This patch cleans up and fixes bugs in resume_execution on x86-64.
Kprobes for x86-64 may cause a kernel crash if it inserted on "iret"
instruction.

"call absolute" case 0x9a is invalid on x86-64, so we don't need
treat it, leave it ifdef X86_32.

 - Add "iret"(0xcf) case.to X86_64
 - Fold jmp absolute (0xea) handling into iret/ret/lret handling

Based on patch from Masami Hiramatsu <[EMAIL PROTECTED]>

Signed-off-by: Harvey Harrison <[EMAIL PROTECTED]>
---
 arch/x86/kernel/kprobes.c |   11 +++--------
 1 files changed, 3 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c
index 9130c01..64c702c 100644
--- a/arch/x86/kernel/kprobes.c
+++ b/arch/x86/kernel/kprobes.c
@@ -748,12 +748,13 @@ static void __kprobes resume_execution(struct kprobe *p,
                *tos &= ~(TF_MASK | IF_MASK);
                *tos |= kcb->kprobe_old_flags;
                break;
-       case 0xc2:              /* ret/lret */
+       case 0xc2:              /* iret/ret/lret */
        case 0xc3:
        case 0xca:
        case 0xcb:
+       case 0xcf:
+       case 0xea:              /* jmp absolute -- ip is correct */
 #ifdef CONFIG_X86_32
-       case 0xcf:              /* iret */
                /* ip is already adjusted, no more changes required */
                p->ainsn.boostable = 1;
 #endif
@@ -783,12 +784,6 @@ static void __kprobes resume_execution(struct kprobe *p,
                        goto no_change;
                }
                break;
-       case 0xea:              /* jmp absolute -- ip is correct */
-#ifdef CONFIG_X86_32
-               /* ip is already adjusted, no more changes required */
-               p->ainsn.boostable = 1;
-#endif
-               goto no_change;
        default:
                break;
        }
-- 
1.5.4.rc0.1083.gf568


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to