Re: [PATCH V2 8/9 linux-next] udf: propagate udf_get_filename() errors

[Jan Kara]

 On Wed 08-04-15 21:23:58, Fabian Frederick wrote:
> -Return udf_get_filename() error from udf_readdir()
> -Return -ENOMEM from udf_find_entry() when unable to allocate
> fname and udf_get_filename() error
> -udf_find_entry() callsites are also updated:
> udf_lookup(), udf_rmdir(), udf_unlink() and udf_rename()
> 
> Suggested-by: Jan Kara <jack@xxxxxxx>
> Signed-off-by: Fabian Frederick <fabf@xxxxxxxxx>
  Thanks. I've merged this patch with slight modification -
udf_find_entry() should return -EIO instead of -EINVAL in all the cases.
I've also folded the documentation of udf_find_entry() into this patch.
Attached is the result.

								Honza
> ---
> V2:
> 	-Don't set error in udf_readdir()
> 	-Improve code flow
> 	-Merge if(nfi) if (!inode) in udf_rename()
> 
>  fs/udf/namei.c | 70 ++++++++++++++++++++++++++++++++++++++++++----------------
>  1 file changed, 51 insertions(+), 19 deletions(-)
> 
> diff --git a/fs/udf/namei.c b/fs/udf/namei.c
> index dd648b7..891c067 100644
> --- a/fs/udf/namei.c
> +++ b/fs/udf/namei.c
> @@ -167,8 +167,11 @@ static struct fileIdentDesc *udf_find_entry(struct inode *dir,
>  	fibh->soffset = fibh->eoffset = f_pos & (sb->s_blocksize - 1);
>  	if (dinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
>  		if (inode_bmap(dir, f_pos >> sb->s_blocksize_bits, &epos,
> -		    &eloc, &elen, &offset) != (EXT_RECORDED_ALLOCATED >> 30))
> +		    &eloc, &elen, &offset) != (EXT_RECORDED_ALLOCATED >> 30)) {
> +			fi = ERR_PTR(-EINVAL);
>  			goto out_err;
> +		}
> +
>  		block = udf_get_lb_pblock(sb, &eloc, offset);
>  		if ((++offset << sb->s_blocksize_bits) < elen) {
>  			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
> @@ -179,19 +182,25 @@ static struct fileIdentDesc *udf_find_entry(struct inode *dir,
>  			offset = 0;
>  
>  		fibh->sbh = fibh->ebh = udf_tread(sb, block);
> -		if (!fibh->sbh)
> +		if (!fibh->sbh) {
> +			fi = ERR_PTR(-EINVAL);
>  			goto out_err;
> +		}
>  	}
>  
>  	fname = kmalloc(UDF_NAME_LEN, GFP_NOFS);
> -	if (!fname)
> +	if (!fname) {
> +		fi = ERR_PTR(-ENOMEM);
>  		goto out_err;
> +	}
>  
>  	while (f_pos < size) {
>  		fi = udf_fileident_read(dir, &f_pos, fibh, cfi, &epos, &eloc,
>  					&elen, &offset);
> -		if (!fi)
> +		if (!fi) {
> +			fi = ERR_PTR(-EINVAL);
>  			goto out_err;
> +		}
>  
>  		liu = le16_to_cpu(cfi->lengthOfImpUse);
>  		lfi = cfi->lengthFileIdent;
> @@ -234,13 +243,18 @@ static struct fileIdentDesc *udf_find_entry(struct inode *dir,
>  			continue;
>  
>  		flen = udf_get_filename(sb, nameptr, lfi, fname, UDF_NAME_LEN);
> +		if (flen < 0) {
> +			fi = ERR_PTR(flen);
> +			goto out_err;
> +		}
> +
>  		if ((flen >= 0) && udf_match(flen, fname, child->len,
>  					    child->name))
>  			goto out_ok;
>  	}
>  
> -out_err:
>  	fi = NULL;
> +out_err:
>  	if (fibh->sbh != fibh->ebh)
>  		brelse(fibh->ebh);
>  	brelse(fibh->sbh);
> @@ -257,6 +271,7 @@ static struct dentry *udf_lookup(struct inode *dir, struct dentry *dentry,
>  	struct inode *inode = NULL;
>  	struct fileIdentDesc cfi;
>  	struct udf_fileident_bh fibh;
> +	struct fileIdentDesc *fi;
>  
>  	if (dentry->d_name.len > UDF_NAME_LEN - 2)
>  		return ERR_PTR(-ENAMETOOLONG);
> @@ -276,7 +291,11 @@ static struct dentry *udf_lookup(struct inode *dir, struct dentry *dentry,
>  	} else
>  #endif /* UDF_RECOVERY */
>  
> -	if (udf_find_entry(dir, &dentry->d_name, &fibh, &cfi)) {
> +	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
> +	if (IS_ERR(fi))
> +		return ERR_CAST(fi);
> +
> +	if (fi) {
>  		struct kernel_lb_addr loc;
>  
>  		if (fibh.sbh != fibh.ebh)
> @@ -774,8 +793,11 @@ static int udf_rmdir(struct inode *dir, struct dentry *dentry)
>  
>  	retval = -ENOENT;
>  	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
> -	if (!fi)
> +	if (IS_ERR_OR_NULL(fi)) {
> +		if (fi)
> +			retval = PTR_ERR(fi);
>  		goto out;
> +	}
>  
>  	retval = -EIO;
>  	tloc = lelb_to_cpu(cfi.icb.extLocation);
> @@ -817,8 +839,12 @@ static int udf_unlink(struct inode *dir, struct dentry *dentry)
>  
>  	retval = -ENOENT;
>  	fi = udf_find_entry(dir, &dentry->d_name, &fibh, &cfi);
> -	if (!fi)
> +
> +	if (IS_ERR_OR_NULL(fi)) {
> +		if (fi)
> +			retval = PTR_ERR(fi);
>  		goto out;
> +	}
>  
>  	retval = -EIO;
>  	tloc = lelb_to_cpu(cfi.icb.extLocation);
> @@ -1047,24 +1073,30 @@ static int udf_rename(struct inode *old_dir, struct dentry *old_dentry,
>  	struct udf_inode_info *old_iinfo = UDF_I(old_inode);
>  
>  	ofi = udf_find_entry(old_dir, &old_dentry->d_name, &ofibh, &ocfi);
> -	if (ofi) {
> -		if (ofibh.sbh != ofibh.ebh)
> -			brelse(ofibh.ebh);
> -		brelse(ofibh.sbh);
> +	if (IS_ERR(ofi)) {
> +		retval = PTR_ERR(ofi);
> +		goto end_rename;
>  	}
> +
> +	if (ofibh.sbh != ofibh.ebh)
> +		brelse(ofibh.ebh);
> +
> +	brelse(ofibh.sbh);
>  	tloc = lelb_to_cpu(ocfi.icb.extLocation);
>  	if (!ofi || udf_get_lb_pblock(old_dir->i_sb, &tloc, 0)
>  	    != old_inode->i_ino)
>  		goto end_rename;
>  
>  	nfi = udf_find_entry(new_dir, &new_dentry->d_name, &nfibh, &ncfi);
> -	if (nfi) {
> -		if (!new_inode) {
> -			if (nfibh.sbh != nfibh.ebh)
> -				brelse(nfibh.ebh);
> -			brelse(nfibh.sbh);
> -			nfi = NULL;
> -		}
> +	if (IS_ERR(nfi)) {
> +		retval = PTR_ERR(nfi);
> +		goto end_rename;
> +	}
> +	if (nfi && !new_inode) {
> +		if (nfibh.sbh != nfibh.ebh)
> +			brelse(nfibh.ebh);
> +		brelse(nfibh.sbh);
> +		nfi = NULL;
>  	}
>  	if (S_ISDIR(old_inode->i_mode)) {
>  		int offset = udf_ext0_offset(old_inode);
> -- 
> 1.9.1
> 
-- 
Jan Kara <jack@xxxxxxx>
SUSE Labs, CR