Changeset 70403 in vbox for trunk/src/bldprogs

Timestamp:

Jan 1, 2018 3:30:04 PM (7 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

120008

Message:

Additions,ValidationKit,VBoxPeSetVersion: Force linker to split .bss out from the .data section as NT 3.1 cannot deal with that (it doesn't check the Misc.VirtualSize field and maps raw bytes up to the next section). We tell the linker .bss is uncached, and have VBoxPeSetImage undo this change.

File:

• trunk/src/bldprogs/VBoxPeSetVersion.cpp (modified) (2 diffs)

trunk/src/bldprogs/VBoxPeSetVersion.cpp

@@ -141 +141 @@
 
     /*
-     * Make the IAT writable for NT 3.1.
+     * Make the IAT writable for NT 3.1 and drop the non-cachable flag from .bss.
+     *
+     * The latter is a trick we use to prevent the linker from merging .data and .bss,
+     * because NT 3.1 does not honor Misc.VirtualSize and won't zero padd the .bss part
+     * if it's not zero padded in the file.  This seemed simpler than adding zero padding.
      */
     if (   uNtVersion <= MK_VER(3, 10)
-        && NtHdrsNew.FileHeader.NumberOfSections > 0
-        && NtHdrsNew.OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IAT].Size > 0)
+        && NtHdrsNew.FileHeader.NumberOfSections > 0)
     {
         uint32_t              cbShdrs = sizeof(IMAGE_SECTION_HEADER) * NtHdrsNew.FileHeader.NumberOfSections;
@@ -161 +164 @@
             return Error("Failed to read section headers at %#lx: %s", offShdrs, strerror(errno));
 
-        uint32_t const uRvaIat = NtHdrsNew.OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IAT].VirtualAddress;
-        uint32_t       uRvaEnd = NtHdrsNew.OptionalHeader.SizeOfImage;
-        uint32_t       i       = NtHdrsNew.FileHeader.NumberOfSections;
+        bool     fFoundBss = false;
+        uint32_t uRvaEnd   = NtHdrsNew.OptionalHeader.SizeOfImage;
+        uint32_t uRvaIat   = NtHdrsNew.OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IAT].Size > 0
+                           ? NtHdrsNew.OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_IAT].VirtualAddress : UINT32_MAX;
+        uint32_t i         = NtHdrsNew.FileHeader.NumberOfSections;
         while (i-- > 0)
             if (!(paShdrs[i].Characteristics & IMAGE_SCN_TYPE_NOLOAD))
             {
-                uint32_t uRva = paShdrs[i].VirtualAddress;
-                if (uRvaIat >= uRva && uRvaIat < uRvaEnd)
+                bool     fModified = false;
+                if (uRvaIat >= paShdrs[i].VirtualAddress && uRvaIat < uRvaEnd)
                 {
                     if (!(paShdrs[i].Characteristics & IMAGE_SCN_MEM_WRITE))
                     {
                         paShdrs[i].Characteristics |= IMAGE_SCN_MEM_WRITE;
-                        unsigned long offShdr = offShdrs + i * sizeof(IMAGE_SECTION_HEADER);
-                        if (fseek(pFile, offShdr, SEEK_SET) != 0)
-                            return Error("Failed to seek to section header #%u at %#lx: %s", i, offShdr, strerror(errno));
-                        if (fwrite(&paShdrs[i], sizeof(IMAGE_SECTION_HEADER), 1, pFile) != 1)
-                            return Error("Failed to write IAT section header header at %#lx: %s", offShdr, strerror(errno));
+                        fModified = true;
                     }
-                    break;
-                }
-                uRvaEnd = uRva;
+                    uRvaIat = UINT32_MAX;
+                }
+
+                if (   !fFoundBss
+                    && strcmp((const char *)paShdrs[i].Name, ".bss") == 0)
+                {
+                    if (paShdrs[i].Characteristics & IMAGE_SCN_MEM_NOT_CACHED)
+                    {
+                        paShdrs[i].Characteristics &= ~IMAGE_SCN_MEM_NOT_CACHED;
+                        fModified = true;
+                    }
+                    fFoundBss = true;
+                }
+
+                if (fModified)
+                {
+                    unsigned long offShdr = offShdrs + i * sizeof(IMAGE_SECTION_HEADER);
+                    if (fseek(pFile, offShdr, SEEK_SET) != 0)
+                        return Error("Failed to seek to section header #%u at %#lx: %s", i, offShdr, strerror(errno));
+                    if (fwrite(&paShdrs[i], sizeof(IMAGE_SECTION_HEADER), 1, pFile) != 1)
+                        return Error("Failed to write %8.8s section header header at %#lx: %s",
+                                     paShdrs[i].Name, offShdr, strerror(errno));
+                    if (uRvaIat == UINT32_MAX && fFoundBss)
+                        break;
+                }
+
+                /* Advance */
+                uRvaEnd = paShdrs[i].VirtualAddress;
             }