mirror of
https://mirrors.bfsu.edu.cn/git/linux.git
synced 2024-12-06 02:24:14 +08:00
b490bdd630
Large (> 1 TiB) UDF filesystems appear subject to several problems when mounted on 64-bit systems: * readdir() can fail on a directory containing File Identifiers residing above 0x7FFFFFFF. This manifests as a 'ls' command failing with EIO. * FIBMAP on a file block located above 0x7FFFFFFF can return a negative value. The low 32 bits are correct, but applications that don't mask the high 32 bits of the result can perform incorrectly. Per suggestion by Jan Kara, introduce a udf_pblk_t type for representation of UDF block addresses. Ultimately, all driver functions that manipulate UDF block addresses should use this type; for now, deployment is limited to functions with actual or potential sign extension issues. Changes to udf_readdir() and udf_block_map() address the issues noted above; other changes address potential similar issues uncovered during audit of the driver code. Signed-off-by: Steven J. Magnani <steve@digidescorp.com> Signed-off-by: Jan Kara <jack@suse.cz>
210 lines
5.2 KiB
C
210 lines
5.2 KiB
C
/*
|
|
* dir.c
|
|
*
|
|
* PURPOSE
|
|
* Directory 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
|
|
*
|
|
* HISTORY
|
|
*
|
|
* 10/05/98 dgb Split directory operations into its own file
|
|
* Implemented directory reads via do_udf_readdir
|
|
* 10/06/98 Made directory operations work!
|
|
* 11/17/98 Rewrote directory to support ICBTAG_FLAG_AD_LONG
|
|
* 11/25/98 blf Rewrote directory handling (readdir+lookup) to support reading
|
|
* across blocks.
|
|
* 12/12/98 Split out the lookup code to namei.c. bulk of directory
|
|
* code now in directory.c:udf_fileident_read.
|
|
*/
|
|
|
|
#include "udfdecl.h"
|
|
|
|
#include <linux/string.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/mm.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/bio.h>
|
|
|
|
#include "udf_i.h"
|
|
#include "udf_sb.h"
|
|
|
|
|
|
static int udf_readdir(struct file *file, struct dir_context *ctx)
|
|
{
|
|
struct inode *dir = file_inode(file);
|
|
struct udf_inode_info *iinfo = UDF_I(dir);
|
|
struct udf_fileident_bh fibh = { .sbh = NULL, .ebh = NULL};
|
|
struct fileIdentDesc *fi = NULL;
|
|
struct fileIdentDesc cfi;
|
|
udf_pblk_t block, iblock;
|
|
loff_t nf_pos;
|
|
int flen;
|
|
unsigned char *fname = NULL, *copy_name = NULL;
|
|
unsigned char *nameptr;
|
|
uint16_t liu;
|
|
uint8_t lfi;
|
|
loff_t size = udf_ext0_offset(dir) + dir->i_size;
|
|
struct buffer_head *tmp, *bha[16];
|
|
struct kernel_lb_addr eloc;
|
|
uint32_t elen;
|
|
sector_t offset;
|
|
int i, num, ret = 0;
|
|
struct extent_position epos = { NULL, 0, {0, 0} };
|
|
struct super_block *sb = dir->i_sb;
|
|
|
|
if (ctx->pos == 0) {
|
|
if (!dir_emit_dot(file, ctx))
|
|
return 0;
|
|
ctx->pos = 1;
|
|
}
|
|
nf_pos = (ctx->pos - 1) << 2;
|
|
if (nf_pos >= size)
|
|
goto out;
|
|
|
|
fname = kmalloc(UDF_NAME_LEN, GFP_NOFS);
|
|
if (!fname) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
|
|
if (nf_pos == 0)
|
|
nf_pos = udf_ext0_offset(dir);
|
|
|
|
fibh.soffset = fibh.eoffset = nf_pos & (sb->s_blocksize - 1);
|
|
if (iinfo->i_alloc_type != ICBTAG_FLAG_AD_IN_ICB) {
|
|
if (inode_bmap(dir, nf_pos >> sb->s_blocksize_bits,
|
|
&epos, &eloc, &elen, &offset)
|
|
!= (EXT_RECORDED_ALLOCATED >> 30)) {
|
|
ret = -ENOENT;
|
|
goto out;
|
|
}
|
|
block = udf_get_lb_pblock(sb, &eloc, offset);
|
|
if ((++offset << sb->s_blocksize_bits) < elen) {
|
|
if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_SHORT)
|
|
epos.offset -= sizeof(struct short_ad);
|
|
else if (iinfo->i_alloc_type ==
|
|
ICBTAG_FLAG_AD_LONG)
|
|
epos.offset -= sizeof(struct long_ad);
|
|
} else {
|
|
offset = 0;
|
|
}
|
|
|
|
if (!(fibh.sbh = fibh.ebh = udf_tread(sb, block))) {
|
|
ret = -EIO;
|
|
goto out;
|
|
}
|
|
|
|
if (!(offset & ((16 >> (sb->s_blocksize_bits - 9)) - 1))) {
|
|
i = 16 >> (sb->s_blocksize_bits - 9);
|
|
if (i + offset > (elen >> sb->s_blocksize_bits))
|
|
i = (elen >> sb->s_blocksize_bits) - offset;
|
|
for (num = 0; i > 0; i--) {
|
|
block = udf_get_lb_pblock(sb, &eloc, offset + i);
|
|
tmp = udf_tgetblk(sb, block);
|
|
if (tmp && !buffer_uptodate(tmp) && !buffer_locked(tmp))
|
|
bha[num++] = tmp;
|
|
else
|
|
brelse(tmp);
|
|
}
|
|
if (num) {
|
|
ll_rw_block(REQ_OP_READ, REQ_RAHEAD, num, bha);
|
|
for (i = 0; i < num; i++)
|
|
brelse(bha[i]);
|
|
}
|
|
}
|
|
}
|
|
|
|
while (nf_pos < size) {
|
|
struct kernel_lb_addr tloc;
|
|
|
|
ctx->pos = (nf_pos >> 2) + 1;
|
|
|
|
fi = udf_fileident_read(dir, &nf_pos, &fibh, &cfi, &epos, &eloc,
|
|
&elen, &offset);
|
|
if (!fi)
|
|
goto out;
|
|
|
|
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 = (char *)(fibh.ebh->b_data + poffset - lfi);
|
|
} else {
|
|
if (!copy_name) {
|
|
copy_name = kmalloc(UDF_NAME_LEN,
|
|
GFP_NOFS);
|
|
if (!copy_name) {
|
|
ret = -ENOMEM;
|
|
goto out;
|
|
}
|
|
}
|
|
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) {
|
|
if (!dir_emit_dotdot(file, ctx))
|
|
goto out;
|
|
continue;
|
|
}
|
|
|
|
flen = udf_get_filename(sb, nameptr, lfi, fname, UDF_NAME_LEN);
|
|
if (flen < 0)
|
|
continue;
|
|
|
|
tloc = lelb_to_cpu(cfi.icb.extLocation);
|
|
iblock = udf_get_lb_pblock(sb, &tloc, 0);
|
|
if (!dir_emit(ctx, fname, flen, iblock, DT_UNKNOWN))
|
|
goto out;
|
|
} /* end while */
|
|
|
|
ctx->pos = (nf_pos >> 2) + 1;
|
|
|
|
out:
|
|
if (fibh.sbh != fibh.ebh)
|
|
brelse(fibh.ebh);
|
|
brelse(fibh.sbh);
|
|
brelse(epos.bh);
|
|
kfree(fname);
|
|
kfree(copy_name);
|
|
|
|
return ret;
|
|
}
|
|
|
|
/* readdir and lookup functions */
|
|
const struct file_operations udf_dir_operations = {
|
|
.llseek = generic_file_llseek,
|
|
.read = generic_read_dir,
|
|
.iterate_shared = udf_readdir,
|
|
.unlocked_ioctl = udf_ioctl,
|
|
.fsync = generic_file_fsync,
|
|
};
|