arm64: Add support for GOT and PCREL32 relocations.

grub-core/kern/arm64/dl.c

@@ -25,14 +25,9 @@
 #include <grub/i18n.h>
 #include <grub/cpu/reloc.h>
 
-struct trampoline
-{
 #define LDR 0x58000050
 #define BR 0xd61f0200
-  grub_uint32_t ldr; /* ldr	x16, 8 */
+
-  grub_uint32_t br; /* br x16 */
-  grub_uint64_t addr;
-};
 
 /*
  * Check if EHDR is a valid ELF header.
@@ -53,42 +48,6 @@ grub_arch_dl_check_header (void *ehdr)
 
 #pragma GCC diagnostic ignored "-Wcast-align"
 
-grub_err_t
-grub_arch_dl_get_tramp_got_size (const void *ehdr, grub_size_t *tramp,
-				 grub_size_t *got)
-{
-  const Elf_Ehdr *e = ehdr;
-  const Elf_Shdr *s;
-  unsigned i;
-
-  *tramp = 0;
-  *got = 0;
-
-  for (i = 0, s = (const Elf_Shdr *) ((grub_addr_t) e + e->e_shoff);
-       i < e->e_shnum;
-       i++, s = (const Elf_Shdr *) ((grub_addr_t) s + e->e_shentsize))
-    if (s->sh_type == SHT_REL || s->sh_type == SHT_RELA)
-      {
-	const Elf_Rel *rel, *max;
-
-	for (rel = (const Elf_Rel *) ((grub_addr_t) e + s->sh_offset),
-	       max = rel + s->sh_size / s->sh_entsize;
-	     rel < max;
-	     rel = (const Elf_Rel *) ((grub_addr_t) rel + s->sh_entsize))
-	  switch (ELF_R_TYPE (rel->r_info))
-	    {
-	    case R_AARCH64_CALL26:
-	    case R_AARCH64_JUMP26:
-	      {
-		*tramp += sizeof (struct trampoline);
-		break;
-	      }
-	    }
-      }
-
-  return GRUB_ERR_NONE;
-}
-
 /*
  * Unified function for both REL and RELA 
  */
@@ -97,6 +56,7 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr,
 			       Elf_Shdr *s, grub_dl_segment_t seg)
 {
   Elf_Rel *rel, *max;
+  unsigned unmatched_adr_got_page = 0;
 
   for (rel = (Elf_Rel *) ((char *) ehdr + s->sh_offset),
 	 max = (Elf_Rel *) ((char *) rel + s->sh_size);
@@ -145,7 +105,7 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr,
 
 	    if (!grub_arm_64_check_xxxx26_offset (offset))
 	      {
-		struct trampoline *tp = mod->trampptr;
+		struct grub_arm64_trampoline *tp = mod->trampptr;
 		mod->trampptr = tp + 1;
 		tp->ldr = LDR;
 		tp->br = BR;
@@ -160,6 +120,56 @@ grub_arch_dl_relocate_symbols (grub_dl_t mod, void *ehdr,
 	    grub_arm64_set_xxxx26_offset (place, offset);
 	  }
 	  break;
+	case R_AARCH64_PREL32:
+	  {
+	    grub_int64_t value;
+	    Elf64_Word *addr32 = place;
+	    value = ((grub_int32_t) *addr32) + sym_addr -
+	      (Elf64_Xword) (grub_addr_t) seg->addr - rel->r_offset;
+	    if (value != (grub_int32_t) value)
+	      return grub_error (GRUB_ERR_BAD_MODULE, "relocation out of range");
+	    grub_dprintf("dl", "  reloc_prel32 %p => 0x%016llx\n",
+			  place, (unsigned long long) sym_addr);
+	    *addr32 = value;
+	  }
+	  break;
+	case R_AARCH64_ADR_GOT_PAGE:
+	  {
+	    grub_uint64_t *gp = mod->gotptr;
+	    Elf_Rela *rel2;
+	    grub_int64_t gpoffset = ((grub_uint64_t) gp & ~0xfffULL) - (((grub_uint64_t) place) & ~0xfffULL);
+	    *gp = (grub_uint64_t) sym_addr;
+	    mod->gotptr = gp + 1;
+	    unmatched_adr_got_page++;
+	    grub_dprintf("dl", "  reloc_got %p => 0x%016llx (0x%016llx)\n",
+			 place, (unsigned long long) sym_addr, (unsigned long long) gp);
+	    if (!grub_arm64_check_hi21_signed (gpoffset))
+		return grub_error (GRUB_ERR_BAD_MODULE,
+				   "HI21 out of range");
+	    grub_arm64_set_hi21(place, gpoffset);
+	    for (rel2 = (Elf_Rela *) ((char *) rel + s->sh_entsize);
+		 rel2 < (Elf_Rela *) max;
+		 rel2 = (Elf_Rela *) ((char *) rel2 + s->sh_entsize))
+	      if (ELF_R_SYM (rel2->r_info)
+		  == ELF_R_SYM (rel->r_info)
+		  && ((Elf_Rela *) rel)->r_addend == rel2->r_addend
+		  && ELF_R_TYPE (rel2->r_info) == R_AARCH64_LD64_GOT_LO12_NC)
+		{
+		  grub_arm64_set_abs_lo12_ldst64 ((void *) ((grub_addr_t) seg->addr + rel2->r_offset),
+						  (grub_uint64_t)gp);
+		  break;
+		}
+	    if (rel2 >= (Elf_Rela *) max)
+	      return grub_error (GRUB_ERR_BAD_MODULE,
+				 "ADR_GOT_PAGE without matching LD64_GOT_LO12_NC");
+	  }
+	  break;
+	case R_AARCH64_LD64_GOT_LO12_NC:
+	  if (unmatched_adr_got_page == 0)
+	    return grub_error (GRUB_ERR_BAD_MODULE,
+			       "LD64_GOT_LO12_NC without matching ADR_GOT_PAGE");
+	  unmatched_adr_got_page--;
+	  break;
 	case R_AARCH64_ADR_PREL_PG_HI21:
 	  {
 	    grub_int64_t offset = (sym_addr & ~0xfffULL) - (((grub_uint64_t) place) & ~0xfffULL);

grub-core/kern/arm64/dl_helper.c

@@ -93,3 +93,42 @@ grub_arm64_set_abs_lo12_ldst64 (grub_uint32_t *place, grub_int64_t target)
   *place &= insmask;
   *place |= grub_cpu_to_le32 (target << 7) & ~insmask;
 }
+
+#pragma GCC diagnostic ignored "-Wcast-align"
+
+grub_err_t
+grub_arm64_dl_get_tramp_got_size (const void *ehdr, grub_size_t *tramp,
+				  grub_size_t *got)
+{
+  const Elf64_Ehdr *e = ehdr;
+  const Elf64_Shdr *s;
+  unsigned i;
+
+  *tramp = 0;
+  *got = 0;
+
+  for (i = 0, s = (Elf64_Shdr *) ((char *) e + grub_le_to_cpu64 (e->e_shoff));
+       i < grub_le_to_cpu16 (e->e_shnum);
+       i++, s = (Elf64_Shdr *) ((char *) s + grub_le_to_cpu16 (e->e_shentsize)))
+    if (s->sh_type == grub_cpu_to_le32_compile_time (SHT_REL)
+	|| s->sh_type == grub_cpu_to_le32_compile_time (SHT_RELA))
+      {
+	const Elf64_Rela *rel, *max;
+
+	for (rel = (Elf64_Rela *) ((char *) e + grub_le_to_cpu64 (s->sh_offset)),
+	       max = (const Elf64_Rela *) ((grub_addr_t) rel + grub_le_to_cpu64 (s->sh_size));
+	     rel < max; rel = (const Elf64_Rela *) ((grub_addr_t) rel + grub_le_to_cpu64 (s->sh_entsize)))
+	  switch (ELF64_R_TYPE (rel->r_info))
+	    {
+	    case R_AARCH64_CALL26:
+	    case R_AARCH64_JUMP26:
+	      *tramp += sizeof (struct grub_arm64_trampoline);
+	      break;
+	    case R_AARCH64_ADR_GOT_PAGE:
+	      *got += 8;
+	      break;
+	    }
+      }
+
+  return GRUB_ERR_NONE;
+}

include/grub/arm64/reloc.h

@@ -19,6 +19,13 @@
 #ifndef GRUB_ARM64_RELOC_H
 #define GRUB_ARM64_RELOC_H 1
 
+struct grub_arm64_trampoline
+{
+  grub_uint32_t ldr; /* ldr	x16, 8 */
+  grub_uint32_t br; /* br x16 */
+  grub_uint64_t addr;
+};
+
 int grub_arm_64_check_xxxx26_offset (grub_int64_t offset);
 void
 grub_arm64_set_xxxx26_offset (grub_uint32_t *place, grub_int64_t offset);

include/grub/dl.h

@@ -263,11 +263,16 @@ void grub_arch_dl_init_linker (void);
 grub_err_t
 grub_ia64_dl_get_tramp_got_size (const void *ehdr, grub_size_t *tramp,
 				 grub_size_t *got);
+grub_err_t
+grub_arm64_dl_get_tramp_got_size (const void *ehdr, grub_size_t *tramp,
+				  grub_size_t *got);
 
 #if defined (__ia64__)
 #define GRUB_ARCH_DL_TRAMP_ALIGN GRUB_IA64_DL_TRAMP_ALIGN
 #define GRUB_ARCH_DL_GOT_ALIGN GRUB_IA64_DL_GOT_ALIGN
 #define grub_arch_dl_get_tramp_got_size grub_ia64_dl_get_tramp_got_size
+#elif defined (__aarch64__)
+#define grub_arch_dl_get_tramp_got_size grub_arm64_dl_get_tramp_got_size
 #else
 grub_err_t
 grub_arch_dl_get_tramp_got_size (const void *ehdr, grub_size_t *tramp,

include/grub/elf.h

@@ -2068,11 +2068,14 @@ typedef Elf32_Addr Elf32_Conflict;
 #define R_AARCH64_NONE			0	/* No relocation.  */
 #define R_AARCH64_ABS64			257	/* Direct 64 bit. */
 #define R_AARCH64_ABS32			258	/* Direct 32 bit.  */
+#define R_AARCH64_PREL32		261
 #define R_AARCH64_ADR_PREL_PG_HI21	275
 #define R_AARCH64_ADD_ABS_LO12_NC	277
 #define R_AARCH64_LDST64_ABS_LO12_NC	286
 #define R_AARCH64_JUMP26		282	/* 26-bit relative. */
 #define R_AARCH64_CALL26		283	/* 26-bit relative. */
+#define R_AARCH64_ADR_GOT_PAGE		311
+#define R_AARCH64_LD64_GOT_LO12_NC	312
 #define R_AARCH64_COPY			1024	/* Copy symbol at runtime.  */
 #define R_AARCH64_GLOB_DAT		1025	/* Create GOT entry.  */
 #define R_AARCH64_JUMP_SLOT		1026	/* Create PLT entry.  */

include/grub/util/mkimage.h

@@ -30,7 +30,7 @@ struct grub_mkimage_layout
   size_t align;
   grub_size_t ia64jmp_off;
   grub_size_t tramp_off;
-  grub_size_t ia64_got_off;
+  grub_size_t got_off;
   grub_size_t got_size;
   unsigned ia64jmpnum;
   grub_uint32_t bss_start;

util/grub-mkimagexx.c

@@ -717,6 +717,7 @@ SUFFIX (relocate_addresses) (Elf_Ehdr *e, Elf_Shdr *sections,
 #ifdef MKIMAGE_ELF64
   struct grub_ia64_trampoline *tr = (void *) (pe_target + tramp_off);
   grub_uint64_t *gpptr = (void *) (pe_target + got_off);
+  unsigned unmatched_adr_got_page = 0;
 #define MASK19 ((1 << 19) - 1)
 #else
   grub_uint32_t *tr = (void *) (pe_target + tramp_off);
@@ -965,6 +966,18 @@ SUFFIX (relocate_addresses) (Elf_Ehdr *e, Elf_Shdr *sections,
 		       *target = grub_host_to_target64 (grub_target_to_host64 (*target) + sym_addr);
 		     }
 		     break;
+		   case R_AARCH64_PREL32:
+		     {
+		       grub_uint32_t *t32 = (grub_uint32_t *) target;
+		       *t32 = grub_host_to_target64 (grub_target_to_host32 (*t32)
+						     + sym_addr
+						     - target_section_addr - offset
+						     - image_target->vaddr_offset);
+		       grub_util_info ("relocating an R_AARCH64_PREL32 entry to 0x%x at the offset 0x%"
+				       GRUB_HOST_PRIxLONG_LONG,
+				       *t32, (unsigned long long) offset);
+		       break;
+		     }
 		   case R_AARCH64_ADD_ABS_LO12_NC:
 		     grub_arm64_set_abs_lo12 ((grub_uint32_t *) target,
 					      sym_addr);
@@ -985,6 +998,41 @@ SUFFIX (relocate_addresses) (Elf_Ehdr *e, Elf_Shdr *sections,
 						     sym_addr);
 		     }
 		     break;
+		   case R_AARCH64_ADR_GOT_PAGE:
+		     {
+		       Elf64_Rela *rel2;
+		       grub_int64_t gpoffset = (((char *) gpptr - (char *) pe_target + image_target->vaddr_offset) & ~0xfffULL)
+			 - ((offset + target_section_addr + image_target->vaddr_offset) & ~0xfffULL);
+		       unsigned k;
+		       *gpptr = grub_host_to_target64 (sym_addr);
+		       unmatched_adr_got_page++;
+		       if (!grub_arm64_check_hi21_signed (gpoffset))
+			 grub_util_error ("HI21 out of range");
+		       grub_arm64_set_hi21((grub_uint32_t *)target,
+					   gpoffset);
+		       for (k = 0, rel2 = (Elf_Rela *) ((char *) r + r_size);
+			    k < num_rs;
+			    k++, rel2 = (Elf_Rela *) ((char *) rel2 + r_size))
+			 if (ELF_R_SYM (rel2->r_info)
+			     == ELF_R_SYM (r->r_info)
+			     && r->r_addend == rel2->r_addend
+			     && ELF_R_TYPE (rel2->r_info) == R_AARCH64_LD64_GOT_LO12_NC)
+			   {
+			     grub_arm64_set_abs_lo12_ldst64 ((grub_uint32_t *) SUFFIX (get_target_address) (e, target_section,
+													    grub_target_to_host (rel2->r_offset), image_target),
+							     ((char *) gpptr - (char *) pe_target + image_target->vaddr_offset));
+			     break;
+			   }
+		       if (k >= num_rs)
+			 grub_util_error ("ADR_GOT_PAGE without matching LD64_GOT_LO12_NC");
+		       gpptr++;
+	             }
+		     break;
+		   case R_AARCH64_LD64_GOT_LO12_NC:
+		     if (unmatched_adr_got_page == 0)
+		       grub_util_error ("LD64_GOT_LO12_NC without matching ADR_GOT_PAGE");
+		     unmatched_adr_got_page--;
+		     break;
 		   case R_AARCH64_ADR_PREL_PG_HI21:
 		     {
 		       sym_addr &= ~0xfffULL;
@@ -1329,6 +1377,7 @@ translate_relocation_pe (struct translate_context *ctx,
 	  /* Relative relocations do not require fixup entries. */
 	case R_AARCH64_CALL26:
 	case R_AARCH64_JUMP26:
+	case R_AARCH64_PREL32:
 	  break;
 	  /* Page-relative relocations do not require fixup entries. */
 	case R_AARCH64_ADR_PREL_PG_HI21:
@@ -1339,6 +1388,11 @@ translate_relocation_pe (struct translate_context *ctx,
 	case R_AARCH64_LDST64_ABS_LO12_NC:
 	  break;
 
+	  /* GOT is relocated separately.  */
+	case R_AARCH64_ADR_GOT_PAGE:
+	case R_AARCH64_LD64_GOT_LO12_NC:
+	  break;
+
 	default:
 	  grub_util_error (_("relocation 0x%x is not implemented yet"),
 			   (unsigned int) ELF_R_TYPE (info));
@@ -1547,9 +1601,9 @@ finish_reloc_translation (struct translate_context *ctx, struct grub_mkimage_lay
 
 
 static void
-translate_reloc_jumpers (struct translate_context *ctx,
+create_u64_fixups (struct translate_context *ctx,
-			 Elf_Addr jumpers, grub_size_t njumpers,
+		   Elf_Addr jumpers, grub_size_t njumpers,
-			 const struct grub_install_image_target_desc *image_target)
+		   const struct grub_install_image_target_desc *image_target)
 {
   unsigned i;
   assert (image_target->id == IMAGE_EFI);
@@ -1614,11 +1668,17 @@ make_reloc_section (Elf_Ehdr *e, struct grub_mkimage_layout *layout,
       }
 
   if (image_target->elf_target == EM_IA_64)
-    translate_reloc_jumpers (&ctx,
+    create_u64_fixups (&ctx,
-			     layout->ia64jmp_off
+		       layout->ia64jmp_off
-			     + image_target->vaddr_offset,
+		       + image_target->vaddr_offset,
-			     2 * layout->ia64jmpnum + (layout->got_size / 8),
+		       2 * layout->ia64jmpnum,
-			     image_target);
+		       image_target);
+  if (image_target->elf_target == EM_IA_64 || image_target->elf_target == EM_AARCH64)
+    create_u64_fixups (&ctx,
+		       layout->got_off
+		       + image_target->vaddr_offset,
+		       (layout->got_size / 8),
+		       image_target);
 
   finish_reloc_translation (&ctx, layout, image_target);
 }
@@ -1944,7 +2004,18 @@ SUFFIX (grub_mkimage_load_image) (const char *kernel_path,
 						     image_target);
 	  layout->kernel_size += 16 * layout->ia64jmpnum;
 
-	  layout->ia64_got_off = layout->kernel_size;
+	  layout->got_off = layout->kernel_size;
+	  layout->kernel_size += ALIGN_UP (layout->got_size, 16);
+	}
+      if (image_target->elf_target == EM_AARCH64)
+	{
+	  grub_size_t tramp;
+
+	  layout->kernel_size = ALIGN_UP (layout->kernel_size, 16);
+
+	  grub_arm64_dl_get_tramp_got_size (e, &tramp, &layout->got_size);
+
+	  layout->got_off = layout->kernel_size;
 	  layout->kernel_size += ALIGN_UP (layout->got_size, 16);
 	}
 #endif
@@ -1977,7 +2048,7 @@ SUFFIX (grub_mkimage_load_image) (const char *kernel_path,
 				   section_entsize,
 				   num_sections, strtab,
 				   out_img, layout->tramp_off,
-				   layout->ia64_got_off,
+				   layout->got_off,
 				   image_target);
 
       make_reloc_section (e, layout,

util/grub-module-verifier.c

@@ -107,11 +107,14 @@ struct grub_module_verifier_arch archs[] = {
       R_AARCH64_ABS64,
       R_AARCH64_CALL26,
       R_AARCH64_JUMP26,
+      R_AARCH64_ADR_GOT_PAGE,
+      R_AARCH64_LD64_GOT_LO12_NC,
       -1
     }, (int[]){
       R_AARCH64_ADR_PREL_PG_HI21,
       R_AARCH64_ADD_ABS_LO12_NC,
       R_AARCH64_LDST64_ABS_LO12_NC,
+      R_AARCH64_PREL32,
       -1
     }
   },

util/grub-module-verifierXX.c

@@ -319,6 +319,40 @@ section_check_relocations (const struct grub_module_verifier_arch *arch, void *e
 	continue;
       grub_util_error ("relocation 0x%x is not module-local", type);
     }
+#if defined(MODULEVERIFIER_ELF64)
+  if (arch->machine == EM_AARCH64)
+    {
+      unsigned unmatched_adr_got_page = 0;
+      Elf_Rela *rel2;
+      for (rel = (Elf_Rel *) ((char *) ehdr + grub_target_to_host (s->sh_offset)),
+	     max = (Elf_Rel *) ((char *) rel + grub_target_to_host (s->sh_size));
+	   rel < max;
+	   rel = (Elf_Rel *) ((char *) rel + grub_target_to_host (s->sh_entsize)))
+	{
+	  switch (ELF_R_TYPE (grub_target_to_host (rel->r_info)))
+	    {
+	    case R_AARCH64_ADR_GOT_PAGE:
+	      unmatched_adr_got_page++;
+	      for (rel2 = (Elf_Rela *) ((char *) rel + grub_target_to_host (s->sh_entsize));
+		   rel2 < (Elf_Rela *) max;
+		   rel2 = (Elf_Rela *) ((char *) rel2 + grub_target_to_host (s->sh_entsize)))
+		if (ELF_R_SYM (rel2->r_info)
+		    == ELF_R_SYM (rel->r_info)
+		    && ((Elf_Rela *) rel)->r_addend == rel2->r_addend
+		    && ELF_R_TYPE (rel2->r_info) == R_AARCH64_LD64_GOT_LO12_NC)
+		  break;
+	      if (rel2 >= (Elf_Rela *) max)
+		grub_util_error ("ADR_GOT_PAGE without matching LD64_GOT_LO12_NC");
+	      break;
+	    case R_AARCH64_LD64_GOT_LO12_NC:
+	      if (unmatched_adr_got_page == 0)
+		grub_util_error ("LD64_GOT_LO12_NC without matching ADR_GOT_PAGE");
+	      unmatched_adr_got_page--;
+	      break;
+	    }
+	}
+    }
+#endif
 }
 
 static void