This is a note to let you know that I've just added the patch titled s390/kernel: fix ptrace peek/poke for floating point registers to the 4.3-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: s390-kernel-fix-ptrace-peek-poke-for-floating-point-registers.patch and it can be found in the queue-4.3 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 55a423b6f105fa323168f15f4bb67f23b21da44e Mon Sep 17 00:00:00 2001 From: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Date: Tue, 27 Oct 2015 13:13:38 +0100 Subject: s390/kernel: fix ptrace peek/poke for floating point registers From: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> commit 55a423b6f105fa323168f15f4bb67f23b21da44e upstream. git commit 155e839a814834a3b4b31e729f4716e59d3d2dd4 "s390/kernel: dynamically allocate FP register save area" introduced a regression in regard to ptrace. If the vector register extension is not present or unused the ptrace peek of a floating pointer register return incorrect data and the ptrace poke to a floating pointer register overwrites the task structure starting at task->thread.fpu.fprs. Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/s390/kernel/ptrace.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/arch/s390/kernel/ptrace.c +++ b/arch/s390/kernel/ptrace.c @@ -244,7 +244,7 @@ static unsigned long __peek_user(struct ((addr_t) child->thread.fpu.vxrs + 2*offset); else tmp = *(addr_t *) - ((addr_t) &child->thread.fpu.fprs + offset); + ((addr_t) child->thread.fpu.fprs + offset); } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) { /* @@ -388,7 +388,7 @@ static int __poke_user(struct task_struc child->thread.fpu.vxrs + 2*offset) = data; else *(addr_t *)((addr_t) - &child->thread.fpu.fprs + offset) = data; + child->thread.fpu.fprs + offset) = data; } else if (addr < (addr_t) (&dummy->regs.per_info + 1)) { /* @@ -622,7 +622,7 @@ static u32 __peek_user_compat(struct tas ((addr_t) child->thread.fpu.vxrs + 2*offset); else tmp = *(__u32 *) - ((addr_t) &child->thread.fpu.fprs + offset); + ((addr_t) child->thread.fpu.fprs + offset); } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) { /* @@ -747,7 +747,7 @@ static int __poke_user_compat(struct tas child->thread.fpu.vxrs + 2*offset) = tmp; else *(__u32 *)((addr_t) - &child->thread.fpu.fprs + offset) = tmp; + child->thread.fpu.fprs + offset) = tmp; } else if (addr < (addr_t) (&dummy32->regs.per_info + 1)) { /* Patches currently in stable-queue which might be from schwidefsky@xxxxxxxxxx are queue-4.3/s390-kernel-fix-ptrace-peek-poke-for-floating-point-registers.patch queue-4.3/s390-pci-reshuffle-struct-used-to-write-debug-data.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