[PATCH v2 10/14] x86, relocs: Ignore __typeid__ relocations

From: Sami Tolvanen
Date: Mon Aug 23 2021 - 13:14:07 EST


From: Kees Cook <keescook@xxxxxxxxxxxx>

The __typeid__* symbols aren't actually relocations, so they can be
ignored during relocation generation.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
Signed-off-by: Sami Tolvanen <samitolvanen@xxxxxxxxxx>
---
arch/x86/tools/relocs.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/arch/x86/tools/relocs.c b/arch/x86/tools/relocs.c
index 9ba700dc47de..fbc57cc00914 100644
--- a/arch/x86/tools/relocs.c
+++ b/arch/x86/tools/relocs.c
@@ -48,6 +48,7 @@ static const char * const sym_regex_kernel[S_NSYMTYPES] = {
"^(xen_irq_disable_direct_reloc$|"
"xen_save_fl_direct_reloc$|"
"VDSO|"
+ "__typeid__|"
"__crc_)",

/*
@@ -808,6 +809,12 @@ static int do_reloc64(struct section *sec, Elf_Rel *rel, ElfW(Sym) *sym,
symname);
break;

+ case R_X86_64_8:
+ if (!shn_abs || !is_reloc(S_ABS, symname))
+ die("Non-whitelisted %s relocation: %s\n",
+ rel_type(r_type), symname);
+ break;
+
case R_X86_64_32:
case R_X86_64_32S:
case R_X86_64_64:
--
2.33.0.rc2.250.ged5fa647cd-goog