[U-Boot] [PATCH v3 1/5] common: introduce maximum load size

[Lukasz Majewski <l.majewski@samsung.com>]

Hi Rob,

> From: Rob Herring <robh@kernel.org>
> 
> Various commands that load images have no checks that a loaded image
> does not exceed the available RAM space and will happily continue
> overwriting u-boot or other RAM that should not be touched. Also,
> some commands such as USB DFU or fastboot need to know the maximum
> buffer size, but there is no common way to define this.
> 
> Introduce a global load_size and environment variable loadsize to
> specify the size. The default is ~0UL which is effectively unlimited.
> 
> Signed-off-by: Rob Herring <robh@kernel.org>
> ---
>  README                     |  3 +++
>  common/board_r.c           |  1 +
>  common/image.c             | 17 +++++++++++++++++
>  include/common.h           |  1 +
>  include/config_fallbacks.h |  4 ++++
>  5 files changed, 26 insertions(+)
> 
> diff --git a/README b/README
> index 39e05d3..45c0438 100644
> --- a/README
> +++ b/README
> @@ -4871,6 +4871,9 @@ List of environment variables (most likely not
> complete): loadaddr	- Default load address for commands like
> "bootp", "rarpboot", "tftpboot", "loadb" or "diskboot"
>  
> +  loadsize	- Maximum load size for commands like "bootp",
> +		  "rarpboot", "tftpboot", "loadb" or "diskboot"
> +
>    loads_echo	- see CONFIG_LOADS_ECHO
>  
>    serverip	- TFTP server IP address; needed for tftpboot
> command diff --git a/common/board_r.c b/common/board_r.c
> index 8629a65..b420f43 100644
> --- a/common/board_r.c
> +++ b/common/board_r.c
> @@ -451,6 +451,7 @@ static int initr_env(void)
>  
>  	/* Initialize from environment */
>  	load_addr = getenv_ulong("loadaddr", 16, load_addr);
> +	load_size = getenv_ulong("loadsize", 16, load_size);
>  #if defined(CONFIG_SYS_EXTBDINFO)
>  #if defined(CONFIG_405GP) || defined(CONFIG_405EP)
>  #if defined(CONFIG_I2CFAST)
> diff --git a/common/image.c b/common/image.c
> index 9c6bec5..afbf806 100644
> --- a/common/image.c
> +++ b/common/image.c
> @@ -396,6 +396,7 @@ static const image_header_t
> *image_get_ramdisk(ulong rd_addr, uint8_t
> arch, /*****************************************************************************/
> #ifndef USE_HOSTCC ulong load_addr = CONFIG_SYS_LOAD_ADDR;	/*
> Default Load Address */ +ulong load_size =
> CONFIG_SYS_LOAD_SIZE;	/* Default Load Size */ ulong
> save_addr;			/* Default Save Address */ ulong
> save_size;			/* Default Save Size (in bytes) */ 
> @@ -415,6 +416,22 @@ static int on_loadaddr(const char *name, const
> char *value, enum env_op op, }
>  U_BOOT_ENV_CALLBACK(loadaddr, on_loadaddr);
>  
> +static int on_loadsize(const char *name, const char *value, enum
> env_op op,
> +	int flags)
> +{
> +	switch (op) {
> +	case env_op_create:
> +	case env_op_overwrite:
> +		load_size = simple_strtoul(value, NULL, 16);
> +		break;
> +	default:
> +		break;
> +	}
> +
> +	return 0;
> +}
> +U_BOOT_ENV_CALLBACK(loadsize, on_loadsize);
> +
>  ulong getenv_bootm_low(void)
>  {
>  	char *s = getenv("bootm_low");
> diff --git a/include/common.h b/include/common.h
> index cbd3c9e..80f366e 100644
> --- a/include/common.h
> +++ b/include/common.h
> @@ -342,6 +342,7 @@ void flash_perror (int);
>  int	source (ulong addr, const char *fit_uname);
>  
>  extern ulong load_addr;		/* Default Load Address */
> +extern ulong load_size;		/* Default Load Size
> (maximum) */ extern ulong save_addr;		/* Default Save
> Address */ extern ulong save_size;		/* Default Save
> Size */ 
> diff --git a/include/config_fallbacks.h b/include/config_fallbacks.h
> index e6fb47b..92a36f5 100644
> --- a/include/config_fallbacks.h
> +++ b/include/config_fallbacks.h
> @@ -79,4 +79,8 @@
>  #define CONFIG_SYS_HZ		1000
>  #endif
>  
> +#ifndef CONFIG_SYS_LOAD_SIZE
> +#define CONFIG_SYS_LOAD_SIZE	(~0UL)
> +#endif
> +
>  #endif	/* __CONFIG_FALLBACKS_H */

Reviewed-by: Lukasz Majewski <l.majewski@samsung.com>

-- 
Best regards,

Lukasz Majewski

Samsung R&D Institute Poland (SRPOL) | Linux Platform Group