Re: [U-Boot] [PATCH] UBIFS: Change ubifsload to not read beyond the requested size

Dear Stefan Roese,

In message 1288343093-31276-1-git-send-email-sr@denx.de you wrote:

Until now ubifsload pads the destination with 0 up to a multiple of UBIFS_BLOCK_SIZE (4KiB) while reading a file to memory. This patch changes this behaviour to only read to the requested length. This is either the file length or the length/size provided as parameter to the ubifsload command.

Signed-off-by: Stefan Roese sr@denx.de

This patch makes the patch [UBIFS: Add padded size to ubifsload output] posted yesterday obsolete since we're not padding any more now.

...

• 		/*
  

• 		 * We need to buffer the data locally for the
  

• 		 * last block. This is to not pad the destination
  

• 		 * area to a multiple of UBIFS_BLOCK_SIZE.
  

• 		 */
  

• 		buff = malloc(UBIFS_BLOCK_SIZE);
  

• 		/* Read block-siez into temp buffer */
  

• 		ret = read_block(inode, buff, block, dn);
  

• 		if (last_block_size)
  

• 			dlen = last_block_size;
  

• 		else
  

• 			dlen = le32_to_cpu(dn->size);
  

How about some error handling?

malloc() can fail, and read_block() can fail as well.

• 		/* Now copy required size back to dest */
  

• 		memcpy(addr, buff, dlen);
  

• 		free(buff);
  

• 	} else {
  

• 		ret = read_block(inode, addr, block, dn);
  

• 		if (ret) {
  

• 			err = ret;
  

• 			if (err != -ENOENT)
  

• 				break;
  

or simpler:

ret = read_block(inode, addr, block, dn); if (ret != -ENOENT) { err = ret; break; }

Best regards,

Wolfgang Denk