linux-kernel - [PATCH] x86/extable: Annotate ex_handler_msr

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 20 May 2022 21:27:29 +0200
From:   Borislav Petkov <bp@...en8.de>
To:     X86 ML <x86@...nel.org>
Cc:     LKML <linux-kernel@...r.kernel.org>
Subject: [PATCH] x86/extable: Annotate ex_handler_msr_mce() as a dead end

From: Borislav Petkov <bp@...e.de>

Fix

  vmlinux.o: warning: objtool: fixup_exception+0x2d6: unreachable instruction

Signed-off-by: Borislav Petkov <bp@...e.de>
---
 arch/x86/include/asm/extable.h | 4 ++--
 tools/objtool/check.c          | 3 ++-
 2 files changed, 4 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/extable.h b/arch/x86/include/asm/extable.h
index 155c991ba95e..6ac53e98fff4 100644
--- a/arch/x86/include/asm/extable.h
+++ b/arch/x86/include/asm/extable.h
@@ -42,9 +42,9 @@ extern int ex_get_fixup_type(unsigned long ip);
 extern void early_fixup_exception(struct pt_regs *regs, int trapnr);
 
 #ifdef CONFIG_X86_MCE
-extern void ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr);
+extern void __noreturn ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr);
 #else
-static inline void ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr) { }
+static inline void __noreturn ex_handler_msr_mce(struct pt_regs *regs, bool wrmsr) { }
 #endif
 
 #if defined(CONFIG_BPF_JIT) && defined(CONFIG_X86_64)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 190b2f6e360a..c23e46c4a882 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -185,7 +185,8 @@ static bool __dead_end_function(struct objtool_file *file, struct symbol *func,
 		"do_group_exit",
 		"stop_this_cpu",
 		"__invalid_creds",
-               "cpu_startup_entry",
+		"cpu_startup_entry",
+		"ex_handler_msr_mce",
 	};
 
 	if (!func)
-- 
2.35.1