From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Simek Subject: Re: [PATCH 9/9] serial: xuartps: Fix out-of-bounds access through DT alias Date: Tue, 20 Feb 2018 11:22:05 +0100 Message-ID: References: <1519119624-1268-1-git-send-email-geert+renesas@glider.be> <1519119624-1268-10-git-send-email-geert+renesas@glider.be> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1519119624-1268-10-git-send-email-geert+renesas@glider.be> Content-Language: en-US List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-snps-arc" Errors-To: linux-snps-arc-bounces+gla-linux-snps-arc=m.gmane.org@lists.infradead.org To: Geert Uytterhoeven , Greg Kroah-Hartman Cc: devicetree@vger.kernel.org, Barry Song , Vineet Gupta , Michal Simek , linux-kernel@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-serial@vger.kernel.org, Jiri Slaby , linux-snps-arc@lists.infradead.org, linux-arm-kernel@lists.infradead.org List-Id: devicetree@vger.kernel.org On 20.2.2018 10:40, Geert Uytterhoeven wrote: > The cdns_uart_port[] array is indexed using a value derived from the > "serialN" alias in DT, which may lead to an out-of-bounds access. > > Fix this by adding a range check. > > Fixes: 1f118c02a1819856 ("serial: xuartps: Fix out-of-bounds access through DT alias") I didn't find this sha1 - patch name is this one. > Signed-off-by: Geert Uytterhoeven > --- > drivers/tty/serial/xilinx_uartps.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c > index b9b2bc76bcac606c..abcb4d09a2d866d0 100644 > --- a/drivers/tty/serial/xilinx_uartps.c > +++ b/drivers/tty/serial/xilinx_uartps.c > @@ -1110,7 +1110,7 @@ static struct uart_port *cdns_uart_get_port(int id) > struct uart_port *port; > > /* Try the given port id if failed use default method */ > - if (cdns_uart_port[id].mapbase != 0) { > + if (id < CDNS_UART_NR_PORTS && cdns_uart_port[id].mapbase != 0) { > /* Find the next unused port */ > for (id = 0; id < CDNS_UART_NR_PORTS; id++) > if (cdns_uart_port[id].mapbase == 0) > Below should be better fix for this driver. Thanks, Michal diff --git a/drivers/tty/serial/xilinx_uartps.c b/drivers/tty/serial/xilinx_uartps.c index b9b2bc76bcac..b77c6477ed93 100644 --- a/drivers/tty/serial/xilinx_uartps.c +++ b/drivers/tty/serial/xilinx_uartps.c @@ -1109,6 +1109,9 @@ static struct uart_port *cdns_uart_get_port(int id) { struct uart_port *port; + if (id >= CDNS_UART_NR_PORTS) + return NULL; + /* Try the given port id if failed use default method */ if (cdns_uart_port[id].mapbase != 0) { /* Find the next unused port */ @@ -1117,9 +1120,6 @@ static struct uart_port *cdns_uart_get_port(int id) break; } - if (id >= CDNS_UART_NR_PORTS) - return NULL; - port = &cdns_uart_port[id]; /* At this point, we've got an empty uart_port struct, initialize it */