syscall: fix alignment check for link-layer information on BSD variants
When link-layer information is wrapped with sockaddr_dl, we need to
follow the len field of sockaddr_dl. When link-layer information is
naked, we need to use the length of whole link-layer information.
Fixes #12641.
Change-Id: I4d377f64cbab1760b993fc55c719288616042bbb
Reviewed-on: https://go-review.googlesource.com/14939
Reviewed-by: Ian Lance Taylor <iant@golang.org>
diff --git a/src/syscall/route_bsd.go b/src/syscall/route_bsd.go
index c62fdc3..4434a56 100644
--- a/src/syscall/route_bsd.go
+++ b/src/syscall/route_bsd.go
@@ -44,6 +44,9 @@
// parseSockaddrLink parses b as a datalink socket address.
func parseSockaddrLink(b []byte) (*SockaddrDatalink, error) {
+ if len(b) < 8 {
+ return nil, EINVAL
+ }
sa, _, err := parseLinkLayerAddr(b[4:])
if err != nil {
return nil, err
@@ -77,16 +80,16 @@
Slen byte
}
lla := (*linkLayerAddr)(unsafe.Pointer(&b[0]))
- l := rsaAlignOf(int(4 + lla.Nlen + lla.Alen + lla.Slen))
+ l := 4 + int(lla.Nlen) + int(lla.Alen) + int(lla.Slen)
if len(b) < l {
return nil, 0, EINVAL
}
b = b[4:]
sa := &SockaddrDatalink{Type: lla.Type, Nlen: lla.Nlen, Alen: lla.Alen, Slen: lla.Slen}
- for i := 0; len(sa.Data) > i && i < int(lla.Nlen+lla.Alen+lla.Slen); i++ {
+ for i := 0; len(sa.Data) > i && i < l-4; i++ {
sa.Data[i] = int8(b[i])
}
- return sa, l, nil
+ return sa, rsaAlignOf(l), nil
}
// parseSockaddrInet parses b as an internet socket address.
