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

[Patrick DELAUNAY]

Hi Marek and Lucaz

I have found this old patch:  See https://lists.denx.de/pipermail/u-boot/2017-October/309716.html

On 10/18/2017 10:22 PM, Marek Vasut-3 wrote:

>On 10/18/2017 06:27 PM, Tom Rini wrote: 
>> On Wed, Oct 18, 2017 at 04:03:21PM +0200, 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 
>>> 
>>> Signed-off-by: Patrick Delaunay <[hidden email]> 

>This is UMS, so Lukasz ... please review _thoroughly_ , as I suspect 
>there might be some weird underlying issue . 

>>> --- 
>>> 
>>>  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 cfeecb7..c0563ca 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)); 
>> 
>> Adding in Marek..
>>
>-- 
>Best regards, 
>Marek Vasut

Do you think that this patch is needed.
I check and the issue is still present on U-Boot v2018.09 :

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, I think that data abort should be avoid.

Regards

Patrick