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Date:   Mon, 23 Aug 2021 10:13:15 -0700
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Subject: [PATCH v2 11/14] x86, module: Ignore __typeid__ relocations
From:   Sami Tolvanen <samitolvanen@google.com>
To:     x86@kernel.org
Cc:     Kees Cook <keescook@chromium.org>,
        Josh Poimboeuf <jpoimboe@redhat.com>,
        Peter Zijlstra <peterz@infradead.org>,
        Nathan Chancellor <nathan@kernel.org>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Sedat Dilek <sedat.dilek@gmail.com>,
        linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org,
        clang-built-linux@googlegroups.com,
        Sami Tolvanen <samitolvanen@google.com>
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Ignore the __typeid__ relocations generated with CONFIG_CFI_CLANG
when loading modules.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
---
 arch/x86/kernel/module.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/arch/x86/kernel/module.c b/arch/x86/kernel/module.c
index 5e9a34b5bd74..c4aeba237eef 100644
--- a/arch/x86/kernel/module.c
+++ b/arch/x86/kernel/module.c
@@ -197,6 +197,10 @@ static int __apply_relocate_add(Elf64_Shdr *sechdrs,
 			val -= (u64)loc;
 			write(loc, &val, 8);
 			break;
+		case R_X86_64_8:
+			if (!strncmp(strtab + sym->st_name, "__typeid__", 10))
+				break;
+			fallthrough;
 		default:
 			pr_err("%s: Unknown rela relocation: %llu\n",
 			       me->name, ELF64_R_TYPE(rel[i].r_info));
-- 
2.33.0.rc2.250.ged5fa647cd-goog