The patch below does not apply to the 3.18-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From c8c5a3a24d395b14447a9a89d61586a913840a3b Mon Sep 17 00:00:00 2001

From: "Maciej W. Rozycki" macro@mips.com Date: Mon, 11 Dec 2017 22:56:54 +0000 Subject: [PATCH] MIPS: Disallow outsized PTRACE_SETREGSET NT_PRFPREG regset accesses

Complement commit c23b3d1a5311 ("MIPS: ptrace: Change GP regset to use correct core dump register layout") and also reject outsized PTRACE_SETREGSET requests to the NT_PRFPREG regset, like with the NT_PRSTATUS regset.

Signed-off-by: Maciej W. Rozycki macro@mips.com Fixes: c23b3d1a5311 ("MIPS: ptrace: Change GP regset to use correct core dump register layout") 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 Cc: stable@vger.kernel.org # v3.17+ Patchwork: https://patchwork.linux-mips.org/patch/17930/ Signed-off-by: Ralf Baechle ralf@linux-mips.org

diff --git a/arch/mips/kernel/ptrace.c b/arch/mips/kernel/ptrace.c index 256908951a7c..0b23b1ad99e6 100644 --- a/arch/mips/kernel/ptrace.c +++ b/arch/mips/kernel/ptrace.c @@ -550,6 +550,9 @@ static int fpr_set(struct task_struct *target,

BUG_ON(count % sizeof(elf_fpreg_t));

+ if (pos + count > sizeof(elf_fpregset_t)) + return -EIO; + init_fp_ctx(target);

if (sizeof(target->thread.fpu.fpr[0]) == sizeof(elf_fpreg_t))