From: Kees Cook <keescook@chromium.org>
To: kernel test robot <lkp@intel.com>,
Mirko Lindner <mlindner@marvell.com>,
Stephen Hemminger <stephen@networkplumber.org>
Cc: oe-kbuild-all@lists.linux.dev, linux-kernel@vger.kernel.org,
"Gustavo A. R. Silva" <gustavoars@kernel.org>,
linux-hardening@vger.kernel.org
Subject: Re: include/linux/dma-mapping.h:416:36: warning: array subscript i is outside array bounds of 'dma_addr_t[0]' {aka 'long long unsigned int[]'}
Date: Wed, 20 Sep 2023 09:09:33 -0700 [thread overview]
Message-ID: <202309200904.CEED70DA33@keescook> (raw)
In-Reply-To: <202309191958.UBw1cjXk-lkp@intel.com>
On Tue, Sep 19, 2023 at 07:27:26PM +0800, kernel test robot wrote:
> tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
> head: 2cf0f715623872823a72e451243bbf555d10d032
> commit: df8fc4e934c12b906d08050d7779f292b9c5c6b5 kbuild: Enable -fstrict-flex-arrays=3
> date: 4 months ago
> config: loongarch-allmodconfig (https://download.01.org/0day-ci/archive/20230919/202309191958.UBw1cjXk-lkp@intel.com/config)
> compiler: loongarch64-linux-gcc (GCC) 13.2.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20230919/202309191958.UBw1cjXk-lkp@intel.com/reproduce)
>
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202309191958.UBw1cjXk-lkp@intel.com/
>
> All warnings (new ones prefixed by >>):
>
> In file included from include/linux/skbuff.h:28,
> from include/net/net_namespace.h:43,
> from include/linux/netdevice.h:38,
> from drivers/net/ethernet/marvell/sky2.c:18:
> drivers/net/ethernet/marvell/sky2.c: In function 'sky2_rx_unmap_skb':
> >> include/linux/dma-mapping.h:416:36: warning: array subscript i is outside array bounds of 'dma_addr_t[0]' {aka 'long long unsigned int[]'} [-Warray-bounds=]
> 416 | #define dma_unmap_page(d, a, s, r) dma_unmap_page_attrs(d, a, s, r, 0)
> | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> drivers/net/ethernet/marvell/sky2.c:1257:17: note: in expansion of macro 'dma_unmap_page'
> 1257 | dma_unmap_page(&pdev->dev, re->frag_addr[i],
> | ^~~~~~~~~~~~~~
> In file included from drivers/net/ethernet/marvell/sky2.c:41:
> drivers/net/ethernet/marvell/sky2.h:2198:25: note: while referencing 'frag_addr'
> 2198 | dma_addr_t frag_addr[ETH_JUMBO_MTU >> PAGE_SHIFT];
> | ^~~~~~~~~
The .config has:
CONFIG_PAGE_SIZE_16KB=y
which makes PAGE_SHIFT == 14
#ifdef CONFIG_PAGE_SIZE_16KB
#define PAGE_SHIFT 14
ETH_JUMBO_MTU is:
#define ETH_JUMBO_MTU 9000
which forces "ETH_JUMBO_MTU >> PAGE_SHIFT" to be 0.
I think the right fix would be:
dma_addr_t frag_addr[ETH_JUMBO_MTU >> PAGE_SHIFT ?: 1]
Thoughts?
-Kees
--
Kees Cook
next prev parent reply other threads:[~2023-09-20 16:09 UTC|newest]
Thread overview: 4+ messages / expand[flat|nested] mbox.gz Atom feed top
2023-09-19 11:27 include/linux/dma-mapping.h:416:36: warning: array subscript i is outside array bounds of 'dma_addr_t[0]' {aka 'long long unsigned int[]'} kernel test robot
2023-09-20 16:09 ` Kees Cook [this message]
2023-09-20 17:29 ` Stephen Hemminger
2023-09-20 20:16 ` Kees Cook
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=202309200904.CEED70DA33@keescook \
--to=keescook@chromium.org \
--cc=gustavoars@kernel.org \
--cc=linux-hardening@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=lkp@intel.com \
--cc=mlindner@marvell.com \
--cc=oe-kbuild-all@lists.linux.dev \
--cc=stephen@networkplumber.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.