This is a note to let you know that I've just added the patch titled arm64/ptrace: Preserve previous registers for short regset write - 2 to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: arm64-ptrace-preserve-previous-registers-for-short-regset-write-2.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 9dd73f72f218320c6c90da5f834996e7360dc227 Mon Sep 17 00:00:00 2001 From: Dave Martin <Dave.Martin@xxxxxxx> Date: Wed, 18 Jan 2017 16:25:21 +0000 Subject: arm64/ptrace: Preserve previous registers for short regset write - 2 From: Dave Martin <Dave.Martin@xxxxxxx> commit 9dd73f72f218320c6c90da5f834996e7360dc227 upstream. Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET to fill all the registers, the thread's old registers are preserved. Fixes: 766a85d7bc5d ("arm64: ptrace: add NT_ARM_SYSTEM_CALL regset") Signed-off-by: Dave Martin <Dave.Martin@xxxxxxx> Acked-by: Will Deacon <Will.Deacon@xxxxxxx> Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm64/kernel/ptrace.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -676,7 +676,8 @@ static int system_call_set(struct task_s unsigned int pos, unsigned int count, const void *kbuf, const void __user *ubuf) { - int syscallno, ret; + int syscallno = task_pt_regs(target)->syscallno; + int ret; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &syscallno, 0, -1); if (ret) Patches currently in stable-queue which might be from Dave.Martin@xxxxxxx are queue-4.9/arm64-ptrace-preserve-previous-registers-for-short-regset-write-3.patch queue-4.9/arm64-ptrace-reject-attempts-to-set-incomplete-hardware-breakpoint-fields.patch queue-4.9/powerpc-ptrace-preserve-previous-tm-fprs-vsrs-on-short-regset-write.patch queue-4.9/arm64-ptrace-preserve-previous-registers-for-short-regset-write-2.patch queue-4.9/arm64-ptrace-avoid-uninitialised-struct-padding-in-fpr_set.patch queue-4.9/arm64-ptrace-preserve-previous-registers-for-short-regset-write.patch queue-4.9/powerpc-ptrace-preserve-previous-fprs-vsrs-on-short-regset-write.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html