[RFC PATCH v0 09/19] x86/mce: Convert to insn_decode()

Borislav Petkov
2020-11-24T10:21:12Z

Simplify code, no functional changes.

Signed-off-by: Borislav Petkov <bp@suse.de>
---
arch/x86/kernel/cpu/mce/severity.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/cpu/mce/severity.c b/arch/x86/kernel/cpu/mce/severity.c
index 83df991314c5..a2136ced9d73 100644
--- a/arch/x86/kernel/cpu/mce/severity.c
+++ b/arch/x86/kernel/cpu/mce/severity.c
@@ -218,15 +218,15 @@ static struct severity {
static bool is_copy_from_user(struct pt_regs *regs)
{
u8 insn_buf[MAX_INSN_SIZE];
- struct insn insn;
unsigned long addr;
+ struct insn insn;
+ int ret;

if (copy_from_kernel_nofault(insn_buf, (void *)regs->ip, MAX_INSN_SIZE))
return false;

- kernel_insn_init(&insn, insn_buf, MAX_INSN_SIZE);
- insn_get_opcode(&insn);
- if (!insn.opcode.got)
+ ret = insn_decode(&insn, insn_buf, MAX_INSN_SIZE, INSN_MODE_KERN);
+ if (ret < 0)
return false;

switch (insn.opcode.value) {
@@ -234,10 +234,6 @@ static bool is_copy_from_user(struct pt_regs *regs)
case 0x8A: case 0x8B:
/* MOVZ mem,reg */
case 0xB60F: case 0xB70F:
- insn_get_modrm(&insn);
- insn_get_sib(&insn);
- if (!insn.modrm.got || !insn.sib.got)
- return false;
addr = (unsigned long)insn_get_addr_ref(&insn, regs);
break;
/* REP MOVS */
--
2.21.0