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

[Wolfgang Denk]

Dear Stefan Roese,

In message <1288343093-31276-1-git-send-email-sr at 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 at 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

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