Release 4.10 fs/udf/namei.c

/*
 * namei.c
 *
 * PURPOSE
 *      Inode name handling routines for the OSTA-UDF(tm) filesystem.
 *
 * COPYRIGHT
 *      This file is distributed under the terms of the GNU General Public
 *      License (GPL). Copies of the GPL can be obtained from:
 *              ftp://prep.ai.mit.edu/pub/gnu/GPL
 *      Each contributing author retains all rights to their own work.
 *
 *  (C) 1998-2004 Ben Fennema
 *  (C) 1999-2000 Stelias Computing Inc
 *
 * HISTORY
 *
 *  12/12/98 blf  Created. Split out the lookup code from dir.c
 *  04/19/99 blf  link, mknod, symlink support
 */

#include "udfdecl.h"

#include "udf_i.h"
#include "udf_sb.h"
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/crc-itu-t.h>
#include <linux/exportfs.h>



static inline int udf_match(int len1, const unsigned char *name1, int len2,
			    const unsigned char *name2)
{
	if (len1 != len2)
		return 0;

	return !memcmp(name1, name2, len1);
}

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int udf_write_fi(struct inode *inode, struct fileIdentDesc *cfi,
		 struct fileIdentDesc *sfi, struct udf_fileident_bh *fibh,
		 uint8_t *impuse, uint8_t *fileident)
{
	uint16_t crclen = fibh->eoffset - fibh->soffset - sizeof(struct tag);
	uint16_t crc;
	int offset;
	uint16_t liu = le16_to_cpu(cfi->lengthOfImpUse);
	uint8_t lfi = cfi->lengthFileIdent;
	int padlen = fibh->eoffset - fibh->soffset - liu - lfi -
		sizeof(struct fileIdentDesc);
	int adinicb = 0;

	if (UDF_I(inode)->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB)
		adinicb = 1;

	offset = fibh->soffset + sizeof(struct fileIdentDesc);

	if (impuse) {
		if (adinicb || (offset + liu < 0)) {
			memcpy((uint8_t *)sfi->impUse, impuse, liu);
		} else if (offset >= 0) {
			memcpy(fibh->ebh->b_data + offset, impuse, liu);
		} else {
			memcpy((uint8_t *)sfi->impUse, impuse, -offset);
			memcpy(fibh->ebh->b_data, impuse - offset,
				liu + offset);
		}
	}

	offset += liu;

	if (fileident) {
		if (adinicb || (offset + lfi < 0)) {
			memcpy((uint8_t *)sfi->fileIdent + liu, fileident, lfi);
		} else if (offset >= 0) {
			memcpy(fibh->ebh->b_data + offset, fileident, lfi);
		} else {
			memcpy((uint8_t *)sfi->fileIdent + liu, fileident,
				-offset);
			memcpy(fibh->ebh->b_data, fileident - offset,
				lfi + offset);
		}
	}

	offset += lfi;

	if (adinicb || (offset + padlen < 0)) {
		memset((uint8_t *)sfi->padding + liu + lfi, 0x00, padlen);
	} else if (offset >= 0) {
		memset(fibh->ebh->b_data + offset, 0x00, padlen);
	} else {
		memset((uint8_t *)sfi->padding + liu + lfi, 0x00, -offset);
		memset(fibh->ebh->b_data, 0x00, padlen + offset);
	}

	crc = crc_itu_t(0, (uint8_t *)cfi + sizeof(struct tag),
		      sizeof(struct fileIdentDesc) - sizeof(struct tag));

	if (fibh->sbh == fibh->ebh) {
		crc = crc_itu_t(crc, (uint8_t *)sfi->impUse,
			      crclen + sizeof(struct tag) -
			      sizeof(struct fileIdentDesc));
	} else if (sizeof(struct fileIdentDesc) >= -fibh->soffset) {
		crc = crc_itu_t(crc, fibh->ebh->b_data +
					sizeof(struct fileIdentDesc) +
					fibh->soffset,
			      crclen + sizeof(struct tag) -
					sizeof(struct fileIdentDesc));
	} else {
		crc = crc_itu_t(crc, (uint8_t *)sfi->impUse,
			      -fibh->soffset - sizeof(struct fileIdentDesc));
		crc = crc_itu_t(crc, fibh->ebh->b_data, fibh->eoffset);
	}

	cfi->descTag.descCRC = cpu_to_le16(crc);
	cfi->descTag.descCRCLength = cpu_to_le16(crclen);
	cfi->descTag.tagChecksum = udf_tag_checksum(&cfi->descTag);

	if (adinicb || (sizeof(struct fileIdentDesc) <= -fibh->soffset)) {
		memcpy((uint8_t *)sfi, (uint8_t *)cfi,
			sizeof(struct fileIdentDesc));
	} else {
		memcpy((uint8_t *)sfi, (uint8_t *)cfi, -fibh->soffset);
		memcpy(fibh->ebh->b_data, (uint8_t *)cfi - fibh->soffset,
		       sizeof(struct fileIdentDesc) + fibh->soffset);
	}

	if (adinicb) {
		mark_inode_dirty(inode);
	} else {
		if (fibh->sbh != fibh->ebh)
			mark_buffer_dirty_inode(fibh->ebh, inode);
		mark_buffer_dirty_inode(fibh->sbh, inode);
	}
	return 0;
}

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ben fennema
ben fennema
78
10.17%
2
18.18%
cyrill gorcunov
cyrill gorcunov
20
2.61%
1
9.09%
bob copeland
bob copeland
15
1.96%
1
9.09%
linus torvalds
linus torvalds
11
1.43%
1
9.09%
marcin slusarz
marcin slusarz
10
1.30%
2
18.18%
pekka j enberg
pekka j enberg
5
0.65%
1
9.09%
al viro
al viro
1
0.13%
1
9.09%
Total
767
100.00%
11
100.00%

/**
 * udf_find_entry - find entry in given directory.
 *
 * @dir:        directory inode to search in
 * @child:      qstr of the name
 * @fibh:       buffer head / inode with file identifier descriptor we found
 * @cfi:        found file identifier descriptor with given name
 *
 * This function searches in the directory @dir for a file name @child. When
 * found, @fibh points to the buffer head(s) (bh is NULL for in ICB
 * directories) containing the file identifier descriptor (FID). In that case
 * the function returns pointer to the FID in the buffer or inode - but note
 * that FID may be split among two buffers (blocks) so accessing it via that
 * pointer isn't easily possible. This pointer can be used only as an iterator
 * for other directory manipulation functions. For inspection of the FID @cfi
 * can be used - the found FID is copied there.
 *
 * Returns pointer to FID, NULL when nothing found, or error code.
 */


static struct fileIdentDesc *udf_find_entry(struct inode *dir,
					    const struct qstr *child,
					    struct udf_fileident_bh *fibh,
					    struct fileIdentDesc *cfi)
{
	struct fileIdentDesc *fi = NULL;
	loff_t f_pos;
	int block, flen;
	unsigned char *fname = NULL, *copy_name = NULL;
	unsigned char *nameptr;
	uint8_t lfi;
	uint16_t liu;
	loff_t size;
	struct kernel_lb_addr eloc;
	uint32_t elen;
	sector_t offset;
	struct extent_position epos = {};
	struct udf_inode_info *dinfo = UDF_I(dir);
	int isdotdot = child->len == 2 &&
		child->name[0] == '.' && child->name[1] == '.';
	struct super_block *sb = dir->i_sb;

	size = udf_ext0_offset(dir) + dir->i_size;
	f_pos = udf_ext0_offset(dir);

	fibh->sbh = fibh->ebh = NULL;
	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)) {
			fi = ERR_PTR(-EIO);
			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)
				epos.offset -= sizeof(struct short_ad);
			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
				epos.offset -= sizeof(struct long_ad);
		} else
			offset = 0;

		fibh->sbh = fibh->ebh = udf_tread(sb, block);
		if (!fibh->sbh) {
			fi = ERR_PTR(-EIO);
			goto out_err;
		}
	}

	fname = kmalloc(UDF_NAME_LEN, GFP_NOFS);
	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) {
			fi = ERR_PTR(-EIO);
			goto out_err;
		}

		liu = le16_to_cpu(cfi->lengthOfImpUse);
		lfi = cfi->lengthFileIdent;

		if (fibh->sbh == fibh->ebh) {
			nameptr = fi->fileIdent + liu;
		} else {
			int poffset;	/* Unpaded ending offset */

			poffset = fibh->soffset + sizeof(struct fileIdentDesc) +
					liu + lfi;

			if (poffset >= lfi)
				nameptr = (uint8_t *)(fibh->ebh->b_data +
						      poffset - lfi);
			else {
				if (!copy_name) {
					copy_name = kmalloc(UDF_NAME_LEN,
							    GFP_NOFS);
					if (!copy_name) {
						fi = ERR_PTR(-ENOMEM);
						goto out_err;
					}
				}
				nameptr = copy_name;
				memcpy(nameptr, fi->fileIdent + liu,
					lfi - poffset);
				memcpy(nameptr + lfi - poffset,
					fibh->ebh->b_data, poffset);
			}
		}

		if ((cfi->fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNDELETE))
				continue;
		}

		if ((cfi->fileCharacteristics & FID_FILE_CHAR_HIDDEN) != 0) {
			if (!UDF_QUERY_FLAG(sb, UDF_FLAG_UNHIDE))
				continue;
		}

		if ((cfi->fileCharacteristics & FID_FILE_CHAR_PARENT) &&
		    isdotdot)
			goto out_ok;

		if (!lfi)
			continue;

		flen = udf_get_filename(sb, nameptr, lfi, fname, UDF_NAME_LEN);
		if (flen < 0) {
			fi = ERR_PTR(flen);
			goto out_err;
		}

		if (udf_match(flen, fname, child->len, child->name))
			goto out_ok;
	}

	fi = NULL;
out_err:
	if (fibh->sbh != fibh->ebh)
		brelse(fibh->ebh);
	brelse(fibh->sbh);
out_ok:
	brelse(epos.bh);
	kfree(fname);
	kfree(copy_name);

	return fi;
}

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136
18.23%
7
24.14%
fabian frederick
fabian frederick
59
7.91%
2
6.90%
rasmus rohde
rasmus rohde
36
4.83%
1
3.45%
marcin slusarz
marcin slusarz
28
3.75%
3
10.34%
ben fennema
ben fennema
25
3.35%
2
6.90%
andrew morton
andrew morton
20
2.68%
1
3.45%
al viro
al viro
11
1.47%
3
10.34%
zaur kambarov
zaur kambarov
11
1.47%
1
3.45%
pekka j enberg
pekka j enberg
4
0.54%
2
6.90%
jesper juhl
jesper juhl
3
0.40%
1
3.45%
cyrill gorcunov
cyrill gorcunov
1
0.13%
1
3.45%
Total
746
100.00%
29
100.00%



static struct dentry *udf_lookup(struct inode *dir, struct dentry *dentry,
				 unsigned int flags)
{
	struct inode *inode = NULL;
	struct fileIdentDesc cfi;
	struct udf_fileident_bh fibh;
	struct fileIdentDesc *fi;

	if (dentry->d_name.len > UDF_NAME_LEN)
		return ERR_PTR(-ENAMETOOLONG);

#ifdef UDF_RECOVERY
	/* temporary shorthand for specifying files by inode number */
	if (!strncmp(dentry->d_name.name, ".B=", 3)) {
		struct kernel_lb_addr lb = {
			.logicalBlockNum = 0,
			.partitionReferenceNum =
				simple_strtoul(dentry->d_name.name + 3,
						NULL, 0),
                };
		inode = udf_iget(dir->i_sb, lb);
		if (IS_ERR(inode))
			return inode;
	} else
#endif /* UDF_RECOVERY */

	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)
			brelse(fibh.ebh);
		brelse(fibh.sbh);

		loc = lelb_to_cpu(cfi.icb.extLocation);
		inode = udf_iget(dir->i_sb, &loc);
		if (IS_ERR(inode))
			return ERR_CAST(inode);
	}

	return d_splice_alias(inode, dentry);
}

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25
10.25%
1
6.67%
pekka j enberg
pekka j enberg
17
6.97%
2
13.33%
cyrill gorcunov
cyrill gorcunov
14
5.74%
1
6.67%
jan kara
jan kara
11
4.51%
2
13.33%
al viro
al viro
7
2.87%
3
20.00%
rasmus rohde
rasmus rohde
4
1.64%
1
6.67%
trond myklebust
trond myklebust
1
0.41%
1
6.67%
ben fennema
ben fennema
1
0.41%
1
6.67%
Total
244
100.00%
15
100.00%



static struct fileIdentDesc *udf_add_entry(struct inode *dir,
					   struct dentry *dentry,
					   struct udf_fileident_bh *fibh,
					   struct fileIdentDesc *cfi, int *err)
{
	struct super_block *sb = dir->i_sb;
	struct fileIdentDesc *fi = NULL;
	unsigned char *name = NULL;
	int namelen;
	loff_t f_pos;
	loff_t size = udf_ext0_offset(dir) + dir->i_size;
	int nfidlen;
	uint8_t lfi;
	uint16_t liu;
	int block;
	struct kernel_lb_addr eloc;
	uint32_t elen = 0;
	sector_t offset;
	struct extent_position epos = {};
	struct udf_inode_info *dinfo;

	fibh->sbh = fibh->ebh = NULL;
	name = kmalloc(UDF_NAME_LEN_CS0, GFP_NOFS);
	if (!name) {
		*err = -ENOMEM;
		goto out_err;
	}

	if (dentry) {
		if (!dentry->d_name.len) {
			*err = -EINVAL;
			goto out_err;
		}
		namelen = udf_put_filename(sb, dentry->d_name.name,
					   dentry->d_name.len,
					   name, UDF_NAME_LEN_CS0);
		if (!namelen) {
			*err = -ENAMETOOLONG;
			goto out_err;
		}
	} else {
		namelen = 0;
	}

	nfidlen = (sizeof(struct fileIdentDesc) + namelen + 3) & ~3;

	f_pos = udf_ext0_offset(dir);

	fibh->soffset = fibh->eoffset = f_pos & (dir->i_sb->s_blocksize - 1);
	dinfo = UDF_I(dir);
	if (dinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
		if (inode_bmap(dir, f_pos >> dir->i_sb->s_blocksize_bits, &epos,
		    &eloc, &elen, &offset) != (EXT_RECORDED_ALLOCATED >> 30)) {
			block = udf_get_lb_pblock(dir->i_sb,
					&dinfo->i_location, 0);
			fibh->soffset = fibh->eoffset = sb->s_blocksize;
			goto add;
		}
		block = udf_get_lb_pblock(dir->i_sb, &eloc, offset);
		if ((++offset << dir->i_sb->s_blocksize_bits) < elen) {
			if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
				epos.offset -= sizeof(struct short_ad);
			else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
				epos.offset -= sizeof(struct long_ad);
		} else
			offset = 0;

		fibh->sbh = fibh->ebh = udf_tread(dir->i_sb, block);
		if (!fibh->sbh) {
			*err = -EIO;
			goto out_err;
		}

		block = dinfo->i_location.logicalBlockNum;
	}

	while (f_pos < size) {
		fi = udf_fileident_read(dir, &f_pos, fibh, cfi, &epos, &eloc,
					&elen, &offset);

		if (!fi) {
			*err = -EIO;
			goto out_err;
		}

		liu = le16_to_cpu(cfi->lengthOfImpUse);
		lfi = cfi->lengthFileIdent;

		if ((cfi->fileCharacteristics & FID_FILE_CHAR_DELETED) != 0) {
			if (((sizeof(struct fileIdentDesc) +
					liu + lfi + 3) & ~3) == nfidlen) {
				cfi->descTag.tagSerialNum = cpu_to_le16(1);
				cfi->fileVersionNum = cpu_to_le16(1);
				cfi->fileCharacteristics = 0;
				cfi->lengthFileIdent = namelen;
				cfi->lengthOfImpUse = cpu_to_le16(0);
				if (!udf_write_fi(dir, cfi, fi, fibh, NULL,
						  name))
					goto out_ok;
				else {
					*err = -EIO;
					goto out_err;
				}
			}
		}
	}

add:
	f_pos += nfidlen;

	if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB &&
	    sb->s_blocksize - fibh->eoffset < nfidlen) {
		brelse(epos.bh);
		epos.bh = NULL;
		fibh->soffset -= udf_ext0_offset(dir);
		fibh->eoffset -= udf_ext0_offset(dir);
		f_pos -= udf_ext0_offset(dir);
		if (fibh->sbh != fibh->ebh)
			brelse(fibh->ebh);
		brelse(fibh->sbh);
		fibh->sbh = fibh->ebh =
				udf_expand_dir_adinicb(dir, &block, err);
		if (!fibh->sbh)
			goto out_err;
		epos.block = dinfo->i_location;
		epos.offset = udf_file_entry_alloc_offset(dir);
		/* Load extent udf_expand_dir_adinicb() has created */
		udf_current_aext(dir, &epos, &eloc, &elen, 1);
	}

	/* Entry fits into current block? */
	if (sb->s_blocksize - fibh->eoffset >= nfidlen) {
		fibh->soffset = fibh->eoffset;
		fibh->eoffset += nfidlen;
		if (fibh->sbh != fibh->ebh) {
			brelse(fibh->sbh);
			fibh->sbh = fibh->ebh;
		}

		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
			block = dinfo->i_location.logicalBlockNum;
			fi = (struct fileIdentDesc *)
					(dinfo->i_ext.i_data +
					 fibh->soffset -
					 udf_ext0_offset(dir) +
					 dinfo->i_lenEAttr);
		} else {
			block = eloc.logicalBlockNum +
					((elen - 1) >>
						dir->i_sb->s_blocksize_bits);
			fi = (struct fileIdentDesc *)
				(fibh->sbh->b_data + fibh->soffset);
		}
	} else {
		/* Round up last extent in the file */
		elen = (elen + sb->s_blocksize - 1) & ~(sb->s_blocksize - 1);
		if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
			epos.offset -= sizeof(struct short_ad);
		else if (dinfo->i_alloc_type == ICBTAG_FLAG_AD_LONG)
			epos.offset -= sizeof(struct long_ad);
		udf_write_aext(dir, &epos, &eloc, elen, 1);
		dinfo->i_lenExtents = (dinfo->i_lenExtents + sb->s_blocksize
					- 1) & ~(sb->s_blocksize - 1);

		fibh->soffset = fibh->eoffset - sb->s_blocksize;
		fibh->eoffset += nfidlen - sb->s_blocksize;
		if (fibh->sbh != fibh->ebh) {
			brelse(fibh->sbh);
			fibh->sbh = fibh->ebh;
		}

		block = eloc.logicalBlockNum + ((elen - 1) >>
						dir->i_sb->s_blocksize_bits);
		fibh->ebh = udf_bread(dir,
				f_pos >> dir->i_sb->s_blocksize_bits, 1, err);
		if (!fibh->ebh)
			goto out_err;
		/* Extents could have been merged, invalidate our position */
		brelse(epos.bh);
		epos.bh = NULL;
		epos.block = dinfo->i_location;
		epos.offset = udf_file_entry_alloc_offset(dir);

		if (!fibh->soffset) {
			/* Find the freshly allocated block */
			while (udf_next_aext(dir, &epos, &eloc, &elen, 1) ==
				(EXT_RECORDED_ALLOCATED >> 30))
				;
			block = eloc.logicalBlockNum + ((elen - 1) >>
					dir->i_sb->s_blocksize_bits);
			brelse(fibh->sbh);
			fibh->sbh = fibh->ebh;
			fi = (struct fileIdentDesc *)(fibh->sbh->b_data);
		} else {
			fi = (struct fileIdentDesc *)
				(fibh->sbh->b_data + sb->s_blocksize +
					fibh->soffset);
		}
	}

	memset(cfi, 0, sizeof(struct fileIdentDesc));
	if (UDF_SB(sb)->s_udfrev >= 0x0200)
		udf_new_tag((char *)cfi, TAG_IDENT_FID, 3, 1, block,
			    sizeof(struct tag));
	else
		udf_new_tag((char *)cfi, TAG_IDENT_FID, 2, 1, block,
			    sizeof(struct tag));
	cfi->fileVersionNum = cpu_to_le16(1);
	cfi->lengthFileIdent = namelen;
	cfi->lengthOfImpUse = cpu_to_le16(0);
	if (!udf_write_fi(dir, cfi, fi, fibh, NULL, name)) {
		dir->