| author |  Jakub Konka <kubkon@jakubkonka.com> 2023-10-14 01:33:25+02:00 |
| committer | Jakub Konka <kubkon@jakubkonka.com> 2023-10-16 19:33:06+02:00 |
| log | b3d98a4b88514b1e8d2cc07ef05c218f50f5f5d8 |
| tree | 986501178b8bcf292699a92720d774faa928a5c9 |
| parent | 315cd7623eccdbce009845083b708f1c9bb6c672 |
elf: emit dynamic base relocs for .zig.got entries when required
2 files changed, 23 insertions(+), 2 deletions(-)
src
src/link/Elf.zig+3-2
| ... | @@ -3747,7 +3747,7 @@ fn initSections(self: *Elf) !void { | ... | @@ -3747,7 +3747,7 @@ fn initSections(self: *Elf) !void { |
| 3747 | 3747 | ||
| 3748 | const needs_rela_dyn = blk: { | 3748 | const needs_rela_dyn = blk: { |
| 3749 | if (self.got.flags.needs_rela or self.got.flags.needs_tlsld or | 3749 | if (self.got.flags.needs_rela or self.got.flags.needs_tlsld or |
| 3750 | self.copy_rel.symbols.items.len > 0) break :blk true; | 3750 | self.zig_got.flags.needs_rela or self.copy_rel.symbols.items.len > 0) break :blk true; |
| 3751 | if (self.zig_module_index) |index| { | 3751 | if (self.zig_module_index) |index| { |
| 3752 | if (self.file(index).?.zig_module.num_dynrelocs > 0) break :blk true; | 3752 | if (self.file(index).?.zig_module.num_dynrelocs > 0) break :blk true; |
| 3753 | } | 3753 | } |
| ... | @@ -4319,7 +4319,7 @@ fn updateSectionSizes(self: *Elf) !void { | ... | @@ -4319,7 +4319,7 @@ fn updateSectionSizes(self: *Elf) !void { |
| 4319 | } | 4319 | } |
| 4320 | 4320 | ||
| 4321 | if (self.rela_dyn_section_index) |shndx| { | 4321 | if (self.rela_dyn_section_index) |shndx| { |
| 4322 | var num = self.got.numRela(self) + self.copy_rel.numRela(); | 4322 | var num = self.got.numRela(self) + self.copy_rel.numRela() + self.zig_got.numRela(); |
| 4323 | if (self.zig_module_index) |index| { | 4323 | if (self.zig_module_index) |index| { |
| 4324 | num += self.file(index).?.zig_module.num_dynrelocs; | 4324 | num += self.file(index).?.zig_module.num_dynrelocs; |
| 4325 | } | 4325 | } |
| ... | @@ -4901,6 +4901,7 @@ fn writeSyntheticSections(self: *Elf) !void { | ... | @@ -4901,6 +4901,7 @@ fn writeSyntheticSections(self: *Elf) !void { |
| 4901 | const shdr = self.shdrs.items[shndx]; | 4901 | const shdr = self.shdrs.items[shndx]; |
| 4902 | try self.got.addRela(self); | 4902 | try self.got.addRela(self); |
| 4903 | try self.copy_rel.addRela(self); | 4903 | try self.copy_rel.addRela(self); |
| 4904 | try self.zig_got.addRela(self); | ||
| 4904 | self.sortRelaDyn(); | 4905 | self.sortRelaDyn(); |
| 4905 | try self.base.file.?.pwriteAll(mem.sliceAsBytes(self.rela_dyn.items), shdr.sh_offset); | 4906 | try self.base.file.?.pwriteAll(mem.sliceAsBytes(self.rela_dyn.items), shdr.sh_offset); |
| 4906 | } | 4907 | } |
src/link/Elf/synthetic_sections.zig+20
| ... | @@ -251,6 +251,9 @@ pub const ZigGotSection = struct { | ... | @@ -251,6 +251,9 @@ pub const ZigGotSection = struct { |
| 251 | entry.* = sym_index; | 251 | entry.* = sym_index; |
| 252 | const symbol = elf_file.symbol(sym_index); | 252 | const symbol = elf_file.symbol(sym_index); |
| 253 | symbol.flags.has_zig_got = true; | 253 | symbol.flags.has_zig_got = true; |
| 254 | if (elf_file.base.options.pic) { | ||
| 255 | zig_got.flags.needs_rela = true; | ||
| 256 | } | ||
| 254 | if (symbol.extra(elf_file)) |extra| { | 257 | if (symbol.extra(elf_file)) |extra| { |
| 255 | var new_extra = extra; | 258 | var new_extra = extra; |
| 256 | new_extra.zig_got = index; | 259 | new_extra.zig_got = index; |
| ... | @@ -338,6 +341,23 @@ pub const ZigGotSection = struct { | ... | @@ -338,6 +341,23 @@ pub const ZigGotSection = struct { |
| 338 | } | 341 | } |
| 339 | } | 342 | } |
| 340 | 343 | ||
| 344 | pub fn numRela(zig_got: ZigGotSection) usize { | ||
| 345 | return zig_got.entries.items.len; | ||
| 346 | } | ||
| 347 | |||
| 348 | pub fn addRela(zig_got: ZigGotSection, elf_file: *Elf) !void { | ||
| 349 | try elf_file.rela_dyn.ensureUnusedCapacity(elf_file.base.allocator, zig_got.numRela()); | ||
| 350 | for (zig_got.entries.items) |entry| { | ||
| 351 | const symbol = elf_file.symbol(entry); | ||
| 352 | const offset = symbol.zigGotAddress(elf_file); | ||
| 353 | elf_file.addRelaDynAssumeCapacity(.{ | ||
| 354 | .offset = offset, | ||
| 355 | .type = elf.R_X86_64_RELATIVE, | ||
| 356 | .addend = @intCast(symbol.address(.{ .plt = false }, elf_file)), | ||
| 357 | }); | ||
| 358 | } | ||
| 359 | } | ||
| 360 | |||
| 341 | pub fn updateSymtabSize(zig_got: *ZigGotSection, elf_file: *Elf) void { | 361 | pub fn updateSymtabSize(zig_got: *ZigGotSection, elf_file: *Elf) void { |
| 342 | _ = elf_file; | 362 | _ = elf_file; |
| 343 | zig_got.output_symtab_size.nlocals = @as(u32, @intCast(zig_got.entries.items.len)); | 363 | zig_got.output_symtab_size.nlocals = @as(u32, @intCast(zig_got.entries.items.len)); |