/* AArch64-specific support for NN-bit ELF.
- Copyright (C) 2009-2018 Free Software Foundation, Inc.
+ Copyright (C) 2009-2019 Free Software Foundation, Inc.
Contributed by ARM Ltd.
This file is part of BFD, the Binary File Descriptor library.
#include "bfd.h"
#include "libiberty.h"
#include "libbfd.h"
-#include "bfd_stdint.h"
#include "elf-bfd.h"
#include "bfdlink.h"
#include "objalloc.h"
#define PLT_ENTRY_SIZE (32)
#define PLT_SMALL_ENTRY_SIZE (16)
#define PLT_TLSDESC_ENTRY_SIZE (32)
+/* PLT sizes with BTI insn. */
+#define PLT_BTI_ENTRY_SIZE (36)
+#define PLT_BTI_SMALL_ENTRY_SIZE (20)
+#define PLT_BTI_TLSDESC_ENTRY_SIZE (36)
+/* PLT sizes with PAC insn. */
+#define PLT_PAC_ENTRY_SIZE (36)
+#define PLT_PAC_SMALL_ENTRY_SIZE (20)
+/* PLT sizes with BTI and PAC insn. */
+#define PLT_BTI_PAC_ENTRY_SIZE (40)
+#define PLT_BTI_PAC_SMALL_ENTRY_SIZE (24)
/* Encoding of the nop instruction. */
#define INSN_NOP 0xd503201f
0x1f, 0x20, 0x03, 0xd5, /* nop */
};
+static const bfd_byte elfNN_aarch64_small_plt0_bti_entry[PLT_BTI_ENTRY_SIZE] =
+{
+ 0x5f, 0x24, 0x03, 0xd5, /* bti c. */
+ 0xf0, 0x7b, 0xbf, 0xa9, /* stp x16, x30, [sp, #-16]! */
+ 0x10, 0x00, 0x00, 0x90, /* adrp x16, (GOT+16) */
+#if ARCH_SIZE == 64
+ 0x11, 0x0A, 0x40, 0xf9, /* ldr x17, [x16, #PLT_GOT+0x10] */
+ 0x10, 0x42, 0x00, 0x91, /* add x16, x16,#PLT_GOT+0x10 */
+#else
+ 0x11, 0x0A, 0x40, 0xb9, /* ldr w17, [x16, #PLT_GOT+0x8] */
+ 0x10, 0x22, 0x00, 0x11, /* add w16, w16,#PLT_GOT+0x8 */
+#endif
+ 0x20, 0x02, 0x1f, 0xd6, /* br x17 */
+ 0x1f, 0x20, 0x03, 0xd5, /* nop */
+ 0x1f, 0x20, 0x03, 0xd5, /* nop */
+ 0x1f, 0x20, 0x03, 0xd5, /* nop */
+};
+
+static const bfd_byte elfNN_aarch64_small_plt0_pac_entry[PLT_PAC_ENTRY_SIZE] =
+{
+ 0xf0, 0x7b, 0xbf, 0xa9, /* stp x16, x30, [sp, #-16]! */
+ 0x10, 0x00, 0x00, 0x90, /* adrp x16, (GOT+16) */
+#if ARCH_SIZE == 64
+ 0x11, 0x0A, 0x40, 0xf9, /* ldr x17, [x16, #PLT_GOT+0x10] */
+ 0x10, 0x42, 0x00, 0x91, /* add x16, x16,#PLT_GOT+0x10 */
+#else
+ 0x11, 0x0A, 0x40, 0xb9, /* ldr w17, [x16, #PLT_GOT+0x8] */
+ 0x10, 0x22, 0x00, 0x11, /* add w16, w16,#PLT_GOT+0x8 */
+#endif
+ 0x9f, 0x21, 0x03, 0xd5, /* autia1716 */
+ 0x20, 0x02, 0x1f, 0xd6, /* br x17 */
+ 0x1f, 0x20, 0x03, 0xd5, /* nop */
+ 0x1f, 0x20, 0x03, 0xd5, /* nop */
+ 0x1f, 0x20, 0x03, 0xd5, /* nop */
+};
+
+static const bfd_byte
+elfNN_aarch64_small_plt0_bti_pac_entry[PLT_BTI_PAC_ENTRY_SIZE] =
+{
+ 0x5f, 0x24, 0x03, 0xd5, /* bti c. */
+ 0xf0, 0x7b, 0xbf, 0xa9, /* stp x16, x30, [sp, #-16]! */
+ 0x10, 0x00, 0x00, 0x90, /* adrp x16, (GOT+16) */
+#if ARCH_SIZE == 64
+ 0x11, 0x0A, 0x40, 0xf9, /* ldr x17, [x16, #PLT_GOT+0x10] */
+ 0x10, 0x42, 0x00, 0x91, /* add x16, x16,#PLT_GOT+0x10 */
+#else
+ 0x11, 0x0A, 0x40, 0xb9, /* ldr w17, [x16, #PLT_GOT+0x8] */
+ 0x10, 0x22, 0x00, 0x11, /* add w16, w16,#PLT_GOT+0x8 */
+#endif
+ 0x9f, 0x21, 0x03, 0xd5, /* autia1716 */
+ 0x20, 0x02, 0x1f, 0xd6, /* br x17 */
+ 0x1f, 0x20, 0x03, 0xd5, /* nop */
+ 0x1f, 0x20, 0x03, 0xd5, /* nop */
+ 0x1f, 0x20, 0x03, 0xd5, /* nop */
+};
+
/* Per function entry in a procedure linkage table looks like this
if the distance between the PLTGOT and the PLT is < 4GB use
- these PLT entries. */
+ these PLT entries. Use BTI versions of the PLTs when enabled. */
static const bfd_byte elfNN_aarch64_small_plt_entry[PLT_SMALL_ENTRY_SIZE] =
{
0x10, 0x00, 0x00, 0x90, /* adrp x16, PLTGOT + n * 8 */
0x20, 0x02, 0x1f, 0xd6, /* br x17. */
};
+static const bfd_byte
+elfNN_aarch64_small_plt_bti_entry[PLT_BTI_SMALL_ENTRY_SIZE] =
+{
+ 0x5f, 0x24, 0x03, 0xd5, /* bti c. */
+ 0x10, 0x00, 0x00, 0x90, /* adrp x16, PLTGOT + n * 8 */
+#if ARCH_SIZE == 64
+ 0x11, 0x02, 0x40, 0xf9, /* ldr x17, [x16, PLTGOT + n * 8] */
+ 0x10, 0x02, 0x00, 0x91, /* add x16, x16, :lo12:PLTGOT + n * 8 */
+#else
+ 0x11, 0x02, 0x40, 0xb9, /* ldr w17, [x16, PLTGOT + n * 4] */
+ 0x10, 0x02, 0x00, 0x11, /* add w16, w16, :lo12:PLTGOT + n * 4 */
+#endif
+ 0x20, 0x02, 0x1f, 0xd6, /* br x17. */
+};
+
+static const bfd_byte
+elfNN_aarch64_small_plt_pac_entry[PLT_PAC_SMALL_ENTRY_SIZE] =
+{
+ 0x10, 0x00, 0x00, 0x90, /* adrp x16, PLTGOT + n * 8 */
+#if ARCH_SIZE == 64
+ 0x11, 0x02, 0x40, 0xf9, /* ldr x17, [x16, PLTGOT + n * 8] */
+ 0x10, 0x02, 0x00, 0x91, /* add x16, x16, :lo12:PLTGOT + n * 8 */
+#else
+ 0x11, 0x02, 0x40, 0xb9, /* ldr w17, [x16, PLTGOT + n * 4] */
+ 0x10, 0x02, 0x00, 0x11, /* add w16, w16, :lo12:PLTGOT + n * 4 */
+#endif
+ 0x9f, 0x21, 0x03, 0xd5, /* autia1716 */
+ 0x20, 0x02, 0x1f, 0xd6, /* br x17. */
+};
+
+static const bfd_byte
+elfNN_aarch64_small_plt_bti_pac_entry[PLT_BTI_PAC_SMALL_ENTRY_SIZE] =
+{
+ 0x5f, 0x24, 0x03, 0xd5, /* bti c. */
+ 0x10, 0x00, 0x00, 0x90, /* adrp x16, PLTGOT + n * 8 */
+#if ARCH_SIZE == 64
+ 0x11, 0x02, 0x40, 0xf9, /* ldr x17, [x16, PLTGOT + n * 8] */
+ 0x10, 0x02, 0x00, 0x91, /* add x16, x16, :lo12:PLTGOT + n * 8 */
+#else
+ 0x11, 0x02, 0x40, 0xb9, /* ldr w17, [x16, PLTGOT + n * 4] */
+ 0x10, 0x02, 0x00, 0x11, /* add w16, w16, :lo12:PLTGOT + n * 4 */
+#endif
+ 0x9f, 0x21, 0x03, 0xd5, /* autia1716 */
+ 0x20, 0x02, 0x1f, 0xd6, /* br x17. */
+};
+
static const bfd_byte
elfNN_aarch64_tlsdesc_small_plt_entry[PLT_TLSDESC_ENTRY_SIZE] =
{
0x1f, 0x20, 0x03, 0xd5, /* nop */
};
+static const bfd_byte
+elfNN_aarch64_tlsdesc_small_plt_bti_entry[PLT_BTI_TLSDESC_ENTRY_SIZE] =
+{
+ 0x5f, 0x24, 0x03, 0xd5, /* bti c. */
+ 0xe2, 0x0f, 0xbf, 0xa9, /* stp x2, x3, [sp, #-16]! */
+ 0x02, 0x00, 0x00, 0x90, /* adrp x2, 0 */
+ 0x03, 0x00, 0x00, 0x90, /* adrp x3, 0 */
+#if ARCH_SIZE == 64
+ 0x42, 0x00, 0x40, 0xf9, /* ldr x2, [x2, #0] */
+ 0x63, 0x00, 0x00, 0x91, /* add x3, x3, 0 */
+#else
+ 0x42, 0x00, 0x40, 0xb9, /* ldr w2, [x2, #0] */
+ 0x63, 0x00, 0x00, 0x11, /* add w3, w3, 0 */
+#endif
+ 0x40, 0x00, 0x1f, 0xd6, /* br x2 */
+ 0x1f, 0x20, 0x03, 0xd5, /* nop */
+ 0x1f, 0x20, 0x03, 0xd5, /* nop */
+};
+
#define elf_info_to_howto elfNN_aarch64_info_to_howto
#define elf_info_to_howto_rel elfNN_aarch64_info_to_howto
/* Zero to warn when linking objects with incompatible wchar_t sizes. */
int no_wchar_size_warning;
+
+ /* All GNU_PROPERTY_AARCH64_FEATURE_1_AND properties. */
+ uint32_t gnu_and_prop;
+
+ /* Zero to warn when linking objects with incompatible
+ GNU_PROPERTY_AARCH64_FEATURE_1_BTI. */
+ int no_bti_warn;
+
+ /* PLT type based on security. */
+ aarch64_plt_type plt_type;
};
#define elf_aarch64_tdata(bfd) \
/* The number of bytes in the initial entry in the PLT. */
bfd_size_type plt_header_size;
- /* The number of bytes in the subsequent PLT etries. */
+ /* The bytes of the initial PLT entry. */
+ const bfd_byte *plt0_entry;
+
+ /* The number of bytes in the subsequent PLT entries. */
bfd_size_type plt_entry_size;
+ /* The bytes of the subsequent PLT entry. */
+ const bfd_byte *plt_entry;
+
/* Small local sym cache. */
struct sym_cache sym_cache;
yet. */
bfd_vma tlsdesc_plt;
+ /* The number of bytes in the PLT enty for the TLS descriptor. */
+ bfd_size_type tlsdesc_plt_entry_size;
+
/* The GOT offset for the lazy trampoline. Communicated to the
loader via DT_TLSDESC_GOT. The magic value (bfd_vma) -1
indicates an offset is not allocated. */
}
ret->plt_header_size = PLT_ENTRY_SIZE;
+ ret->plt0_entry = elfNN_aarch64_small_plt0_entry;
ret->plt_entry_size = PLT_SMALL_ENTRY_SIZE;
+ ret->plt_entry = elfNN_aarch64_small_plt_entry;
+ ret->tlsdesc_plt_entry_size = PLT_TLSDESC_ENTRY_SIZE;
ret->obfd = abfd;
ret->dt_tlsdesc_got = (bfd_vma) - 1;
static bfd_boolean
_bfd_aarch64_adrp_p (uint32_t insn)
{
- return ((insn & 0x9f000000) == 0x90000000);
+ return ((insn & AARCH64_ADRP_OP_MASK) == AARCH64_ADRP_OP);
}
{
/* The proper stub has already been created. */
free (stub_name);
+ /* Always update this stub's target since it may have
+ changed after layout. */
+ stub_entry->target_value = sym_value + irela->r_addend;
continue;
}
}
}
+static void
+setup_plt_values (struct bfd_link_info *link_info,
+ aarch64_plt_type plt_type)
+{
+ struct elf_aarch64_link_hash_table *globals;
+ globals = elf_aarch64_hash_table (link_info);
+
+ if (plt_type == PLT_BTI_PAC)
+ {
+ globals->plt_header_size = PLT_BTI_PAC_ENTRY_SIZE;
+ globals->plt0_entry = elfNN_aarch64_small_plt0_bti_pac_entry;
+ globals->tlsdesc_plt_entry_size = PLT_BTI_TLSDESC_ENTRY_SIZE;
+
+ /* Only in ET_EXEC we need PLTn with BTI. */
+ if (bfd_link_pde (link_info))
+ {
+ globals->plt_entry_size = PLT_BTI_PAC_SMALL_ENTRY_SIZE;
+ globals->plt_entry = elfNN_aarch64_small_plt_bti_pac_entry;
+ }
+ else
+ {
+ globals->plt_entry_size = PLT_PAC_SMALL_ENTRY_SIZE;
+ globals->plt_entry = elfNN_aarch64_small_plt_pac_entry;
+ }
+ }
+ else if (plt_type == PLT_BTI)
+ {
+ globals->plt_header_size = PLT_BTI_ENTRY_SIZE;
+ globals->plt0_entry = elfNN_aarch64_small_plt0_bti_entry;
+ globals->tlsdesc_plt_entry_size = PLT_BTI_TLSDESC_ENTRY_SIZE;
+
+ /* Only in ET_EXEC we need PLTn with BTI. */
+ if (bfd_link_pde (link_info))
+ {
+ globals->plt_entry_size = PLT_BTI_SMALL_ENTRY_SIZE;
+ globals->plt_entry = elfNN_aarch64_small_plt_bti_entry;
+ }
+ }
+ else if (plt_type == PLT_PAC)
+ {
+ globals->plt_header_size = PLT_PAC_ENTRY_SIZE;
+ globals->plt0_entry = elfNN_aarch64_small_plt0_pac_entry;
+ globals->tlsdesc_plt_entry_size = PLT_TLSDESC_ENTRY_SIZE;
+ globals->plt_entry_size = PLT_PAC_SMALL_ENTRY_SIZE;
+ globals->plt_entry = elfNN_aarch64_small_plt_pac_entry;
+ }
+}
+
/* Set option values needed during linking. */
void
bfd_elfNN_aarch64_set_options (struct bfd *output_bfd,
int no_wchar_warn, int pic_veneer,
int fix_erratum_835769,
int fix_erratum_843419,
- int no_apply_dynamic_relocs)
+ int no_apply_dynamic_relocs,
+ aarch64_bti_pac_info bp_info)
{
struct elf_aarch64_link_hash_table *globals;
BFD_ASSERT (is_aarch64_elf (output_bfd));
elf_aarch64_tdata (output_bfd)->no_enum_size_warning = no_enum_warn;
elf_aarch64_tdata (output_bfd)->no_wchar_size_warning = no_wchar_warn;
+
+ switch (bp_info.bti_type)
+ {
+ case BTI_WARN:
+ elf_aarch64_tdata (output_bfd)->no_bti_warn = 0;
+ elf_aarch64_tdata (output_bfd)->gnu_and_prop
+ |= GNU_PROPERTY_AARCH64_FEATURE_1_BTI;
+ break;
+
+ default:
+ break;
+ }
+ elf_aarch64_tdata (output_bfd)->plt_type = bp_info.plt_type;
+ setup_plt_values (link_info, bp_info.plt_type);
}
static bfd_vma
+ stub_entry->adrp_offset);
insn = bfd_getl32 (contents + stub_entry->adrp_offset);
- if ((insn & AARCH64_ADRP_OP_MASK) != AARCH64_ADRP_OP)
+ if (!_bfd_aarch64_adrp_p (insn))
abort ();
bfd_signed_vma imm =
weak_undef_p = (h ? h->root.type == bfd_link_hash_undefweak
: bfd_is_und_section (sym_sec));
- abs_symbol_p = (h !=NULL && h->root.type == bfd_link_hash_defined
- && bfd_is_abs_section (h->root.u.def.section));
+ abs_symbol_p = h != NULL && bfd_is_abs_symbol (&h->root);
/* Since STT_GNU_IFUNC symbol must go through PLT, we handle
# define movz_hw_R0 (0x52c00000)
#endif
+/* Structure to hold payload for _bfd_aarch64_erratum_843419_clear_stub,
+ it is used to identify the stub information to reset. */
+
+struct erratum_843419_branch_to_stub_clear_data
+{
+ bfd_vma adrp_offset;
+ asection *output_section;
+};
+
+/* Clear the erratum information for GEN_ENTRY if the ADRP_OFFSET and
+ section inside IN_ARG matches. The clearing is done by setting the
+ stub_type to none. */
+
+static bfd_boolean
+_bfd_aarch64_erratum_843419_clear_stub (struct bfd_hash_entry *gen_entry,
+ void *in_arg)
+{
+ struct elf_aarch64_stub_hash_entry *stub_entry
+ = (struct elf_aarch64_stub_hash_entry *) gen_entry;
+ struct erratum_843419_branch_to_stub_clear_data *data
+ = (struct erratum_843419_branch_to_stub_clear_data *) in_arg;
+
+ if (stub_entry->target_section != data->output_section
+ || stub_entry->stub_type != aarch64_stub_erratum_843419_veneer
+ || stub_entry->adrp_offset != data->adrp_offset)
+ return TRUE;
+
+ /* Change the stub type instead of removing the entry, removing from the hash
+ table would be slower and we have already reserved the memory for the entry
+ so there wouldn't be much gain. Changing the stub also keeps around a
+ record of what was there before. */
+ stub_entry->stub_type = aarch64_stub_none;
+
+ /* We're done and there could have been only one matching stub at that
+ particular offset, so abort further traversal. */
+ return FALSE;
+}
+
+/* TLS Relaxations may relax an adrp sequence that matches the erratum 843419
+ sequence. In this case the erratum no longer applies and we need to remove
+ the entry from the pending stub generation. This clears matching adrp insn
+ at ADRP_OFFSET in INPUT_SECTION in the stub table defined in GLOBALS. */
+
+static void
+clear_erratum_843419_entry (struct elf_aarch64_link_hash_table *globals,
+ bfd_vma adrp_offset, asection *input_section)
+{
+ if (globals->fix_erratum_843419)
+ {
+ struct erratum_843419_branch_to_stub_clear_data data;
+ data.adrp_offset = adrp_offset;
+ data.output_section = input_section;
+
+ bfd_hash_traverse (&globals->stub_hash_table,
+ _bfd_aarch64_erratum_843419_clear_stub, &data);
+ }
+}
+
/* Handle TLS relaxations. Relaxing is possible for symbols that use
R_AARCH64_TLSDESC_ADR_{PAGE, LD64_LO12_NC, ADD_LO12_NC} during a static
link.
static bfd_reloc_status_type
elfNN_aarch64_tls_relax (struct elf_aarch64_link_hash_table *globals,
- bfd *input_bfd, bfd_byte *contents,
- Elf_Internal_Rela *rel, struct elf_link_hash_entry *h)
+ bfd *input_bfd, asection *input_section,
+ bfd_byte *contents, Elf_Internal_Rela *rel,
+ struct elf_link_hash_entry *h)
{
bfd_boolean is_local = h == NULL;
unsigned int r_type = ELFNN_R_TYPE (rel->r_info);
Where R is x for LP64, and w for ILP32. */
bfd_putl32 (movz_R0, contents + rel->r_offset);
+ /* We have relaxed the adrp into a mov, we may have to clear any
+ pending erratum fixes. */
+ clear_erratum_843419_entry (globals, rel->r_offset, input_section);
return bfd_reloc_continue;
}
else
{
insn = bfd_getl32 (contents + rel->r_offset);
bfd_putl32 (movz_R0 | (insn & 0x1f), contents + rel->r_offset);
+ /* We have relaxed the adrp into a mov, we may have to clear any
+ pending erratum fixes. */
+ clear_erratum_843419_entry (globals, rel->r_offset, input_section);
}
return bfd_reloc_continue;
howto = elfNN_aarch64_howto_from_bfd_reloc (bfd_r_type);
BFD_ASSERT (howto != NULL);
r_type = howto->type;
- r = elfNN_aarch64_tls_relax (globals, input_bfd, contents, rel, h);
+ r = elfNN_aarch64_tls_relax (globals, input_bfd, input_section,
+ contents, rel, h);
unresolved_reloc = 0;
}
else
if (h != NULL
/* This is an absolute symbol. It represents a value instead
of an address. */
- && ((h->root.type == bfd_link_hash_defined
- && bfd_is_abs_section (h->root.u.def.section))
+ && (bfd_is_abs_symbol (&h->root)
/* This is an undefined symbol. */
|| h->root.type == bfd_link_hash_undefined))
break;
case BFD_RELOC_AARCH64_TLSLD_ADD_LO12_NC:
case BFD_RELOC_AARCH64_TLSLD_ADR_PAGE21:
case BFD_RELOC_AARCH64_TLSLD_ADR_PREL21:
- case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G1:
- case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G1_NC:
- case BFD_RELOC_AARCH64_TLSLE_MOVW_TPREL_G2:
{
unsigned got_type;
unsigned old_got_type;
if (!elfNN_aarch64_output_map_sym (osi, AARCH64_MAP_INSN, addr))
return FALSE;
break;
+ case aarch64_stub_none:
+ break;
default:
abort ();
/* Make room for this entry. For now we only create the
small model PLT entries. We later need to find a way
of relaxing into these from the large model PLT entries. */
- s->size += PLT_SMALL_ENTRY_SIZE;
+ s->size += htab->plt_entry_size;
/* We also need to make an entry in the .got.plt section, which
will be placed in the .got section by the linker script. */
if (htab->tlsdesc_plt)
{
if (htab->root.splt->size == 0)
- htab->root.splt->size += PLT_ENTRY_SIZE;
+ htab->root.splt->size += htab->plt_header_size;
htab->tlsdesc_plt = htab->root.splt->size;
- htab->root.splt->size += PLT_TLSDESC_ENTRY_SIZE;
+ htab->root.splt->size += htab->tlsdesc_plt_entry_size;
/* If we're not using lazy TLS relocations, don't generate the
GOT entry required. */
&& (!add_dynamic_entry (DT_TLSDESC_PLT, 0)
|| !add_dynamic_entry (DT_TLSDESC_GOT, 0)))
return FALSE;
+
+ if ((elf_aarch64_tdata (output_bfd)->plt_type == PLT_BTI_PAC)
+ && (!add_dynamic_entry (DT_AARCH64_BTI_PLT, 0)
+ || !add_dynamic_entry (DT_AARCH64_PAC_PLT, 0)))
+ return FALSE;
+
+ else if ((elf_aarch64_tdata (output_bfd)->plt_type == PLT_BTI)
+ && !add_dynamic_entry (DT_AARCH64_BTI_PLT, 0))
+ return FALSE;
+
+ else if ((elf_aarch64_tdata (output_bfd)->plt_type == PLT_PAC)
+ && !add_dynamic_entry (DT_AARCH64_PAC_PLT, 0))
+ return FALSE;
}
if (relocs)
gotplt->output_offset + got_offset;
/* Copy in the boiler-plate for the PLTn entry. */
- memcpy (plt_entry, elfNN_aarch64_small_plt_entry, PLT_SMALL_ENTRY_SIZE);
+ memcpy (plt_entry, htab->plt_entry, htab->plt_entry_size);
+
+ /* First instruction in BTI enabled PLT stub is a BTI
+ instruction so skip it. */
+ if (elf_aarch64_tdata (output_bfd)->plt_type & PLT_BTI
+ && elf_elfheader (output_bfd)->e_type == ET_EXEC)
+ plt_entry = plt_entry + 4;
/* Fill in the top 21 bits for this: ADRP x16, PLT_GOT + n * 8.
ADRP: ((PG(S+A)-PG(P)) >> 12) & 0x1fffff */
bfd_vma plt_base;
- memcpy (htab->root.splt->contents, elfNN_aarch64_small_plt0_entry,
- PLT_ENTRY_SIZE);
+ memcpy (htab->root.splt->contents, htab->plt0_entry,
+ htab->plt_header_size);
elf_section_data (htab->root.splt->output_section)->this_hdr.sh_entsize =
- PLT_ENTRY_SIZE;
+ htab->plt_header_size;
plt_got_2nd_ent = (htab->root.sgotplt->output_section->vma
+ htab->root.sgotplt->output_offset
plt_base = htab->root.splt->output_section->vma +
htab->root.splt->output_offset;
+ /* First instruction in BTI enabled PLT stub is a BTI
+ instruction so skip it. */
+ bfd_byte *plt0_entry = htab->root.splt->contents;
+ if (elf_aarch64_tdata (output_bfd)->plt_type & PLT_BTI)
+ plt0_entry = plt0_entry + 4;
+
/* Fill in the top 21 bits for this: ADRP x16, PLT_GOT + n * 8.
ADRP: ((PG(S+A)-PG(P)) >> 12) & 0x1fffff */
elf_aarch64_update_plt_entry (output_bfd, BFD_RELOC_AARCH64_ADR_HI21_PCREL,
- htab->root.splt->contents + 4,
+ plt0_entry + 4,
PG (plt_got_2nd_ent) - PG (plt_base + 4));
elf_aarch64_update_plt_entry (output_bfd, BFD_RELOC_AARCH64_LDSTNN_LO12,
- htab->root.splt->contents + 8,
+ plt0_entry + 8,
PG_OFFSET (plt_got_2nd_ent));
elf_aarch64_update_plt_entry (output_bfd, BFD_RELOC_AARCH64_ADD_LO12,
- htab->root.splt->contents + 12,
+ plt0_entry + 12,
PG_OFFSET (plt_got_2nd_ent));
}
bfd_put_NN (output_bfd, (bfd_vma) 0,
htab->root.sgot->contents + htab->dt_tlsdesc_got);
+ const bfd_byte *entry = elfNN_aarch64_tlsdesc_small_plt_entry;
+ htab->tlsdesc_plt_entry_size = PLT_TLSDESC_ENTRY_SIZE;
+
+ aarch64_plt_type type = elf_aarch64_tdata (output_bfd)->plt_type;
+ if (type == PLT_BTI || type == PLT_BTI_PAC)
+ {
+ entry = elfNN_aarch64_tlsdesc_small_plt_bti_entry;
+ htab->tlsdesc_plt_entry_size = PLT_BTI_TLSDESC_ENTRY_SIZE;
+ }
+
memcpy (htab->root.splt->contents + htab->tlsdesc_plt,
- elfNN_aarch64_tlsdesc_small_plt_entry,
- sizeof (elfNN_aarch64_tlsdesc_small_plt_entry));
+ entry, htab->tlsdesc_plt_entry_size);
{
bfd_vma adrp1_addr =
bfd_byte *plt_entry =
htab->root.splt->contents + htab->tlsdesc_plt;
+ /* First instruction in BTI enabled PLT stub is a BTI
+ instruction so skip it. */
+ if (type & PLT_BTI)
+ {
+ plt_entry = plt_entry + 4;
+ adrp1_addr = adrp1_addr + 4;
+ adrp2_addr = adrp2_addr + 4;
+ }
+
/* adrp x2, DT_TLSDESC_GOT */
elf_aarch64_update_plt_entry (output_bfd,
BFD_RELOC_AARCH64_ADR_HI21_PCREL,
return TRUE;
}
+/* Check if BTI enabled PLTs are needed. Returns the type needed. */
+static aarch64_plt_type
+get_plt_type (bfd *abfd)
+{
+ aarch64_plt_type ret = PLT_NORMAL;
+ bfd_byte *contents, *extdyn, *extdynend;
+ asection *sec = bfd_get_section_by_name (abfd, ".dynamic");
+ if (!sec || !bfd_malloc_and_get_section (abfd, sec, &contents))
+ return ret;
+ extdyn = contents;
+ extdynend = contents + sec->size;
+ for (; extdyn < extdynend; extdyn += sizeof (ElfNN_External_Dyn))
+ {
+ Elf_Internal_Dyn dyn;
+ bfd_elfNN_swap_dyn_in (abfd, extdyn, &dyn);
+
+ /* Let's check the processor specific dynamic array tags. */
+ bfd_vma tag = dyn.d_tag;
+ if (tag < DT_LOPROC || tag > DT_HIPROC)
+ continue;
+
+ switch (tag)
+ {
+ case DT_AARCH64_BTI_PLT:
+ ret |= PLT_BTI;
+ break;
+
+ case DT_AARCH64_PAC_PLT:
+ ret |= PLT_PAC;
+ break;
+
+ default: break;
+ }
+ }
+ free (contents);
+ return ret;
+}
+
+static long
+elfNN_aarch64_get_synthetic_symtab (bfd *abfd,
+ long symcount,
+ asymbol **syms,
+ long dynsymcount,
+ asymbol **dynsyms,
+ asymbol **ret)
+{
+ elf_aarch64_tdata (abfd)->plt_type = get_plt_type (abfd);
+ return _bfd_elf_get_synthetic_symtab (abfd, symcount, syms,
+ dynsymcount, dynsyms, ret);
+}
+
/* Return address for Ith PLT stub in section PLT, for relocation REL
or (bfd_vma) -1 if it should not be included. */
elfNN_aarch64_plt_sym_val (bfd_vma i, const asection *plt,
const arelent *rel ATTRIBUTE_UNUSED)
{
- return plt->vma + PLT_ENTRY_SIZE + i * PLT_SMALL_ENTRY_SIZE;
+ size_t plt0_size = PLT_ENTRY_SIZE;
+ size_t pltn_size = PLT_SMALL_ENTRY_SIZE;
+
+ if (elf_aarch64_tdata (plt->owner)->plt_type == PLT_BTI_PAC)
+ {
+ plt0_size = PLT_BTI_PAC_ENTRY_SIZE;
+ if (elf_elfheader (plt->owner)->e_type == ET_EXEC)
+ pltn_size = PLT_BTI_PAC_SMALL_ENTRY_SIZE;
+ else
+ pltn_size = PLT_PAC_SMALL_ENTRY_SIZE;
+ }
+ else if (elf_aarch64_tdata (plt->owner)->plt_type == PLT_BTI)
+ {
+ plt0_size = PLT_BTI_ENTRY_SIZE;
+ if (elf_elfheader (plt->owner)->e_type == ET_EXEC)
+ pltn_size = PLT_BTI_SMALL_ENTRY_SIZE;
+ }
+ else if (elf_aarch64_tdata (plt->owner)->plt_type == PLT_PAC)
+ {
+ plt0_size = PLT_PAC_ENTRY_SIZE;
+ pltn_size = PLT_PAC_SMALL_ENTRY_SIZE;
+ }
+
+ return plt->vma + plt0_size + i * pltn_size;
}
/* Returns TRUE if NAME is an AArch64 mapping symbol.
sym->flags |= BSF_KEEP;
}
+/* Implement elf_backend_setup_gnu_properties for AArch64. It serves as a
+ wrapper function for _bfd_aarch64_elf_link_setup_gnu_properties to account
+ for the effect of GNU properties of the output_bfd. */
+static bfd *
+elfNN_aarch64_link_setup_gnu_properties (struct bfd_link_info *info)
+{
+ uint32_t prop = elf_aarch64_tdata (info->output_bfd)->gnu_and_prop;
+ bfd *pbfd = _bfd_aarch64_elf_link_setup_gnu_properties (info, &prop);
+ elf_aarch64_tdata (info->output_bfd)->gnu_and_prop = prop;
+ elf_aarch64_tdata (info->output_bfd)->plt_type
+ |= (prop & GNU_PROPERTY_AARCH64_FEATURE_1_BTI) ? PLT_BTI : 0;
+ setup_plt_values (info, elf_aarch64_tdata (info->output_bfd)->plt_type);
+ return pbfd;
+}
+
+/* Implement elf_backend_merge_gnu_properties for AArch64. It serves as a
+ wrapper function for _bfd_aarch64_elf_merge_gnu_properties to account
+ for the effect of GNU properties of the output_bfd. */
+static bfd_boolean
+elfNN_aarch64_merge_gnu_properties (struct bfd_link_info *info,
+ bfd *abfd, bfd *bbfd,
+ elf_property *aprop,
+ elf_property *bprop)
+{
+ uint32_t prop
+ = elf_aarch64_tdata (info->output_bfd)->gnu_and_prop;
+
+ /* If output has been marked with BTI using command line argument, give out
+ warning if necessary. */
+ /* Properties are merged per type, hence only check for warnings when merging
+ GNU_PROPERTY_AARCH64_FEATURE_1_AND. */
+ if (((aprop && aprop->pr_type == GNU_PROPERTY_AARCH64_FEATURE_1_AND)
+ || (bprop && bprop->pr_type == GNU_PROPERTY_AARCH64_FEATURE_1_AND))
+ && (prop & GNU_PROPERTY_AARCH64_FEATURE_1_BTI)
+ && (!elf_aarch64_tdata (info->output_bfd)->no_bti_warn))
+ {
+ if ((aprop && !(aprop->u.number & GNU_PROPERTY_AARCH64_FEATURE_1_BTI))
+ || !aprop)
+ {
+ _bfd_error_handler (_("%pB: warning: BTI turned on by --force-bti when "
+ "all inputs do not have BTI in NOTE section."),
+ abfd);
+ }
+ if ((bprop && !(bprop->u.number & GNU_PROPERTY_AARCH64_FEATURE_1_BTI))
+ || !bprop)
+ {
+ _bfd_error_handler (_("%pB: warning: BTI turned on by --force-bti when "
+ "all inputs do not have BTI in NOTE section."),
+ bbfd);
+ }
+ }
+
+ return _bfd_aarch64_elf_merge_gnu_properties (info, abfd, aprop,
+ bprop, prop);
+}
/* We use this so we can override certain functions
(though currently we don't). */
#define bfd_elfNN_find_nearest_line \
elfNN_aarch64_find_nearest_line
+#define bfd_elfNN_get_synthetic_symtab \
+ elfNN_aarch64_get_synthetic_symtab
+
#define bfd_elfNN_mkobject \
elfNN_aarch64_mkobject
#define elf_backend_symbol_processing \
elfNN_aarch64_backend_symbol_processing
+#define elf_backend_setup_gnu_properties \
+ elfNN_aarch64_link_setup_gnu_properties
+
+#define elf_backend_merge_gnu_properties \
+ elfNN_aarch64_merge_gnu_properties
+
#define elf_backend_can_refcount 1
#define elf_backend_can_gc_sections 1
#define elf_backend_plt_readonly 1