Patch "metag/ptrace: Provide default TXSTATUS for short NT_PRSTATUS" has been added to the 3.18-stable tree

Patch "metag/ptrace: Provide default TXSTATUS for short NT_PRSTATUS" has been added to the 3.18-stable tree

[gregkh]

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

    metag/ptrace: Provide default TXSTATUS for short NT_PRSTATUS

to the 3.18-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-provide-default-txstatus-for-short-nt_prstatus.patch
and it can be found in the queue-3.18 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 5fe81fe98123ce41265c65e95d34418d30d005d1 Mon Sep 17 00:00:00 2001
From: Dave Martin <Dave.Martin@arm.com>
Date: Mon, 27 Mar 2017 15:10:56 +0100
Subject: metag/ptrace: Provide default TXSTATUS for short NT_PRSTATUS

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

commit 5fe81fe98123ce41265c65e95d34418d30d005d1 upstream.

Ensure that if userspace supplies insufficient data to PTRACE_SETREGSET
to fill TXSTATUS, a well-defined default value is used, based on the
task's current value.

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

---
 arch/metag/kernel/ptrace.c |   15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

--- a/arch/metag/kernel/ptrace.c
+++ b/arch/metag/kernel/ptrace.c
@@ -24,6 +24,16 @@
  * user_regset definitions.
  */
 
+static unsigned long user_txstatus(const struct pt_regs *regs)
+{
+	unsigned long data = (unsigned long)regs->ctx.Flags;
+
+	if (regs->ctx.SaveMask & TBICTX_CBUF_BIT)
+		data |= USER_GP_REGS_STATUS_CATCH_BIT;
+
+	return data;
+}
+
 int metag_gp_regs_copyout(const struct pt_regs *regs,
 			  unsigned int pos, unsigned int count,
 			  void *kbuf, void __user *ubuf)
@@ -62,9 +72,7 @@ int metag_gp_regs_copyout(const struct p
 	if (ret)
 		goto out;
 	/* TXSTATUS */
-	data = (unsigned long)regs->ctx.Flags;
-	if (regs->ctx.SaveMask & TBICTX_CBUF_BIT)
-		data |= USER_GP_REGS_STATUS_CATCH_BIT;
+	data = user_txstatus(regs);
 	ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
 				  &data, 4*25, 4*26);
 	if (ret)
@@ -119,6 +127,7 @@ int metag_gp_regs_copyin(struct pt_regs
 	if (ret)
 		goto out;
 	/* TXSTATUS */
+	data = user_txstatus(regs);
 	ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf,
 				 &data, 4*25, 4*26);
 	if (ret)


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

queue-3.18/metag-ptrace-reject-partial-nt_metag_rpipe-writes.patch
queue-3.18/metag-ptrace-preserve-previous-registers-for-short-regset-write.patch
queue-3.18/metag-ptrace-provide-default-txstatus-for-short-nt_prstatus.patch
queue-3.18/c6x-ptrace-remove-useless-ptrace_setregset-implementation.patch
queue-3.18/mips-ptrace-preserve-previous-registers-for-short-regset-write.patch
queue-3.18/sparc-ptrace-preserve-previous-registers-for-short-regset-write.patch