[PATCH 2/4] lib: utils/serial: Initialize platform_uart_data to zero

[Jessica Clarke]

On 18 Jul 2022, at 18:20, Andrew Jones <ajones at ventanamicro.com> wrote:
> 
> While it doesn't look like there are any current cases of using
> uninitialized data, let's zero all the UART data members to be
> safe. Zero may not actually be better than a random number in
> some cases, so all structure members should still be validated
> before use, but at least zero is usually easier to debug than
> some random stack garbage...

If fdt_parse_foo_uart_node leaves the platform_uart_data uninitialised
(at least, parts that matter) then that seems like a bug to me. This
just masks such bugs from any kind of sanitiser...

Jess

> Signed-off-by: Andrew Jones <ajones at ventanamicro.com>
> ---
> lib/utils/serial/fdt_serial_gaisler.c       | 2 +-
> lib/utils/serial/fdt_serial_shakti.c        | 2 +-
> lib/utils/serial/fdt_serial_sifive.c        | 2 +-
> lib/utils/serial/fdt_serial_uart8250.c      | 2 +-
> lib/utils/serial/fdt_serial_xlnx_uartlite.c | 2 +-
> platform/fpga/openpiton/platform.c          | 2 +-
> 6 files changed, 6 insertions(+), 6 deletions(-)
> 
> diff --git a/lib/utils/serial/fdt_serial_gaisler.c b/lib/utils/serial/fdt_serial_gaisler.c
> index 9a9f9a8b7962..74988e34bcd8 100644
> --- a/lib/utils/serial/fdt_serial_gaisler.c
> +++ b/lib/utils/serial/fdt_serial_gaisler.c
> @@ -15,7 +15,7 @@ static int serial_gaisler_init(void *fdt, int nodeoff,
> 			       const struct fdt_match *match)
> {
> 	int rc;
> -	struct platform_uart_data uart;
> +	struct platform_uart_data uart = { 0 };
> 
> 	rc = fdt_parse_gaisler_uart_node(fdt, nodeoff, &uart);
> 	if (rc)
> diff --git a/lib/utils/serial/fdt_serial_shakti.c b/lib/utils/serial/fdt_serial_shakti.c
> index 4f91419ef53c..0e056303dbb5 100644
> --- a/lib/utils/serial/fdt_serial_shakti.c
> +++ b/lib/utils/serial/fdt_serial_shakti.c
> @@ -13,7 +13,7 @@ static int serial_shakti_init(void *fdt, int nodeoff,
> 				const struct fdt_match *match)
> {
> 	int rc;
> -	struct platform_uart_data uart;
> +	struct platform_uart_data uart = { 0 };
> 
> 	rc = fdt_parse_shakti_uart_node(fdt, nodeoff, &uart);
> 	if (rc)
> diff --git a/lib/utils/serial/fdt_serial_sifive.c b/lib/utils/serial/fdt_serial_sifive.c
> index f4c833c1573d..3ca10913eee3 100644
> --- a/lib/utils/serial/fdt_serial_sifive.c
> +++ b/lib/utils/serial/fdt_serial_sifive.c
> @@ -15,7 +15,7 @@ static int serial_sifive_init(void *fdt, int nodeoff,
> 				const struct fdt_match *match)
> {
> 	int rc;
> -	struct platform_uart_data uart;
> +	struct platform_uart_data uart = { 0 };
> 
> 	rc = fdt_parse_sifive_uart_node(fdt, nodeoff, &uart);
> 	if (rc)
> diff --git a/lib/utils/serial/fdt_serial_uart8250.c b/lib/utils/serial/fdt_serial_uart8250.c
> index 544b7416de42..0b95f2d9e44e 100644
> --- a/lib/utils/serial/fdt_serial_uart8250.c
> +++ b/lib/utils/serial/fdt_serial_uart8250.c
> @@ -15,7 +15,7 @@ static int serial_uart8250_init(void *fdt, int nodeoff,
> 				const struct fdt_match *match)
> {
> 	int rc;
> -	struct platform_uart_data uart;
> +	struct platform_uart_data uart = { 0 };
> 
> 	rc = fdt_parse_uart8250_node(fdt, nodeoff, &uart);
> 	if (rc)
> diff --git a/lib/utils/serial/fdt_serial_xlnx_uartlite.c b/lib/utils/serial/fdt_serial_xlnx_uartlite.c
> index 466e16e82d8c..9f04aea3673b 100644
> --- a/lib/utils/serial/fdt_serial_xlnx_uartlite.c
> +++ b/lib/utils/serial/fdt_serial_xlnx_uartlite.c
> @@ -15,7 +15,7 @@ static int serial_xlnx_uartlite_init(void *fdt, int nodeoff,
> 				const struct fdt_match *match)
> {
> 	int rc;
> -	struct platform_uart_data uart;
> +	struct platform_uart_data uart = { 0 };
> 
> 	rc = fdt_parse_xlnx_uartlite_node(fdt, nodeoff, &uart);
> 	if (rc)
> diff --git a/platform/fpga/openpiton/platform.c b/platform/fpga/openpiton/platform.c
> index 7ca21236bfef..5ff7d200aba9 100644
> --- a/platform/fpga/openpiton/platform.c
> +++ b/platform/fpga/openpiton/platform.c
> @@ -69,7 +69,7 @@ static struct aclint_mtimer_data mtimer = {
> static int openpiton_early_init(bool cold_boot)
> {
> 	void *fdt;
> -	struct platform_uart_data uart_data;
> +	struct platform_uart_data uart_data = { 0 };
> 	struct plic_data plic_data;
> 	unsigned long aclint_freq;
> 	uint64_t clint_addr;
> -- 
> 2.36.1
> 
> 
> -- 
> opensbi mailing list
> opensbi at lists.infradead.org
> http://lists.infradead.org/mailman/listinfo/opensbi