Merge pull request #6142 from lat9nq/prog_meta_ref_bind_address

program_metadata: Avoid reference binding to misaligned address

2 files changed, 51 insertions, 15 deletions

diff --git a/src/core/file_sys/program_metadata.cpp b/src/core/file_sys/program_metadata.cpp
index e0cdf3520..08d489eab 100644
--- a/src/core/file_sys/program_metadata.cpp
+++ b/src/core/file_sys/program_metadata.cpp
@@ -33,11 +33,55 @@ Loader::ResultStatus ProgramMetadata::Load(VirtualFile file) {
         return Loader::ResultStatus::ErrorBadACIHeader;
     }
 
-    if (sizeof(FileAccessControl) != file->ReadObject(&acid_file_access, acid_header.fac_offset)) {
+    // Load acid_file_access per-component instead of the entire struct, since this struct does not
+    // reflect the layout of the real data.
+    std::size_t current_offset = acid_header.fac_offset;
+    if (sizeof(FileAccessControl::version) != file->ReadBytes(&acid_file_access.version,
+                                                              sizeof(FileAccessControl::version),
+                                                              current_offset)) {
+        return Loader::ResultStatus::ErrorBadFileAccessControl;
+    }
+    if (sizeof(FileAccessControl::permissions) !=
+        file->ReadBytes(&acid_file_access.permissions, sizeof(FileAccessControl::permissions),
+                        current_offset += sizeof(FileAccessControl::version) + 3)) {
+        return Loader::ResultStatus::ErrorBadFileAccessControl;
+    }
+    if (sizeof(FileAccessControl::unknown) !=
+        file->ReadBytes(&acid_file_access.unknown, sizeof(FileAccessControl::unknown),
+                        current_offset + sizeof(FileAccessControl::permissions))) {
         return Loader::ResultStatus::ErrorBadFileAccessControl;
     }
 
-    if (sizeof(FileAccessHeader) != file->ReadObject(&aci_file_access, aci_header.fah_offset)) {
+    // Load aci_file_access per-component instead of the entire struct, same as acid_file_access
+    current_offset = aci_header.fah_offset;
+    if (sizeof(FileAccessHeader::version) != file->ReadBytes(&aci_file_access.version,
+                                                             sizeof(FileAccessHeader::version),
+                                                             current_offset)) {
+        return Loader::ResultStatus::ErrorBadFileAccessHeader;
+    }
+    if (sizeof(FileAccessHeader::permissions) !=
+        file->ReadBytes(&aci_file_access.permissions, sizeof(FileAccessHeader::permissions),
+                        current_offset += sizeof(FileAccessHeader::version) + 3)) {
+        return Loader::ResultStatus::ErrorBadFileAccessHeader;
+    }
+    if (sizeof(FileAccessHeader::unk_offset) !=
+        file->ReadBytes(&aci_file_access.unk_offset, sizeof(FileAccessHeader::unk_offset),
+                        current_offset += sizeof(FileAccessHeader::permissions))) {
+        return Loader::ResultStatus::ErrorBadFileAccessHeader;
+    }
+    if (sizeof(FileAccessHeader::unk_size) !=
+        file->ReadBytes(&aci_file_access.unk_size, sizeof(FileAccessHeader::unk_size),
+                        current_offset += sizeof(FileAccessHeader::unk_offset))) {
+        return Loader::ResultStatus::ErrorBadFileAccessHeader;
+    }
+    if (sizeof(FileAccessHeader::unk_offset_2) !=
+        file->ReadBytes(&aci_file_access.unk_offset_2, sizeof(FileAccessHeader::unk_offset_2),
+                        current_offset += sizeof(FileAccessHeader::unk_size))) {
+        return Loader::ResultStatus::ErrorBadFileAccessHeader;
+    }
+    if (sizeof(FileAccessHeader::unk_size_2) !=
+        file->ReadBytes(&aci_file_access.unk_size_2, sizeof(FileAccessHeader::unk_size_2),
+                        current_offset + sizeof(FileAccessHeader::unk_offset_2))) {
         return Loader::ResultStatus::ErrorBadFileAccessHeader;
     }
 
@@ -152,9 +196,7 @@ void ProgramMetadata::Print() const {
     LOG_DEBUG(Service_FS, " > Is Retail:           {}", acid_header.is_retail ? "YES" : "NO");
     LOG_DEBUG(Service_FS, "Title ID Min:           0x{:016X}", acid_header.title_id_min);
     LOG_DEBUG(Service_FS, "Title ID Max:           0x{:016X}", acid_header.title_id_max);
-    u64_le permissions_l; // local copy to fix alignment error
-    std::memcpy(&permissions_l, &acid_file_access.permissions, sizeof(permissions_l));
-    LOG_DEBUG(Service_FS, "Filesystem Access:      0x{:016X}\n", permissions_l);
+    LOG_DEBUG(Service_FS, "Filesystem Access:      0x{:016X}\n", acid_file_access.permissions);
 
     // Begin ACI0 printing (actual perms, unsigned)
     LOG_DEBUG(Service_FS, "Magic:                  {:.4}", aci_header.magic.data());
diff --git a/src/core/file_sys/program_metadata.h b/src/core/file_sys/program_metadata.h
index e8fb4e27f..2e8960b07 100644
--- a/src/core/file_sys/program_metadata.h
+++ b/src/core/file_sys/program_metadata.h
@@ -144,20 +144,18 @@ private:
 
     static_assert(sizeof(AciHeader) == 0x40, "ACI0 header structure size is wrong");
 
-#pragma pack(push, 1)
-
+    // FileAccessControl and FileAccessHeader need loaded per-component: this layout does not
+    // reflect the real layout to avoid reference binding to misaligned addresses
     struct FileAccessControl {
         u8 version;
-        INSERT_PADDING_BYTES(3);
+        // 3 padding bytes
         u64_le permissions;
         std::array<u8, 0x20> unknown;
     };
 
-    static_assert(sizeof(FileAccessControl) == 0x2C, "FS access control structure size is wrong");
-
     struct FileAccessHeader {
         u8 version;
-        INSERT_PADDING_BYTES(3);
+        // 3 padding bytes
         u64_le permissions;
         u32_le unk_offset;
         u32_le unk_size;
@@ -165,10 +163,6 @@ private:
         u32_le unk_size_2;
     };
 
-    static_assert(sizeof(FileAccessHeader) == 0x1C, "FS access header structure size is wrong");
-
-#pragma pack(pop)
-
     Header npdm_header;
     AciHeader aci_header;
     AcidHeader acid_header;