Re: [U-Boot] [PATCH] cmd_sf: Fix problem with "sf update" and unaligned length

Hi Wolfgang,

On 12.01.2015 08:17, Wolfgang Denk wrote:

...

The new code is even simpler and copies the source data into the temp buffer and now uses the temp buffer to write the complete sector. So only one SPI sector write is used now instead of 2 in the old version.

...

...

if (len != flash->sector_size) {

• /* Rewrite the original data to the end of the sector */
  

• if (spi_flash_write(flash, offset + len,
  

• 		    flash->sector_size - len, &cmp_buf[len]))
  

• 	return "write";
  

• memcpy(cmp_buf, buf, len);
  

• ptr = cmp_buf;
  

  }

Should we add a memset(buf, 0, sizeof(buf)) before the memcpy() to prevent information from earlier activities to leak?

"buf" points to the new data to be written into the flash. We're overwriting the first "len" bytes of "cmp_buf" with this data.

I don't see why we should erase anything there. Perhaps I'm missing something though.

Thanks, Stefan