From: Long Li <longli@microsoft.com>
To: Erick Archer <erick.archer@outlook.com>,
Ajay Sharma <sharmaajay@microsoft.com>,
KY Srinivasan <kys@microsoft.com>,
Haiyang Zhang <haiyangz@microsoft.com>,
Wei Liu <wei.liu@kernel.org>, Dexuan Cui <decui@microsoft.com>,
"David S. Miller" <davem@davemloft.net>,
Eric Dumazet <edumazet@google.com>,
Jakub Kicinski <kuba@kernel.org>, Paolo Abeni <pabeni@redhat.com>,
Kees Cook <keescook@chromium.org>,
"Gustavo A. R. Silva" <gustavoars@kernel.org>,
Nathan Chancellor <nathan@kernel.org>,
Nick Desaulniers <ndesaulniers@google.com>,
Bill Wendling <morbo@google.com>,
Justin Stitt <justinstitt@google.com>,
Jason Gunthorpe <jgg@ziepe.ca>, Leon Romanovsky <leon@kernel.org>,
Shradha Gupta <shradhagupta@linux.microsoft.com>,
Konstantin Taranov <kotaranov@microsoft.com>
Cc: "linux-rdma@vger.kernel.org" <linux-rdma@vger.kernel.org>,
"linux-hyperv@vger.kernel.org" <linux-hyperv@vger.kernel.org>,
"netdev@vger.kernel.org" <netdev@vger.kernel.org>,
"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
"linux-hardening@vger.kernel.org"
<linux-hardening@vger.kernel.org>,
"llvm@lists.linux.dev" <llvm@lists.linux.dev>
Subject: RE: [PATCH v3 2/3] RDMA/mana_ib: Prefer struct_size over open coded arithmetic
Date: Mon, 8 Apr 2024 19:42:13 +0000 [thread overview]
Message-ID: <SJ1PR21MB3457CFCEF273664F3342A9A4CE002@SJ1PR21MB3457.namprd21.prod.outlook.com> (raw)
In-Reply-To: <AS8PR02MB72375EB06EE1A84A67BE722E8B022@AS8PR02MB7237.eurprd02.prod.outlook.com>
> Subject: [PATCH v3 2/3] RDMA/mana_ib: Prefer struct_size over open coded
> arithmetic
>
> This is an effort to get rid of all multiplications from allocation functions in order to
> prevent integer overflows [1][2].
>
> As the "req" variable is a pointer to "struct mana_cfg_rx_steer_req_v2"
> and this structure ends in a flexible array:
>
> struct mana_cfg_rx_steer_req_v2 {
> [...]
> mana_handle_t indir_tab[] __counted_by(num_indir_entries); };
>
> the preferred way in the kernel is to use the struct_size() helper to do the
> arithmetic instead of the calculation "size + size * count" in the kzalloc() function.
>
> Moreover, use the "offsetof" helper to get the indirect table offset instead of the
> "sizeof" operator and avoid the open-coded arithmetic in pointers using the new
> flex member. This new structure member also allow us to remove the
> "req_indir_tab" variable since it is no longer needed.
>
> This way, the code is more readable and safer.
>
> This code was detected with the help of Coccinelle, and audited and modified
> manually.
>
> Link:
> https://www.ker/
> nel.org%2Fdoc%2Fhtml%2Flatest%2Fprocess%2Fdeprecated.html%23open-
> coded-arithmetic-in-allocator-
> arguments&data=05%7C02%7Clongli%40microsoft.com%7Cfcf2a410393a429633
> ca08dc56506b01%7C72f988bf86f141af91ab2d7cd011db47%7C1%7C0%7C63848
> 0150654917952%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQI
> joiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C0%7C%7C%7C&sdata=2zSek
> zsyXsS1s9xw%2FwaSEl3h4s6AeiykFG4KiJLzXOc%3D&reserved=0 [1]
> Link:
> https://github.co/
> m%2FKSPP%2Flinux%2Fissues%2F160&data=05%7C02%7Clongli%40microsoft.co
> m%7Cfcf2a410393a429633ca08dc56506b01%7C72f988bf86f141af91ab2d7cd01
> 1db47%7C1%7C0%7C638480150654924997%7CUnknown%7CTWFpbGZsb3d8ey
> JWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C
> 0%7C%7C%7C&sdata=4pzQWVWVcIaeS07VgXY1I6%2FS%2FEFejUD4qv1D2Ouwf
> pA%3D&reserved=0 [2]
> Signed-off-by: Erick Archer <erick.archer@outlook.com>
Reviewed-by: Long Li <longli@microsoft.com>
next prev parent reply other threads:[~2024-04-08 19:42 UTC|newest]
Thread overview: 9+ messages / expand[flat|nested] mbox.gz Atom feed top
[not found] <20240406142337.16241-1-erick.archer@outlook.com>
2024-04-06 14:23 ` [PATCH v3 1/3] net: mana: Add flex array to struct mana_cfg_rx_steer_req_v2 Erick Archer
2024-04-08 19:42 ` Long Li
2024-04-08 21:34 ` Justin Stitt
2024-04-08 21:43 ` Justin Stitt
2024-04-06 14:23 ` [PATCH v3 2/3] RDMA/mana_ib: Prefer struct_size over open coded arithmetic Erick Archer
2024-04-08 19:42 ` Long Li [this message]
2024-04-08 21:38 ` Justin Stitt
2024-04-06 14:23 ` [PATCH v3 3/3] net: mana: Avoid " Erick Archer
2024-04-08 21:45 ` Justin Stitt
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=SJ1PR21MB3457CFCEF273664F3342A9A4CE002@SJ1PR21MB3457.namprd21.prod.outlook.com \
--to=longli@microsoft.com \
--cc=davem@davemloft.net \
--cc=decui@microsoft.com \
--cc=edumazet@google.com \
--cc=erick.archer@outlook.com \
--cc=gustavoars@kernel.org \
--cc=haiyangz@microsoft.com \
--cc=jgg@ziepe.ca \
--cc=justinstitt@google.com \
--cc=keescook@chromium.org \
--cc=kotaranov@microsoft.com \
--cc=kuba@kernel.org \
--cc=kys@microsoft.com \
--cc=leon@kernel.org \
--cc=linux-hardening@vger.kernel.org \
--cc=linux-hyperv@vger.kernel.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-rdma@vger.kernel.org \
--cc=llvm@lists.linux.dev \
--cc=morbo@google.com \
--cc=nathan@kernel.org \
--cc=ndesaulniers@google.com \
--cc=netdev@vger.kernel.org \
--cc=pabeni@redhat.com \
--cc=sharmaajay@microsoft.com \
--cc=shradhagupta@linux.microsoft.com \
--cc=wei.liu@kernel.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 a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).