From b34ca60148c53971d373643195cc5c4d5d20be78 Mon Sep 17 00:00:00 2001 From: Dave Martin Date: Thu, 5 Jan 2017 16:50:57 +0000 Subject: [PATCH] powerpc/ptrace: Preserve previous TM fprs/vsrs on short regset write Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the check pointed registers, the thread's old check pointed registers are preserved. Fixes: 9d3918f7c0e5 ("powerpc/ptrace: Enable support for NT_PPC_CVSX") Fixes: 19cbcbf75a0c ("powerpc/ptrace: Enable support for NT_PPC_CFPR") Cc: stable@vger.kernel.org # v4.8+ Signed-off-by: Dave Martin Signed-off-by: Michael Ellerman --- arch/powerpc/kernel/ptrace.c | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index 10543eb..925a4ef 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -1026,6 +1026,10 @@ static int tm_cfpr_set(struct task_struct *target, flush_fp_to_thread(target); flush_altivec_to_thread(target); + for (i = 0; i < 32; i++) + buf[i] = target->thread.TS_CKFPR(i); + buf[32] = target->thread.ckfp_state.fpscr; + /* copy to local buffer then write that out */ i = user_regset_copyin(&pos, &count, &kbuf, &ubuf, buf, 0, -1); if (i) @@ -1290,6 +1294,9 @@ static int tm_cvsx_set(struct task_struct *target, flush_altivec_to_thread(target); flush_vsx_to_thread(target); + for (i = 0; i < 32 ; i++) + buf[i] = target->thread.ckfp_state.fpr[i][TS_VSRLOWOFFSET]; + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, buf, 0, 32 * sizeof(double)); if (!ret) -- 2.7.4