MatCat.OpenSource/8sa1-binutils-gdb
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gold: Add endbr64 to IBT TLSDESC PLT entry

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Gold generates:

 c10:   ff 35 da 23 00 00       push   0x23da(%rip)        # 2ff0 <_GLOBAL_OFFSET_TABLE_+0x8>
 c16:   f2 ff 25 c3 23 00 00    bnd jmp *0x23c3(%rip)        # 2fe0 <_DYNAMIC+0x260>
 c1d:   0f 1f 00                nopl   (%rax)

for IBT TLSDESC PLT entry which misses endbr64.  Add endbr64 to generate:

 c10:   f3 0f 1e fa             endbr64
 c14:   ff 35 d6 23 00 00       push   0x23d6(%rip)        # 2ff0 <_GLOBAL_OFFSET_TABLE_+0x8>
 c1a:   ff 25 c0 23 00 00       jmp    *0x23c0(%rip)        # 2fe0 <_DYNAMIC+0x260>

	PR ld/26972
	* x86_64.cc (Output_data_plt_x86_64_ibt::tlsdesc_plt_entry): Add
	endbr64.
	(Output_data_plt_x86_64_ibt::do_fill_tlsdesc_entry): Adjusted.
This commit is contained in:
H.J. Lu 2020-11-29 11:36:13 -08:00
parent 9f1212394f
commit 4bccc875d2
2 changed files with 13 additions and 6 deletions
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7
gold/ChangeLog
View File

@ -1,3 +1,10 @@
2020-11-29 H.J. Lu <hongjiu.lu@intel.com>
PR ld/26972
* x86_64.cc (Output_data_plt_x86_64_ibt::tlsdesc_plt_entry): Add
endbr64.
(Output_data_plt_x86_64_ibt::do_fill_tlsdesc_entry): Adjusted.
2020-11-29 H.J. Lu <hongjiu.lu@intel.com>
PR gold/26939

12
gold/x86_64.cc
View File

@ -2480,11 +2480,11 @@ Output_data_plt_x86_64_ibt<size>::tlsdesc_plt_entry[plt_entry_size] =
{
// From Alexandre Oliva, "Thread-Local Storage Descriptors for IA32
// and AMD64/EM64T", Version 0.9.4 (2005-10-10).
0xf3, 0x0f, 0x1e, 0xfa, // endbr64
0xff, 0x35, // pushq x(%rip)
0, 0, 0, 0, // replaced with address of linkmap GOT entry (at PLTGOT + 8)
0xf2, 0xff, 0x25, // jmpq *y(%rip)
0xff, 0x25, // jmpq *y(%rip)
0, 0, 0, 0, // replaced with offset of reserved TLSDESC_GOT entry
0x0f, 0x1f, 0 // nop
};
template<int size>
@ -2498,15 +2498,15 @@ Output_data_plt_x86_64_ibt<size>::do_fill_tlsdesc_entry(
unsigned int plt_offset)
{
memcpy(pov, tlsdesc_plt_entry, plt_entry_size);
elfcpp::Swap_unaligned<32, false>::writeval(pov + 2,
elfcpp::Swap_unaligned<32, false>::writeval(pov + 6,
(got_address + 8
- (plt_address + plt_offset
+ 6)));
elfcpp::Swap_unaligned<32, false>::writeval(pov + 9,
+ 10)));
elfcpp::Swap_unaligned<32, false>::writeval(pov + 12,
(got_base
+ tlsdesc_got_offset
- (plt_address + plt_offset
+ 13)));
+ 16)));
}
// The .eh_frame unwind information for the PLT.