[PATCH v6 22/29] x86/asm: Avoid generating unused kprobe sections

From: Kees Cook
Date: Fri Aug 21 2020 - 15:55:16 EST


When !CONFIG_KPROBES, do not generate kprobe sections. This makes
sure there are no unexpected sections encountered by the linker scripts.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
arch/x86/include/asm/asm.h | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/asm.h b/arch/x86/include/asm/asm.h
index 5c15f95b1ba7..4712206c4325 100644
--- a/arch/x86/include/asm/asm.h
+++ b/arch/x86/include/asm/asm.h
@@ -138,11 +138,15 @@
# define _ASM_EXTABLE_FAULT(from, to) \
_ASM_EXTABLE_HANDLE(from, to, ex_handler_fault)

-# define _ASM_NOKPROBE(entry) \
+# ifdef CONFIG_KPROBES
+# define _ASM_NOKPROBE(entry) \
.pushsection "_kprobe_blacklist","aw" ; \
_ASM_ALIGN ; \
_ASM_PTR (entry); \
.popsection
+# else
+# define _ASM_NOKPROBE(entry)
+# endif

#else /* ! __ASSEMBLY__ */
# define _EXPAND_EXTABLE_HANDLE(x) #x
--
2.25.1