src.SlicesWithPtrs {
if sv == nil {
continue
}
dst.SlicesWithPtrs[k] = make([]*StructWithPtrs, len(sv))
for i := range sv {
if sv[i] == nil {
dst.SlicesWithPtrs[k][i] = nil
} else {
dst.SlicesWithPtrs[k][i] = sv[i].Clone()
}
}
}
}
if dst.SlicesWithoutPtrs != nil {
dst.SlicesWithoutPtrs = map[string][]*StructWithoutPtrs{}
for k := range src.SlicesWithoutPtrs {
dst.SlicesWithoutPtrs[k] = append([]*StructWithoutPtrs{}, src.SlicesWithoutPtrs[k]...)
for k, sv := range src.SlicesWithoutPtrs {
if sv == nil {
continue
}
dst.SlicesWithoutPtrs[k] = make([]*StructWithoutPtrs, len(sv))
for i := range sv {
if sv[i] == nil {
dst.SlicesWithoutPtrs[k][i] = nil
} else {
dst.SlicesWithoutPtrs[k][i] = new(*sv[i])
}
}
}
}
dst.StructWithoutPtrKey = maps.Clone(src.StructWithoutPtrKey)
@@ -115,8 +135,18 @@ func (src *Map) Clone() *Map {
}
if dst.SliceIntPtr != nil {
dst.SliceIntPtr = map[string][]*int{}
for k := range src.SliceIntPtr {
dst.SliceIntPtr[k] = append([]*int{}, src.SliceIntPtr[k]...)
for k, sv := range src.SliceIntPtr {
if sv == nil {
continue
}
dst.SliceIntPtr[k] = make([]*int, len(sv))
for i := range sv {
if sv[i] == nil {
dst.SliceIntPtr[k][i] = nil
} else {
dst.SliceIntPtr[k][i] = new(*sv[i])
}
}
}
}
dst.PointerKey = maps.Clone(src.PointerKey)
@@ -399,8 +429,14 @@ func (src *GenericCloneableStruct[T, V]) Clone() *GenericCloneableStruct[T, V] {
}
if dst.SliceMap != nil {
dst.SliceMap = map[string][]T{}
for k := range src.SliceMap {
dst.SliceMap[k] = append([]T{}, src.SliceMap[k]...)
for k, sv := range src.SliceMap {
if sv == nil {
continue
}
dst.SliceMap[k] = make([]T, len(sv))
for i := range sv {
dst.SliceMap[k][i] = sv[i].Clone()
}
}
}
return dst
@@ -500,14 +536,34 @@ func (src *StructWithTypeAliasFields) Clone() *StructWithTypeAliasFields {
}
if dst.MapOfSlicesWithPtrs != nil {
dst.MapOfSlicesWithPtrs = map[string][]*StructWithPtrsAlias{}
for k := range src.MapOfSlicesWithPtrs {
dst.MapOfSlicesWithPtrs[k] = append([]*StructWithPtrsAlias{}, src.MapOfSlicesWithPtrs[k]...)
for k, sv := range src.MapOfSlicesWithPtrs {
if sv == nil {
continue
}
dst.MapOfSlicesWithPtrs[k] = make([]*StructWithPtrsAlias, len(sv))
for i := range sv {
if sv[i] == nil {
dst.MapOfSlicesWithPtrs[k][i] = nil
} else {
dst.MapOfSlicesWithPtrs[k][i] = sv[i].Clone()
}
}
}
}
if dst.MapOfSlicesWithoutPtrs != nil {
dst.MapOfSlicesWithoutPtrs = map[string][]*StructWithoutPtrsAlias{}
for k := range src.MapOfSlicesWithoutPtrs {
dst.MapOfSlicesWithoutPtrs[k] = append([]*StructWithoutPtrsAlias{}, src.MapOfSlicesWithoutPtrs[k]...)
for k, sv := range src.MapOfSlicesWithoutPtrs {
if sv == nil {
continue
}
dst.MapOfSlicesWithoutPtrs[k] = make([]*StructWithoutPtrsAlias, len(sv))
for i := range sv {
if sv[i] == nil {
dst.MapOfSlicesWithoutPtrs[k][i] = nil
} else {
dst.MapOfSlicesWithoutPtrs[k][i] = new(*sv[i])
}
}
}
}
return dst