Reject EBPF_OP_LDDW if src != 0 (#132)

Signed-off-by: Alan Jowett <alanjo@microsoft.com>
iovisor · Oct 12, 2022 · 09a122b · 09a122b
1 parent 0afd630
commit 09a122b
Show file tree

Hide file tree

Showing 2 changed files with 9 additions and 0 deletions.
diff --git a/tests/err-lddw-invalid-src.data b/tests/err-lddw-invalid-src.data
@@ -0,0 +1,5 @@
+-- raw
+0x5566778800001118
+0x0000000000000000
+-- error
+Failed to load code: invalid source register for LDDW at PC 0
diff --git a/vm/ubpf_vm.c b/vm/ubpf_vm.c
@@ -700,6 +700,10 @@ validate(const struct ubpf_vm *vm, const struct ebpf_inst *insts, uint32_t num_i
             break;
 
         case EBPF_OP_LDDW:
+            if (inst.src != 0) {
+                *errmsg = ubpf_error("invalid source register for LDDW at PC %d", i);
+                return false;
+            }
             if (i + 1 >= num_insts || insts[i+1].opcode != 0) {
                 *errmsg = ubpf_error("incomplete lddw at PC %d", i);
                 return false;