sql: fix potential corruption in QueryRow.Scan into a *[]byte
Fixes #2622
R=golang-dev, adg
CC=golang-dev
https://golang.org/cl/5533077
diff --git a/src/pkg/exp/sql/fakedb_test.go b/src/pkg/exp/sql/fakedb_test.go
index 0883dd9..0a1dd09 100644
--- a/src/pkg/exp/sql/fakedb_test.go
+++ b/src/pkg/exp/sql/fakedb_test.go
@@ -306,6 +306,8 @@
switch ctype {
case "string":
subsetVal = []byte(value)
+ case "blob":
+ subsetVal = []byte(value)
case "int32":
i, err := strconv.Atoi(value)
if err != nil {
@@ -510,9 +512,19 @@
pos int
rows []*row
closed bool
+
+ // a clone of slices to give out to clients, indexed by the
+ // the original slice's first byte address. we clone them
+ // just so we're able to corrupt them on close.
+ bytesClone map[*byte][]byte
}
func (rc *rowsCursor) Close() error {
+ if !rc.closed {
+ for _, bs := range rc.bytesClone {
+ bs[0] = 255 // first byte corrupted
+ }
+ }
rc.closed = true
return nil
}
@@ -537,6 +549,19 @@
// for ease of drivers, and to prevent drivers from
// messing up conversions or doing them differently.
dest[i] = v
+
+ if bs, ok := v.([]byte); ok {
+ if rc.bytesClone == nil {
+ rc.bytesClone = make(map[*byte][]byte)
+ }
+ clone, ok := rc.bytesClone[&bs[0]]
+ if !ok {
+ clone = make([]byte, len(bs))
+ copy(clone, bs)
+ rc.bytesClone[&bs[0]] = clone
+ }
+ dest[i] = clone
+ }
}
return nil
}
