linux-kernel - Re: [PATCH] of: Check for phys_addr_t overflows in early_init_dt_add_memory_arch

Open Source and information security mailing list archives

Message-ID: <CAL_JsqJW-mBb7C=ni2YLK-h9kfcAHs6b-uVJ-Zi-+MW0F_x1=Q@mail.gmail.com>
Date:	Thu, 19 Jun 2014 08:57:00 -0500
From:	Rob Herring <robherring2@...il.com>
To:	Laura Abbott <lauraa@...eaurora.org>
Cc:	Grant Likely <grant.likely@...aro.org>,
	Rob Herring <rob.herring@...xeda.com>,
	Geert Uytterhoeven <geert@...ux-m68k.org>,
	"devicetree-discuss@...ts.ozlabs.org" 
	<devicetree-discuss@...ts.ozlabs.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
	"linux-arm-kernel@...ts.infradead.org" 
	<linux-arm-kernel@...ts.infradead.org>
Subject: Re: [PATCH] of: Check for phys_addr_t overflows in early_init_dt_add_memory_arch

On Thu, Jun 19, 2014 at 12:04 AM, Laura Abbott <lauraa@...eaurora.org> 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 <geert@...ux-m68k.org>
> Signed-off-by: Laura Abbott <lauraa@...eaurora.org>
> ---
> Geert, can you drop my other patch and give this a test to see if it fixes
> your bootup problem?
>
> ---
>  drivers/of/fdt.c | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
>
> diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
> index c4cddf0..f72132c 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;
> +
> +#ifndef CONFIG_ARCH_PHYS_ADDR_T_64BIT
> +       if (base > ULONG_MAX) {

How about removing the ifdef and doing something like:

if ((base >> 32) && (sizeof(phys_addr_t) != sizeof(u64)))

> +               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;
> +       }
> +#endif
> +
>         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
>
>
> _______________________________________________
> linux-arm-kernel mailing list
> linux-arm-kernel@...ts.infradead.org
> http://lists.infradead.org/mailman/listinfo/linux-arm-kernel
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives