3.2.87-rc1 review patch. If anyone has any objections, please let me know.
------------------
From: Dave Martin <Dave.Martin@xxxxxxx>
commit 99dfe80a2a246c600440a815741fd2e74a8b4977 upstream.
Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET
to fill all the registers, the thread's old registers are preserved.
Fixes: c6e6771b87d4 ("powerpc: Introduce VSX thread_struct and CONFIG_VSX")
Signed-off-by: Dave Martin <Dave.Martin@xxxxxxx>
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
[bwh: Backported to 3.2:
- fpscr and fpr are direct members of struct thread_struct
- Use memcpy() for fpscr, like the reverse copy below, to avoid type error
- Adjust context]
Signed-off-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
---
arch/powerpc/kernel/ptrace.c | 7 +++++++
1 file changed, 7 insertions(+)
--- a/arch/powerpc/kernel/ptrace.c
+++ b/arch/powerpc/kernel/ptrace.c
@@ -359,6 +359,10 @@ static int fpr_set(struct task_struct *t
flush_fp_to_thread(target);
#ifdef CONFIG_VSX
+ for (i = 0; i < 32 ; i++)
+ buf[i] = target->thread.TS_FPR(i);
+ memcpy(&buf[32], &target->thread.fpscr, sizeof(double));
+
/* copy to local buffer then write that out */
i = user_regset_copyin(&pos, &count, &kbuf, &ubuf, buf, 0, -1);
if (i)
@@ -501,6 +505,9 @@ static int vsr_set(struct task_struct *t
flush_vsx_to_thread(target);
+ for (i = 0; i < 32 ; i++)
+ buf[i] = target->thread.fpr[i][TS_VSRLOWOFFSET];
+
ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
buf, 0, 32 * sizeof(double));
for (i = 0; i < 32 ; i++)