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 <[email protected]> Signed-off-by: Dave Hansen <[email protected]> Tested-by: Joerg Roedel <[email protected]> Acked-by: Tom Lendacky <[email protected]> Link: https://lkml.kernel.org/r/[email protected]
ashr · Nov 30, 2021 · 23ef731 · 23ef731
1 parent d58071a
commit 23ef731
Showing 1 changed file with 3 additions and 2 deletions.
diff --git 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);