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[198.145.64.163]) by smtp.gmail.com with ESMTPSA id b190sm808833pgc.91.2021.08.18.14.51.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 18 Aug 2021 14:51:07 -0700 (PDT) Date: Wed, 18 Aug 2021 14:51:06 -0700 From: Kees Cook To: Marc Kleine-Budde Cc: linux-kernel@vger.kernel.org, "Gustavo A. R. Silva" , Arnd Bergmann , Ayush Sawal , Vinay Kumar Yadav , Rohit Maheshwari , Herbert Xu , "David S. Miller" , Kalle Valo , Jakub Kicinski , Stanislaw Gruszka , Luca Coelho , "James E.J. Bottomley" , "Martin K. Petersen" , Alexei Starovoitov , Daniel Borkmann , Andrii Nakryiko , Martin KaFai Lau , Song Liu , Yonghong Song , John Fastabend , KP Singh , Johannes Berg , Mordechay Goodstein , Lee Jones , Wolfgang Grandegger , Arunachalam Santhanam , Vincent Mailhol , Mikulas Patocka , linux-crypto@vger.kernel.org, ath10k@lists.infradead.org, linux-wireless@vger.kernel.org, netdev@vger.kernel.org, linux-scsi@vger.kernel.org, linux-can@vger.kernel.org, bpf@vger.kernel.org, clang-built-linux@googlegroups.com, linux-hardening@vger.kernel.org Subject: Re: [PATCH 2/5] treewide: Replace open-coded flex arrays in unions Message-ID: <202108181448.9C13CE9@keescook> References: <20210818081118.1667663-1-keescook@chromium.org> <20210818081118.1667663-3-keescook@chromium.org> <20210818095635.tm42ctkm6aydjr6g@pengutronix.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210818095635.tm42ctkm6aydjr6g@pengutronix.de> Precedence: bulk List-ID: X-Mailing-List: linux-can@vger.kernel.org On Wed, Aug 18, 2021 at 11:56:35AM +0200, Marc Kleine-Budde wrote: > On 18.08.2021 01:11:15, Kees Cook wrote: > > diff --git a/drivers/net/can/usb/etas_es58x/es581_4.h b/drivers/net/can/usb/etas_es58x/es581_4.h > > index 4bc60a6df697..8657145dc2a9 100644 > > --- a/drivers/net/can/usb/etas_es58x/es581_4.h > > +++ b/drivers/net/can/usb/etas_es58x/es581_4.h > > @@ -192,7 +192,7 @@ struct es581_4_urb_cmd { > > struct es581_4_rx_cmd_ret rx_cmd_ret; > > __le64 timestamp; > > u8 rx_cmd_ret_u8; > > - u8 raw_msg[0]; > > + flex_array(u8 raw_msg); > > } __packed; > > > > __le16 reserved_for_crc16_do_not_use; > > diff --git a/drivers/net/can/usb/etas_es58x/es58x_fd.h b/drivers/net/can/usb/etas_es58x/es58x_fd.h > > index ee18a87e40c0..3053e0958132 100644 > > --- a/drivers/net/can/usb/etas_es58x/es58x_fd.h > > +++ b/drivers/net/can/usb/etas_es58x/es58x_fd.h > > @@ -228,7 +228,7 @@ struct es58x_fd_urb_cmd { > > struct es58x_fd_tx_ack_msg tx_ack_msg; > > __le64 timestamp; > > __le32 rx_cmd_ret_le32; > > - u8 raw_msg[0]; > > + flex_array(u8 raw_msg[]); > > } __packed; > > This doesn't look consistent, what's preferred? > > u8 raw_msg[0]; -> flex_array(u8 raw_msg); > - or- > -> flex_array(u8 raw_msg[]); Eek, thanks for catching that. And this helps me realize that having "flex_array" and "[]" is redundant, and the above typo would have been caught. I will fix this for v2. Thanks! -Kees -- Kees Cook