Mark [r1,r5] as invalid after a call

Signed-off-by: Alan Jowett <alan.jowett@microsoft.com>
iovisor · May 7, 2024 · f7016ab · f7016ab
1 parent 621d21f
commit f7016ab
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/vm/ubpf_vm.c b/vm/ubpf_vm.c
@@ -542,6 +542,8 @@ ubpf_validate_shadow_register(const struct ubpf_vm* vm, uint16_t* shadow_registe
     if (inst.opcode == EBPF_OP_CALL) {
         // Mark the return address register as initialized.
         *shadow_registers |= 1 << 0;
+        // Mark r1-r5 as uninitialized.
+        *shadow_registers &= ~0x3e;
     }
 
     if (inst.opcode == EBPF_OP_EXIT && !(*shadow_registers & (1 << 0))) {