Merge pull request #74 from matthewfahrenkrug/check-rsdp-sum

multiboot: Check RSDP checksum

Author: ALSchwalm

Cargo.lock

@@ -8,7 +8,7 @@ license-file = "LICENSE"
 description = "A intel-focused hypervisor using VT-x/EPT"
 
 [dependencies]
-multiboot2 = "0.8.1"
+multiboot2 = "0.9.0"
 mythril_core = { version = "*", path = "../mythril_core" }
 log = { version = "0.4.8", default-features = false }
 linked_list_allocator = "0.8.1"

mythril_multiboot2/Cargo.toml

@@ -1,3 +1,4 @@
+use alloc::string::ToString;
 use multiboot2::BootInformation;
 use mythril_core::acpi;
 use mythril_core::error::{Error, Result};
@@ -41,6 +42,11 @@ impl VmServices for Multiboot2Services {
                 self.info.rsdp_v1_tag().map_or_else(
                     || Err(Error::NotFound),
                     move |tag_v1| {
+                        if !tag_v1.checksum_is_valid() {
+                            return Err(Error::InvalidValue(
+                                "Invalid RSDP V1 checksum".to_string(),
+                            ));
+                        }
                         let id = tag_v1.oem_id().unwrap_or("      ").as_bytes();
                         arr.copy_from_slice(&id[0..6]);
                         Ok(acpi::rsdp::RSDP::V1 {
@@ -51,6 +57,11 @@ impl VmServices for Multiboot2Services {
                 )
             },
             move |tag_v2| {
+                if !tag_v2.checksum_is_valid() {
+                    return Err(Error::InvalidValue(
+                        "Invalid RSDP V2 checksum".to_string(),
+                    ));
+                }
                 let id = tag_v2.oem_id().unwrap_or("      ").as_bytes();
                 let mut arr: [u8; 6] = [0; 6];
                 arr.copy_from_slice(&id[0..6]);