Patch "metag/ptrace: Reject partial NT_METAG_RPIPE writes" has been added to the 4.9-stable tree

Patch "metag/ptrace: Reject partial NT_METAG_RPIPE writes" has been added to the 4.9-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    metag/ptrace: Reject partial NT_METAG_RPIPE writes

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:
     metag-ptrace-reject-partial-nt_metag_rpipe-writes.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@vger.kernel.org> know about it.


>From 7195ee3120d878259e8d94a5d9f808116f34d5ea Mon Sep 17 00:00:00 2001
From: Dave Martin <Dave.Martin@arm.com>
Date: Mon, 27 Mar 2017 15:10:57 +0100
Subject: metag/ptrace: Reject partial NT_METAG_RPIPE writes

From: Dave Martin <Dave.Martin@arm.com>

commit 7195ee3120d878259e8d94a5d9f808116f34d5ea upstream.

It's not clear what behaviour is sensible when doing partial write of
NT_METAG_RPIPE, so just don't bother.

This patch assumes that userspace will never rely on a partial SETREGSET
in this case, since it's not clear what should happen anyway.

Signed-off-by: Dave Martin <Dave.Martin@arm.com>
Acked-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/metag/kernel/ptrace.c |    2 ++
 1 file changed, 2 insertions(+)

--- a/arch/metag/kernel/ptrace.c
+++ b/arch/metag/kernel/ptrace.c
@@ -253,6 +253,8 @@ int metag_rp_state_copyin(struct pt_regs
 	unsigned long long *ptr;
 	int ret, i;
 
+	if (count < 4*13)
+		return -EINVAL;
 	/* Read the entire pipeline before making any changes */
 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 				 &rp, 0, 4*13);


Patches currently in stable-queue which might be from Dave.Martin@arm.com are

queue-4.9/metag-ptrace-reject-partial-nt_metag_rpipe-writes.patch
queue-4.9/metag-ptrace-preserve-previous-registers-for-short-regset-write.patch
queue-4.9/metag-ptrace-provide-default-txstatus-for-short-nt_prstatus.patch
queue-4.9/c6x-ptrace-remove-useless-ptrace_setregset-implementation.patch
queue-4.9/mips-ptrace-preserve-previous-registers-for-short-regset-write.patch
queue-4.9/h8300-ptrace-fix-incorrect-register-transfer-count.patch
queue-4.9/sparc-ptrace-preserve-previous-registers-for-short-regset-write.patch