Patch "MIPS: Also verify sizeof `elf_fpreg_t' with PTRACE_SETREGSET" has been added to the 4.4-stable tree

[<gregkh@linuxfoundation.org>]

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

    MIPS: Also verify sizeof `elf_fpreg_t' with PTRACE_SETREGSET

to the 4.4-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:
     mips-also-verify-sizeof-elf_fpreg_t-with-ptrace_setregset.patch
and it can be found in the queue-4.4 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 006501e039eec411842bb3150c41358867d320c2 Mon Sep 17 00:00:00 2001
From: "Maciej W. Rozycki" <macro@mips.com>
Date: Mon, 11 Dec 2017 22:55:40 +0000
Subject: MIPS: Also verify sizeof `elf_fpreg_t' with PTRACE_SETREGSET

From: Maciej W. Rozycki <macro@mips.com>

commit 006501e039eec411842bb3150c41358867d320c2 upstream.

Complement commit d614fd58a283 ("mips/ptrace: Preserve previous
registers for short regset write") and like with the PTRACE_GETREGSET
ptrace(2) request also apply a BUILD_BUG_ON check for the size of the
`elf_fpreg_t' type in the PTRACE_SETREGSET request handler.

Signed-off-by: Maciej W. Rozycki <macro@mips.com>
Fixes: d614fd58a283 ("mips/ptrace: Preserve previous registers for short regset write")
Cc: James Hogan <james.hogan@mips.com>
Cc: Paul Burton <Paul.Burton@mips.com>
Cc: Alex Smith <alex@alex-smith.me.uk>
Cc: Dave Martin <Dave.Martin@arm.com>
Cc: linux-mips@linux-mips.org
Cc: linux-kernel@vger.kernel.org
Patchwork: https://patchwork.linux-mips.org/patch/17929/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 arch/mips/kernel/ptrace.c |    1 +
 1 file changed, 1 insertion(+)

--- a/arch/mips/kernel/ptrace.c
+++ b/arch/mips/kernel/ptrace.c
@@ -467,6 +467,7 @@ static int fpr_get_msa(struct task_struc
 	u64 fpr_val;
 	int err;
 
+	BUILD_BUG_ON(sizeof(fpr_val) != sizeof(elf_fpreg_t));
 	for (i = 0; i < NUM_FPU_REGS; i++) {
 		fpr_val = get_fpr64(&target->thread.fpu.fpr[i], 0);
 		err = user_regset_copyout(pos, count, kbuf, ubuf,


Patches currently in stable-queue which might be from macro@mips.com are

queue-4.4/mips-consistently-handle-buffer-counter-with-ptrace_setregset.patch
queue-4.4/mips-disallow-outsized-ptrace_setregset-nt_prfpreg-regset-accesses.patch
queue-4.4/mips-guard-against-any-partial-write-attempt-with-ptrace_setregset.patch
queue-4.4/mips-also-verify-sizeof-elf_fpreg_t-with-ptrace_setregset.patch
queue-4.4/mips-factor-out-nt_prfpreg-regset-access-helpers.patch
queue-4.4/mips-validate-pr_set_fp_mode-prctl-2-requests-against-the-abi-of-the-task.patch
queue-4.4/mips-fix-an-fcsr-access-api-regression-with-nt_prfpreg-and-msa.patch