1 files changed, 7 insertions, 42 deletions

diff --git a/arch/x86/kernel/umip.c b/arch/x86/kernel/umip.c
index 2c304fd0bb1a..f6225bf22c02 100644
--- a/arch/x86/kernel/umip.c
+++ b/arch/x86/kernel/umip.c
@@ -335,63 +335,28 @@ static void force_sig_info_umip_fault(void __user *addr, struct pt_regs *regs)
  */
 bool fixup_umip_exception(struct pt_regs *regs)
 {
-	int not_copied, nr_copied, reg_offset, dummy_data_size, umip_inst;
-	unsigned long seg_base = 0, *reg_addr;
+	int nr_copied, reg_offset, dummy_data_size, umip_inst;
 	/* 10 bytes is the maximum size of the result of UMIP instructions */
 	unsigned char dummy_data[10] = { 0 };
 	unsigned char buf[MAX_INSN_SIZE];
+	unsigned long *reg_addr;
 	void __user *uaddr;
 	struct insn insn;
-	int seg_defs;
 
 	if (!regs)
 		return false;
 
-	/*
-	 * If not in user-space long mode, a custom code segment could be in
-	 * use. This is true in protected mode (if the process defined a local
-	 * descriptor table), or virtual-8086 mode. In most of the cases
-	 * seg_base will be zero as in USER_CS.
-	 */
-	if (!user_64bit_mode(regs))
-		seg_base = insn_get_seg_base(regs, INAT_SEG_REG_CS);
-
-	if (seg_base == -1L)
-		return false;
-
-	not_copied = copy_from_user(buf, (void __user *)(seg_base + regs->ip),
-				    sizeof(buf));
-	nr_copied = sizeof(buf) - not_copied;
+	nr_copied = insn_fetch_from_user(regs, buf);
 
 	/*
-	 * The copy_from_user above could have failed if user code is protected
-	 * by a memory protection key. Give up on emulation in such a case.
-	 * Should we issue a page fault?
+	 * The insn_fetch_from_user above could have failed if user code
+	 * is protected by a memory protection key. Give up on emulation
+	 * in such a case.  Should we issue a page fault?
 	 */
 	if (!nr_copied)
 		return false;
 
-	insn_init(&insn, buf, nr_copied, user_64bit_mode(regs));
-
-	/*
-	 * Override the default operand and address sizes with what is specified
-	 * in the code segment descriptor. The instruction decoder only sets
-	 * the address size it to either 4 or 8 address bytes and does nothing
-	 * for the operand bytes. This OK for most of the cases, but we could
-	 * have special cases where, for instance, a 16-bit code segment
-	 * descriptor is used.
-	 * If there is an address override prefix, the instruction decoder
-	 * correctly updates these values, even for 16-bit defaults.
-	 */
-	seg_defs = insn_get_code_seg_params(regs);
-	if (seg_defs == -EINVAL)
-		return false;
-
-	insn.addr_bytes = INSN_CODE_SEG_ADDR_SZ(seg_defs);
-	insn.opnd_bytes = INSN_CODE_SEG_OPND_SZ(seg_defs);
-
-	insn_get_length(&insn);
-	if (nr_copied < insn.length)
+	if (!insn_decode(&insn, regs, buf, nr_copied))
 		return false;
 
 	umip_inst = identify_insn(&insn);