From 628a15e0536abb7658cd243553312d3f65c0aff2 Mon Sep 17 00:00:00 2001 From: Kees Cook Date: Wed, 3 Sep 2025 20:46:41 -0700 Subject: [PATCH] x86/traps: Clarify KCFI instruction layout Just a nit-picky change to the KCFI indirect call check instruction documentation. The addl offset isn't always -4 (it depends on patchable function entry configuration). Signed-off-by: Kees Cook Signed-off-by: Peter Zijlstra (Intel) Link: https://lore.kernel.org/r/20250904034656.3670313-2-kees@kernel.org --- arch/x86/kernel/cfi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/kernel/cfi.c b/arch/x86/kernel/cfi.c index 77086cf565ec1..638eb5c933e00 100644 --- a/arch/x86/kernel/cfi.c +++ b/arch/x86/kernel/cfi.c @@ -27,7 +27,7 @@ static bool decode_cfi_insn(struct pt_regs *regs, unsigned long *target, * for indirect call checks: * *   movl -, %r10d ; 6 bytes - * addl -4(%reg), %r10d ; 4 bytes + * addl -(%reg), %r10d; 4 bytes * je .Ltmp1 ; 2 bytes * ud2 ; <- regs->ip * .Ltmp1: -- 2.47.3