Currently ptrace doesn't flush the register state when the
checkpointed GPRs of a 32-bit thread are accessed. This can cause core
dumps to have stale data in the checkpointed GPR note.
---
arch/powerpc/kernel/ptrace.c | 20 ++++++++++++++++++++
1 file changed, 20 insertions(+)
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c
index 6618570c6d56..be8ca03a0bd5 100644
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -2124,6 +2124,16 @@ static int tm_cgpr32_get(struct task_struct *target,
unsigned int pos, unsigned int count,
void *kbuf, void __user *ubuf)
{
+ if (!cpu_has_feature(CPU_FTR_TM))
+ return -ENODEV;
+
+ if (!MSR_TM_ACTIVE(target->thread.regs->msr))
+ return -ENODATA;
+
+ flush_tmregs_to_thread(target);
+ flush_fp_to_thread(target);
+ flush_altivec_to_thread(target);
+
return gpr32_get_common(target, regset, pos, count, kbuf, ubuf,
&target->thread.ckpt_regs.gpr[0]);
}
@@ -2133,6 +2143,16 @@ static int tm_cgpr32_set(struct task_struct *target,
unsigned int pos, unsigned int count,
const void *kbuf, const void __user *ubuf)
{
+ if (!cpu_has_feature(CPU_FTR_TM))
+ return -ENODEV;
+
+ if (!MSR_TM_ACTIVE(target->thread.regs->msr))
+ return -ENODATA;
+
+ flush_tmregs_to_thread(target);
+ flush_fp_to_thread(target);
+ flush_altivec_to_thread(target);
+
return gpr32_set_common(target, regset, pos, count, kbuf, ubuf,
&target->thread.ckpt_regs.gpr[0]);
}
--
2.13.6
