This is a note to let you know that I've just added the patch titled arm64/ptrace: Reject attempts to set incomplete hardware breakpoint fields 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: arm64-ptrace-reject-attempts-to-set-incomplete-hardware-breakpoint-fields.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@xxxxxxxxxxxxxxx> know about it. >From ad9e202aa1ce571b1d7fed969d06f66067f8a086 Mon Sep 17 00:00:00 2001 From: Dave Martin <Dave.Martin@xxxxxxx> Date: Wed, 18 Jan 2017 16:25:24 +0000 Subject: arm64/ptrace: Reject attempts to set incomplete hardware breakpoint fields From: Dave Martin <Dave.Martin@xxxxxxx> commit ad9e202aa1ce571b1d7fed969d06f66067f8a086 upstream. We cannot preserve partial fields for hardware breakpoints, because the values written by userspace to the hardware breakpoint registers can't subsequently be recovered intact from the hardware. So, just reject attempts to write incomplete fields with -EINVAL. Fixes: 478fcb2cdb23 ("arm64: Debugging support") Signed-off-by: Dave Martin <Dave.Martin@xxxxxxx> Acked-by: Will Deacon <Will.Deacon@xxxxxxx> Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/arm64/kernel/ptrace.c | 4 ++++ 1 file changed, 4 insertions(+) --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -450,6 +450,8 @@ static int hw_break_set(struct task_stru /* (address, ctrl) registers */ limit = regset->n * regset->size; while (count && offset < limit) { + if (count < PTRACE_HBP_ADDR_SZ) + return -EINVAL; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &addr, offset, offset + PTRACE_HBP_ADDR_SZ); if (ret) @@ -459,6 +461,8 @@ static int hw_break_set(struct task_stru return ret; offset += PTRACE_HBP_ADDR_SZ; + if (!count) + break; ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &ctrl, offset, offset + PTRACE_HBP_CTRL_SZ); if (ret) Patches currently in stable-queue which might be from Dave.Martin@xxxxxxx are queue-4.4/arm64-ptrace-preserve-previous-registers-for-short-regset-write-3.patch queue-4.4/arm64-ptrace-reject-attempts-to-set-incomplete-hardware-breakpoint-fields.patch queue-4.4/arm64-ptrace-preserve-previous-registers-for-short-regset-write-2.patch queue-4.4/arm64-ptrace-avoid-uninitialised-struct-padding-in-fpr_set.patch queue-4.4/arm64-ptrace-preserve-previous-registers-for-short-regset-write.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