sys/targets: arm64: compile with -fno-jump-tables

Prevent the compiler from generating jump tables that may kick in
at random places and break SyzOS execution
(#5565)

Author: ramosian-glider

sys/targets/targets.go

@@ -291,8 +291,11 @@ var List = map[string]map[string]*Target{
 			KernelHeaderArch: "x86",
 		},
 		ARM64: {
-			PtrSize:          8,
-			PageSize:         4 << 10,
+			PtrSize:  8,
+			PageSize: 4 << 10,
+			// Jump tables mess up with SyzOS execution, disable them for now.
+			// See https://github.com/google/syzkaller/issues/5565 for context.
+			CFlags:           []string{"-fno-jump-tables"},
 			Triple:           "aarch64-linux-gnu",
 			KernelArch:       "arm64",
 			KernelHeaderArch: "arm64",