On Tue 07-07-15 13:06:05, Steven J. Magnani wrote:
> For a UDF filesystem configured with an Unallocated Space Table,
> a filesystem operation that triggers an update to the table results
> in on-disk corruption that prevents remounting:
>
> udf_read_tagged: tag version 0x0000 != 0x0002 || 0x0003, block 274
>
> For example:
> 1. Create a filesystem
> $ mkudffs --media-type=hd --blocksize=512 --lvid=BUGTEST \
> --vid=BUGTEST --fsid=BUGTEST --space=unalloctable \
> /dev/mmcblk0
>
> 2. Mount it
> # mount /dev/mmcblk0 /mnt
>
> 3. Create a file
> $ echo "No corruption, please" > /mnt/new.file
>
> 4. Umount
> # umount /mnt
>
> 5. Attempt remount
> # mount /dev/mmcblk0 /mnt
>
> This appears to be a longstanding bug caused by zero-initialization of
> the Unallocated Space Entry block buffer and only partial repopulation
> of required fields before writing to disk.
>
> Commit 0adfb339fd64 ("udf: Fix unalloc space handling in udf_update_inode")
> addressed one such field, but several others are required.
>
> Signed-off-by: Steven J. Magnani <[email protected]>
So the patch looks good to me. But what kind of mkudffs are you using?
Because when I use the command you wrote into the changelog, I cannot mount
the filesystem. The kernel complains about:
UDF-fs: error (device ubdb): udf_read_inode: (ino 274) failed ident=256
mount: /dev/ubdb: can't read superblock
Now ident 256 is TAG_IDENT_FSD (file set descriptor). So apparently my
mkudffs doesn't create proper partition table with your parameters...
Honza
> ---
> diff -uprN a/fs/udf/inode.c b/fs/udf/inode.c
> --- a/fs/udf/inode.c 2015-07-06 13:42:08.861499890 -0500
> +++ b/fs/udf/inode.c 2015-07-06 13:42:18.153499469 -0500
> @@ -1652,17 +1652,9 @@ static int udf_update_inode(struct inode
> iinfo->i_ext.i_data, inode->i_sb->s_blocksize -
> sizeof(struct unallocSpaceEntry));
> use->descTag.tagIdent = cpu_to_le16(TAG_IDENT_USE);
> - use->descTag.tagLocation =
> - cpu_to_le32(iinfo->i_location.logicalBlockNum);
> - crclen = sizeof(struct unallocSpaceEntry) +
> - iinfo->i_lenAlloc - sizeof(struct tag);
> - use->descTag.descCRCLength = cpu_to_le16(crclen);
> - use->descTag.descCRC = cpu_to_le16(crc_itu_t(0, (char *)use +
> - sizeof(struct tag),
> - crclen));
> - use->descTag.tagChecksum = udf_tag_checksum(&use->descTag);
> + crclen = sizeof(struct unallocSpaceEntry);
>
> - goto out;
> + goto finish;
> }
>
> if (UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_UID_FORGET))
> @@ -1782,6 +1774,8 @@ static int udf_update_inode(struct inode
> efe->descTag.tagIdent = cpu_to_le16(TAG_IDENT_EFE);
> crclen = sizeof(struct extendedFileEntry);
> }
> +
> +finish:
> if (iinfo->i_strat4096) {
> fe->icbTag.strategyType = cpu_to_le16(4096);
> fe->icbTag.strategyParameter = cpu_to_le16(1);
> @@ -1791,7 +1785,9 @@ static int udf_update_inode(struct inode
> fe->icbTag.numEntries = cpu_to_le16(1);
> }
>
> - if (S_ISDIR(inode->i_mode))
> + if (iinfo->i_use)
> + fe->icbTag.fileType = ICBTAG_FILE_TYPE_USE;
> + else if (S_ISDIR(inode->i_mode))
> fe->icbTag.fileType = ICBTAG_FILE_TYPE_DIRECTORY;
> else if (S_ISREG(inode->i_mode))
> fe->icbTag.fileType = ICBTAG_FILE_TYPE_REGULAR;
> @@ -1828,7 +1824,6 @@ static int udf_update_inode(struct inode
> crclen));
> fe->descTag.tagChecksum = udf_tag_checksum(&fe->descTag);
>
> -out:
> set_buffer_uptodate(bh);
> unlock_buffer(bh);
>
--
Jan Kara <[email protected]>
SUSE Labs, CR
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