Fix strace logging for AF_UNIX sockets.

This was broken in commit 64268c8, which moved parsing of addresses for
AF_UNIX sockets to the socket/unix package.

While we're here, add strace support for AF_PACKET sockets, since
socket.AddressAndFamily can already decode their address.

PiperOrigin-RevId: 661391690

pkg/sentry/socket/socket.go

@@ -516,8 +516,8 @@ func BytesToIPAddress(addr []byte) tcpip.Address {
 }
 
 // AddressAndFamily reads an sockaddr struct from the given address and
-// converts it to the FullAddress format. It supports AF_UNIX, AF_INET,
-// AF_INET6, and AF_PACKET addresses.
+// converts it to the FullAddress format. It supports AF_INET, AF_INET6, and
+// AF_PACKET addresses.
 //
 // AddressAndFamily returns an address and its family.
 func AddressAndFamily(addr []byte) (tcpip.FullAddress, uint16, *syserr.Error) {

pkg/sentry/socket/unix/unix.go

@@ -445,7 +445,7 @@ func (s *Socket) Endpoint() transport.Endpoint {
 
 // extractPath extracts and validates the address.
 func extractPath(sockaddr []byte) (string, *syserr.Error) {
-	addr, family, err := addressAndFamily(sockaddr)
+	addr, family, err := AddressAndFamily(sockaddr)
 	if err != nil {
 		if err == syserr.ErrAddressFamilyNotSupported {
 			err = syserr.ErrInvalidArgument
@@ -466,7 +466,9 @@ func extractPath(sockaddr []byte) (string, *syserr.Error) {
 	return p, nil
 }
 
-func addressAndFamily(addr []byte) (transport.Address, uint16, *syserr.Error) {
+// AddressAndFamily converts the addr byte slice to a transport.Address and
+// family. It supports only AF_UNIX addresses.
+func AddressAndFamily(addr []byte) (transport.Address, uint16, *syserr.Error) {
 	// Make sure we have at least 2 bytes for the address family.
 	if len(addr) < 2 {
 		return transport.Address{}, 0, syserr.ErrInvalidArgument

pkg/sentry/strace/BUILD

@@ -39,6 +39,7 @@ go_library(
         "//pkg/sentry/kernel",
         "//pkg/sentry/socket",
         "//pkg/sentry/socket/netlink",
+        "//pkg/sentry/socket/unix",
         "//pkg/sentry/syscalls/linux",
     ],
 )

pkg/sentry/strace/socket.go

@@ -26,6 +26,7 @@ import (
 	"gvisor.dev/gvisor/pkg/sentry/kernel"
 	"gvisor.dev/gvisor/pkg/sentry/socket"
 	"gvisor.dev/gvisor/pkg/sentry/socket/netlink"
+	"gvisor.dev/gvisor/pkg/sentry/socket/unix"
 	slinux "gvisor.dev/gvisor/pkg/sentry/syscalls/linux"
 )
 
@@ -345,17 +346,18 @@ func sockAddr(t *kernel.Task, addr hostarch.Addr, length uint32) string {
 	familyStr := SocketFamily.Parse(uint64(family))
 
 	switch family {
-	case linux.AF_INET, linux.AF_INET6, linux.AF_UNIX:
+	case linux.AF_INET, linux.AF_INET6, linux.AF_PACKET:
 		fa, _, err := socket.AddressAndFamily(b)
 		if err != nil {
 			return fmt.Sprintf("%#x {Family: %s, error extracting address: %v}", addr, familyStr, err)
 		}
-
-		if family == linux.AF_UNIX {
-			return fmt.Sprintf("%#x {Family: %s, Addr: %q}", addr, familyStr, string(fa.Addr.AsSlice()))
-		}
-
 		return fmt.Sprintf("%#x {Family: %s, Addr: %v, Port: %d}", addr, familyStr, fa.Addr, fa.Port)
+	case linux.AF_UNIX:
+		fa, _, err := unix.AddressAndFamily(b)
+		if err != nil {
+			return fmt.Sprintf("%#x {Family: %s, error extracting address: %v}", addr, familyStr, err)
+		}
+		return fmt.Sprintf("%#x {Family: %s, Addr: %q}", addr, familyStr, fa.Addr)
 	case linux.AF_NETLINK:
 		sa, err := netlink.ExtractSockAddr(b)
 		if err != nil {