X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=blobdiff_plain;f=BaseTools%2FSource%2FC%2FGenFw%2FElf64Convert.c;h=15da89c755fe755f6edbb92ec9f7be9172d85113;hp=c39bdff063ab4cecbd6bb49c16fe32a22e9b5de6;hb=c6a14de3ef30291918f3b15436cf6a75db413eea;hpb=60e85a39fe49071683f3ac5e208f1582511d26bf
diff --git a/BaseTools/Source/C/GenFw/Elf64Convert.c b/BaseTools/Source/C/GenFw/Elf64Convert.c
index c39bdff063..15da89c755 100644
--- a/BaseTools/Source/C/GenFw/Elf64Convert.c
+++ b/BaseTools/Source/C/GenFw/Elf64Convert.c
@@ -1,7 +1,7 @@
/** @file
Elf64 convert solution
-Copyright (c) 2010 - 2017, Intel Corporation. All rights reserved.
+Copyright (c) 2010 - 2018, Intel Corporation. All rights reserved.
Portions copyright (c) 2013-2014, ARM Ltd. All rights reserved.
This program and the accompanying materials are licensed and made available
@@ -94,6 +94,15 @@ STATIC Elf_Ehdr *mEhdr;
STATIC Elf_Shdr *mShdrBase;
STATIC Elf_Phdr *mPhdrBase;
+//
+// GOT information
+//
+STATIC Elf_Shdr *mGOTShdr = NULL;
+STATIC UINT32 mGOTShindex = 0;
+STATIC UINT32 *mGOTCoffEntries = NULL;
+STATIC UINT32 mGOTMaxCoffEntries = 0;
+STATIC UINT32 mGOTNumCoffEntries = 0;
+
//
// Coff information
//
@@ -322,6 +331,134 @@ GetSymName (
return StrtabContents + Sym->st_name;
}
+//
+// Find the ELF section hosting the GOT from an ELF Rva
+// of a single GOT entry. Normally, GOT is placed in
+// ELF .text section, so assume once we find in which
+// section the GOT is, all GOT entries are there, and
+// just verify this.
+//
+STATIC
+VOID
+FindElfGOTSectionFromGOTEntryElfRva (
+ Elf64_Addr GOTEntryElfRva
+ )
+{
+ UINT32 i;
+ if (mGOTShdr != NULL) {
+ if (GOTEntryElfRva >= mGOTShdr->sh_addr &&
+ GOTEntryElfRva < mGOTShdr->sh_addr + mGOTShdr->sh_size) {
+ return;
+ }
+ Error (NULL, 0, 3000, "Unsupported", "FindElfGOTSectionFromGOTEntryElfRva: GOT entries found in multiple sections.");
+ exit(EXIT_FAILURE);
+ }
+ for (i = 0; i < mEhdr->e_shnum; i++) {
+ Elf_Shdr *shdr = GetShdrByIndex(i);
+ if (GOTEntryElfRva >= shdr->sh_addr &&
+ GOTEntryElfRva < shdr->sh_addr + shdr->sh_size) {
+ mGOTShdr = shdr;
+ mGOTShindex = i;
+ return;
+ }
+ }
+ Error (NULL, 0, 3000, "Invalid", "FindElfGOTSectionFromGOTEntryElfRva: ElfRva 0x%016LX for GOT entry not found in any section.", GOTEntryElfRva);
+ exit(EXIT_FAILURE);
+}
+
+//
+// Stores locations of GOT entries in COFF image.
+// Returns TRUE if GOT entry is new.
+// Simple implementation as number of GOT
+// entries is expected to be low.
+//
+
+STATIC
+BOOLEAN
+AccumulateCoffGOTEntries (
+ UINT32 GOTCoffEntry
+ )
+{
+ UINT32 i;
+ if (mGOTCoffEntries != NULL) {
+ for (i = 0; i < mGOTNumCoffEntries; i++) {
+ if (mGOTCoffEntries[i] == GOTCoffEntry) {
+ return FALSE;
+ }
+ }
+ }
+ if (mGOTCoffEntries == NULL) {
+ mGOTCoffEntries = (UINT32*)malloc(5 * sizeof *mGOTCoffEntries);
+ if (mGOTCoffEntries == NULL) {
+ Error (NULL, 0, 4001, "Resource", "memory cannot be allocated!");
+ }
+ assert (mGOTCoffEntries != NULL);
+ mGOTMaxCoffEntries = 5;
+ mGOTNumCoffEntries = 0;
+ } else if (mGOTNumCoffEntries == mGOTMaxCoffEntries) {
+ mGOTCoffEntries = (UINT32*)realloc(mGOTCoffEntries, 2 * mGOTMaxCoffEntries * sizeof *mGOTCoffEntries);
+ if (mGOTCoffEntries == NULL) {
+ Error (NULL, 0, 4001, "Resource", "memory cannot be allocated!");
+ }
+ assert (mGOTCoffEntries != NULL);
+ mGOTMaxCoffEntries += mGOTMaxCoffEntries;
+ }
+ mGOTCoffEntries[mGOTNumCoffEntries++] = GOTCoffEntry;
+ return TRUE;
+}
+
+//
+// 32-bit Unsigned integer comparator for qsort.
+//
+STATIC
+int
+UINT32Comparator (
+ const void* lhs,
+ const void* rhs
+ )
+{
+ if (*(const UINT32*)lhs < *(const UINT32*)rhs) {
+ return -1;
+ }
+ return *(const UINT32*)lhs > *(const UINT32*)rhs;
+}
+
+//
+// Emit accumulated Coff GOT entry relocations into
+// Coff image. This function performs its job
+// once and then releases the entry list, so
+// it can safely be called multiple times.
+//
+STATIC
+VOID
+EmitGOTRelocations (
+ VOID
+ )
+{
+ UINT32 i;
+ if (mGOTCoffEntries == NULL) {
+ return;
+ }
+ //
+ // Emit Coff relocations with Rvas ordered.
+ //
+ qsort(
+ mGOTCoffEntries,
+ mGOTNumCoffEntries,
+ sizeof *mGOTCoffEntries,
+ UINT32Comparator);
+ for (i = 0; i < mGOTNumCoffEntries; i++) {
+ VerboseMsg ("EFI_IMAGE_REL_BASED_DIR64 Offset: 0x%08X", mGOTCoffEntries[i]);
+ CoffAddFixup(
+ mGOTCoffEntries[i],
+ EFI_IMAGE_REL_BASED_DIR64);
+ }
+ free(mGOTCoffEntries);
+ mGOTCoffEntries = NULL;
+ mGOTMaxCoffEntries = 0;
+ mGOTNumCoffEntries = 0;
+}
+
//
// Elf functions interface implementation
//
@@ -376,6 +513,15 @@ ScanSections64 (
}
}
+ //
+ // Check if mCoffAlignment is larger than MAX_COFF_ALIGNMENT
+ //
+ if (mCoffAlignment > MAX_COFF_ALIGNMENT) {
+ Error (NULL, 0, 3000, "Invalid", "Section alignment is larger than MAX_COFF_ALIGNMENT.");
+ assert (FALSE);
+ }
+
+
//
// Move the PE/COFF header right before the first section. This will help us
// save space when converting to TE.
@@ -634,6 +780,7 @@ WriteSections64 (
Elf_Shdr *SecShdr;
UINT32 SecOffset;
BOOLEAN (*Filter)(Elf_Shdr *);
+ Elf64_Addr GOTEntryRva;
//
// Initialize filter pointer
@@ -661,6 +808,9 @@ WriteSections64 (
switch (Shdr->sh_type) {
case SHT_PROGBITS:
/* Copy. */
+ if (Shdr->sh_offset + Shdr->sh_size > mFileBufferSize) {
+ return FALSE;
+ }
memcpy(mCoffFile + mCoffSectionsOffset[Idx],
(UINT8*)mEhdr + Shdr->sh_offset,
(size_t) Shdr->sh_size);
@@ -698,7 +848,7 @@ WriteSections64 (
// section that applies to the entire binary, and which will have its section
// index set to #0 (which is a NULL section with the SHF_ALLOC bit cleared).
//
- // In the absence of GOT based relocations (which we currently don't support),
+ // In the absence of GOT based relocations,
// this RELA section will contain redundant R_xxx_RELATIVE relocations, one
// for every R_xxx_xx64 relocation appearing in the per-section RELA sections.
// (i.e., .rela.text and .rela.data)
@@ -788,24 +938,24 @@ WriteSections64 (
// Absolute relocation.
//
VerboseMsg ("R_X86_64_64");
- VerboseMsg ("Offset: 0x%08X, Addend: 0x%016LX",
- (UINT32)(SecOffset + (Rel->r_offset - SecShdr->sh_addr)),
+ VerboseMsg ("Offset: 0x%08X, Addend: 0x%016LX",
+ (UINT32)(SecOffset + (Rel->r_offset - SecShdr->sh_addr)),
*(UINT64 *)Targ);
*(UINT64 *)Targ = *(UINT64 *)Targ - SymShdr->sh_addr + mCoffSectionsOffset[Sym->st_shndx];
VerboseMsg ("Relocation: 0x%016LX", *(UINT64*)Targ);
break;
case R_X86_64_32:
VerboseMsg ("R_X86_64_32");
- VerboseMsg ("Offset: 0x%08X, Addend: 0x%08X",
- (UINT32)(SecOffset + (Rel->r_offset - SecShdr->sh_addr)),
+ VerboseMsg ("Offset: 0x%08X, Addend: 0x%08X",
+ (UINT32)(SecOffset + (Rel->r_offset - SecShdr->sh_addr)),
*(UINT32 *)Targ);
*(UINT32 *)Targ = (UINT32)((UINT64)(*(UINT32 *)Targ) - SymShdr->sh_addr + mCoffSectionsOffset[Sym->st_shndx]);
VerboseMsg ("Relocation: 0x%08X", *(UINT32*)Targ);
break;
case R_X86_64_32S:
VerboseMsg ("R_X86_64_32S");
- VerboseMsg ("Offset: 0x%08X, Addend: 0x%08X",
- (UINT32)(SecOffset + (Rel->r_offset - SecShdr->sh_addr)),
+ VerboseMsg ("Offset: 0x%08X, Addend: 0x%08X",
+ (UINT32)(SecOffset + (Rel->r_offset - SecShdr->sh_addr)),
*(UINT32 *)Targ);
*(INT32 *)Targ = (INT32)((INT64)(*(INT32 *)Targ) - SymShdr->sh_addr + mCoffSectionsOffset[Sym->st_shndx]);
VerboseMsg ("Relocation: 0x%08X", *(UINT32*)Targ);
@@ -826,14 +976,52 @@ WriteSections64 (
// Relative relocation: Symbol - Ip + Addend
//
VerboseMsg ("R_X86_64_PC32");
- VerboseMsg ("Offset: 0x%08X, Addend: 0x%08X",
- (UINT32)(SecOffset + (Rel->r_offset - SecShdr->sh_addr)),
+ VerboseMsg ("Offset: 0x%08X, Addend: 0x%08X",
+ (UINT32)(SecOffset + (Rel->r_offset - SecShdr->sh_addr)),
*(UINT32 *)Targ);
*(UINT32 *)Targ = (UINT32) (*(UINT32 *)Targ
+ (mCoffSectionsOffset[Sym->st_shndx] - SymShdr->sh_addr)
- (SecOffset - SecShdr->sh_addr));
VerboseMsg ("Relocation: 0x%08X", *(UINT32 *)Targ);
break;
+ case R_X86_64_GOTPCREL:
+ case R_X86_64_GOTPCRELX:
+ case R_X86_64_REX_GOTPCRELX:
+ VerboseMsg ("R_X86_64_GOTPCREL family");
+ VerboseMsg ("Offset: 0x%08X, Addend: 0x%08X",
+ (UINT32)(SecOffset + (Rel->r_offset - SecShdr->sh_addr)),
+ *(UINT32 *)Targ);
+ GOTEntryRva = Rel->r_offset - Rel->r_addend + *(INT32 *)Targ;
+ FindElfGOTSectionFromGOTEntryElfRva(GOTEntryRva);
+ *(UINT32 *)Targ = (UINT32) (*(UINT32 *)Targ
+ + (mCoffSectionsOffset[mGOTShindex] - mGOTShdr->sh_addr)
+ - (SecOffset - SecShdr->sh_addr));
+ VerboseMsg ("Relocation: 0x%08X", *(UINT32 *)Targ);
+ GOTEntryRva += (mCoffSectionsOffset[mGOTShindex] - mGOTShdr->sh_addr); // ELF Rva -> COFF Rva
+ if (AccumulateCoffGOTEntries((UINT32)GOTEntryRva)) {
+ //
+ // Relocate GOT entry if it's the first time we run into it
+ //
+ Targ = mCoffFile + GOTEntryRva;
+ //
+ // Limitation: The following three statements assume memory
+ // at *Targ is valid because the section containing the GOT
+ // has already been copied from the ELF image to the Coff image.
+ // This pre-condition presently holds because the GOT is placed
+ // in section .text, and the ELF text sections are all copied
+ // prior to reaching this point.
+ // If the pre-condition is violated in the future, this fixup
+ // either needs to be deferred after the GOT section is copied
+ // to the Coff image, or the fixup should be performed on the
+ // source Elf image instead of the destination Coff image.
+ //
+ VerboseMsg ("Offset: 0x%08X, Addend: 0x%016LX",
+ (UINT32)GOTEntryRva,
+ *(UINT64 *)Targ);
+ *(UINT64 *)Targ = *(UINT64 *)Targ - SymShdr->sh_addr + mCoffSectionsOffset[Sym->st_shndx];
+ VerboseMsg ("Relocation: 0x%016LX", *(UINT64*)Targ);
+ }
+ break;
default:
Error (NULL, 0, 3000, "Invalid", "%s unsupported ELF EM_X86_64 relocation 0x%x.", mInImageName, (unsigned) ELF_R_TYPE(Rel->r_info));
}
@@ -972,18 +1160,42 @@ WriteRelocations64 (
case R_X86_64_NONE:
case R_X86_64_PC32:
case R_X86_64_PLT32:
+ case R_X86_64_GOTPCREL:
+ case R_X86_64_GOTPCRELX:
+ case R_X86_64_REX_GOTPCRELX:
break;
case R_X86_64_64:
- VerboseMsg ("EFI_IMAGE_REL_BASED_DIR64 Offset: 0x%08X",
+ VerboseMsg ("EFI_IMAGE_REL_BASED_DIR64 Offset: 0x%08X",
mCoffSectionsOffset[RelShdr->sh_info] + (Rel->r_offset - SecShdr->sh_addr));
CoffAddFixup(
(UINT32) ((UINT64) mCoffSectionsOffset[RelShdr->sh_info]
+ (Rel->r_offset - SecShdr->sh_addr)),
EFI_IMAGE_REL_BASED_DIR64);
break;
- case R_X86_64_32S:
+ //
+ // R_X86_64_32 and R_X86_64_32S are ELF64 relocations emitted when using
+ // the SYSV X64 ABI small non-position-independent code model.
+ // R_X86_64_32 is used for unsigned 32-bit immediates with a 32-bit operand
+ // size. The value is either not extended, or zero-extended to 64 bits.
+ // R_X86_64_32S is used for either signed 32-bit non-rip-relative displacements
+ // or signed 32-bit immediates with a 64-bit operand size. The value is
+ // sign-extended to 64 bits.
+ // EFI_IMAGE_REL_BASED_HIGHLOW is a PE relocation that uses 32-bit arithmetic
+ // for rebasing an image.
+ // EFI PE binaries declare themselves EFI_IMAGE_FILE_LARGE_ADDRESS_AWARE and
+ // may load above 2GB. If an EFI PE binary with a converted R_X86_64_32S
+ // relocation is loaded above 2GB, the value will get sign-extended to the
+ // negative part of the 64-bit address space. The negative part of the 64-bit
+ // address space is unmapped, so accessing such an address page-faults.
+ // In order to support R_X86_64_32S, it is necessary to unset
+ // EFI_IMAGE_FILE_LARGE_ADDRESS_AWARE, and the EFI PE loader must implement
+ // this flag and abstain from loading such a PE binary above 2GB.
+ // Since this feature is not supported, support for R_X86_64_32S (and hence
+ // the small non-position-independent code model) is disabled.
+ //
+ // case R_X86_64_32S:
case R_X86_64_32:
- VerboseMsg ("EFI_IMAGE_REL_BASED_HIGHLOW Offset: 0x%08X",
+ VerboseMsg ("EFI_IMAGE_REL_BASED_HIGHLOW Offset: 0x%08X",
mCoffSectionsOffset[RelShdr->sh_info] + (Rel->r_offset - SecShdr->sh_addr));
CoffAddFixup(
(UINT32) ((UINT64) mCoffSectionsOffset[RelShdr->sh_info]
@@ -1040,10 +1252,32 @@ WriteRelocations64 (
Error (NULL, 0, 3000, "Not Supported", "This tool does not support relocations for ELF with e_machine %u (processor type).", (unsigned) mEhdr->e_machine);
}
}
+ if (mEhdr->e_machine == EM_X86_64 && RelShdr->sh_info == mGOTShindex) {
+ //
+ // Tack relocations for GOT entries after other relocations for
+ // the section the GOT is in, as it's usually found at the end
+ // of the section. This is done in order to maintain Rva order
+ // of Coff relocations.
+ //
+ EmitGOTRelocations();
+ }
}
}
}
+ if (mEhdr->e_machine == EM_X86_64) {
+ //
+ // This is a safety net just in case the GOT is in a section
+ // with no other relocations and the first invocation of
+ // EmitGOTRelocations() above was skipped. This invocation
+ // does not maintain Rva order of Coff relocations.
+ // At present, with a single text section, all references to
+ // the GOT and the GOT itself reside in section .text, so
+ // if there's a GOT at all, the first invocation above
+ // is executed.
+ //
+ EmitGOTRelocations();
+ }
//
// Pad by adding empty entries.
//