[U-Boot] [PATCH v2] cmd: usb_mass_storage: add protection for block_dev

[Marek Vasut]

On 09/26/2018 01:04 PM, Patrick Delaunay wrote:
> solve data abort for the command "ums 0 ubi 0"
> because result of case blk_get_device_part_str() result is OK
> but with block_dev = 0 when CONFIG_CMD_UBIFS is activate and
> ubi volume is mounted

I don't quite understand the commit message, can you reword it?

Also, when is this ever called with block_dev == NULL ? What's the
condition to trigger this and why ?

> Signed-off-by: Patrick Delaunay <patrick.delaunay at st.com>
> ---
> I check and the issue is still present on U-Boot v2018.09,
> on my board stm32mp1 (with NAND device and UBI volume):
> 
> STM32MP> ubi part UBI
> STM32MP> ubifsmount ubi0:boot
> STM32MP> ums 0 ubi 0
> data abort
> pc : [<ffc60abc>]	   lr : [<ffc60ab3>]
> reloc pc : [<c0110abc>]	   lr : [<c0110ab3>]
> sp : fdc3e460  ip : fdc3e518	 fp : fdcf06a8
> r10: fdcf06b8  r9 : fdc4eed8	 r8 : 00000000
> r7 : ffce3d84  r6 : fdcf0740	 r5 : fdcf0740  r4 : ffce3d88
> r3 : 00000000  r2 : 00000000	 r1 : 0000003a  r0 : 00000000
> Flags: nZCv  IRQs off  FIQs off  Mode SVC_32
> Code: f04f4628 9b06fd2a bf082800 0800f04f (f5b3695b) Resetting CPU ...
> 
> Even If the command is invalid (ums not allowed on ubi device),
> the data abort can be avoid by this patch.
> 
> 
> Changes in v2:
>     - Rebase on master branch
> 
>  cmd/usb_mass_storage.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/cmd/usb_mass_storage.c b/cmd/usb_mass_storage.c
> index 26b41b4c4..a3a338c 100644
> --- a/cmd/usb_mass_storage.c
> +++ b/cmd/usb_mass_storage.c
> @@ -85,7 +85,7 @@ static int ums_init(const char *devtype, const char *devnums_part_str)
>  			partnum = 0;
>  
>  		/* f_mass_storage.c assumes SECTOR_SIZE sectors */
> -		if (block_dev->blksz != SECTOR_SIZE)
> +		if (!block_dev || block_dev->blksz != SECTOR_SIZE)
>  			goto cleanup;
>  
>  		ums_new = realloc(ums, (ums_count + 1) * sizeof(*ums));
> 


-- 
Best regards,
Marek Vasut