From 23ef731e4365196bfc186358eb4f6265d60ab352 Mon Sep 17 00:00:00 2001 From: "Kirill A. Shutemov" Date: Tue, 30 Nov 2021 21:49:30 +0300 Subject: [PATCH] x86/insn-eval: Handle insn_get_opcode() failure is_string_insn() calls insn_get_opcode() that can fail, but does not handle the failure. is_string_insn() interface does not allow to communicate an error to the caller. Push insn_get_opcode() to the only non-static user of is_string_insn() and fail it early if insn_get_opcode() fails. [ dhansen: fix tabs-versus-spaces breakage ] Signed-off-by: Kirill A. Shutemov Signed-off-by: Dave Hansen Tested-by: Joerg Roedel Acked-by: Tom Lendacky Link: https://lkml.kernel.org/r/20211130184933.31005-2-kirill.shutemov@linux.intel.com --- arch/x86/lib/insn-eval.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/lib/insn-eval.c b/arch/x86/lib/insn-eval.c index eb3ccffb9b9d..1c51e8a415e2 100644 --- a/arch/x86/lib/insn-eval.c +++ b/arch/x86/lib/insn-eval.c @@ -37,8 +37,6 @@ enum reg_type { */ static bool is_string_insn(struct insn *insn) { - insn_get_opcode(insn); - /* All string instructions have a 1-byte opcode. */ if (insn->opcode.nbytes != 1) return false; @@ -1405,6 +1403,9 @@ void __user *insn_get_addr_ref(struct insn *insn, struct pt_regs *regs) if (!insn || !regs) return (void __user *)-1L; + if (insn_get_opcode(insn)) + return (void __user *)-1L; + switch (insn->addr_bytes) { case 2: return get_addr_ref_16(insn, regs); -- 2.20.1