Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933794AbaFTDdc (ORCPT ); Thu, 19 Jun 2014 23:33:32 -0400 Received: from mail-qc0-f179.google.com ([209.85.216.179]:56826 "EHLO mail-qc0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756143AbaFTDda (ORCPT ); Thu, 19 Jun 2014 23:33:30 -0400 Date: Thu, 19 Jun 2014 23:33:27 -0400 (EDT) From: Nicolas Pitre To: Laura Abbott cc: Geert Uytterhoeven , Grant Likely , Rob Herring , devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: Re: [PATCHv2] of: Check for phys_addr_t overflows in early_init_dt_add_memory_arch In-Reply-To: <1403234018-10942-1-git-send-email-lauraa@codeaurora.org> Message-ID: References: <1403234018-10942-1-git-send-email-lauraa@codeaurora.org> User-Agent: Alpine 2.11 (LFD 23 2013-08-11) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, 19 Jun 2014, Laura Abbott wrote: > The common early_init_dt_add_memory_arch takes the base and size > of a memory region as u64 types. The function never checks if > the base and size can actually fit in a phys_addr_t which may > be smaller than 64-bits. This may result in incorrect memory > being passed to memblock_add if the memory falls outside the > range of phys_addr_t. Add range checks for the base and size if > phys_addr_t is smaller than u64. > > Reported-by: Geert Uytterhoeven > Tested-by: Geert Uytterhoeven > Signed-off-by: Laura Abbott Acked-by: Nicolas Pitre > --- > v2: Switched to sizeof(phys_addr_t) < sizeof(u64) instead of macros. > Sending to right e-mails/mailing lists this time. > > drivers/of/fdt.c | 15 +++++++++++++++ > 1 file changed, 15 insertions(+) > > diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c > index c4cddf0..b777d8f 100644 > --- a/drivers/of/fdt.c > +++ b/drivers/of/fdt.c > @@ -880,6 +880,21 @@ void __init __weak early_init_dt_add_memory_arch(u64 base, u64 size) > const u64 phys_offset = __pa(PAGE_OFFSET); > base &= PAGE_MASK; > size &= PAGE_MASK; > + > + if (sizeof(phys_addr_t) < sizeof(u64)) { > + if (base > ULONG_MAX) { > + pr_warning("Ignoring memory block 0x%llx - 0x%llx\n", > + base, base + size); > + return; > + } > + > + if (base + size > ULONG_MAX) { > + pr_warning("Ignoring memory range 0x%lx - 0x%llx\n", > + ULONG_MAX, base + size); > + size = ULONG_MAX - base; > + } > + } > + > if (base + size < phys_offset) { > pr_warning("Ignoring memory block 0x%llx - 0x%llx\n", > base, base + size); > -- > The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, > hosted by The Linux Foundation > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/