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linux/fs/cifs/readdir.c
Shirish Pargaonkar 76c510ad2e [CIFS] Fix possible double free if search immediately after search rewind fails 
Signed-off-by: Shirish Pargaonkar <shirishp@us.ibm.com>
Signed-off-by: Steve French <sfrench@us.ibm.com>
2008-07-24 14:48:33 +00:00

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/*
* fs/cifs/readdir.c
*
* Directory search handling
*
* Copyright (C) International Business Machines Corp., 2004, 2008
* Author(s): Steve French (sfrench@us.ibm.com)
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published
* by the Free Software Foundation; either version 2.1 of the License, or
* (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See
* the GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/stat.h>
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_unicode.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"
#include "cifsfs.h"
#ifdef CONFIG_CIFS_DEBUG2
static void dump_cifs_file_struct(struct file *file, char *label)
{
struct cifsFileInfo *cf;
if (file) {
cf = file->private_data;
if (cf == NULL) {
cFYI(1, ("empty cifs private file data"));
return;
}
if (cf->invalidHandle)
cFYI(1, ("invalid handle"));
if (cf->srch_inf.endOfSearch)
cFYI(1, ("end of search"));
if (cf->srch_inf.emptyDir)
cFYI(1, ("empty dir"));
}
}
#else
static inline void dump_cifs_file_struct(struct file *file, char *label)
{
}
#endif /* DEBUG2 */
/* Returns one if new inode created (which therefore needs to be hashed) */
/* Might check in the future if inode number changed so we can rehash inode */
static int construct_dentry(struct qstr *qstring, struct file *file,
struct inode **ptmp_inode, struct dentry **pnew_dentry)
{
struct dentry *tmp_dentry;
struct cifs_sb_info *cifs_sb;
struct cifsTconInfo *pTcon;
int rc = 0;
cFYI(1, ("For %s", qstring->name));
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
pTcon = cifs_sb->tcon;
qstring->hash = full_name_hash(qstring->name, qstring->len);
tmp_dentry = d_lookup(file->f_path.dentry, qstring);
if (tmp_dentry) {
cFYI(0, ("existing dentry with inode 0x%p",
tmp_dentry->d_inode));
*ptmp_inode = tmp_dentry->d_inode;
/* BB overwrite old name? i.e. tmp_dentry->d_name and tmp_dentry->d_name.len??*/
if (*ptmp_inode == NULL) {
*ptmp_inode = new_inode(file->f_path.dentry->d_sb);
if (*ptmp_inode == NULL)
return rc;
rc = 1;
}
if (file->f_path.dentry->d_sb->s_flags & MS_NOATIME)
(*ptmp_inode)->i_flags |= S_NOATIME | S_NOCMTIME;
} else {
tmp_dentry = d_alloc(file->f_path.dentry, qstring);
if (tmp_dentry == NULL) {
cERROR(1, ("Failed allocating dentry"));
*ptmp_inode = NULL;
return rc;
}
*ptmp_inode = new_inode(file->f_path.dentry->d_sb);
if (pTcon->nocase)
tmp_dentry->d_op = &cifs_ci_dentry_ops;
else
tmp_dentry->d_op = &cifs_dentry_ops;
if (*ptmp_inode == NULL)
return rc;
if (file->f_path.dentry->d_sb->s_flags & MS_NOATIME)
(*ptmp_inode)->i_flags |= S_NOATIME | S_NOCMTIME;
rc = 2;
}
tmp_dentry->d_time = jiffies;
*pnew_dentry = tmp_dentry;
return rc;
}
static void AdjustForTZ(struct cifsTconInfo *tcon, struct inode *inode)
{
if ((tcon) && (tcon->ses) && (tcon->ses->server)) {
inode->i_ctime.tv_sec += tcon->ses->server->timeAdj;
inode->i_mtime.tv_sec += tcon->ses->server->timeAdj;
inode->i_atime.tv_sec += tcon->ses->server->timeAdj;
}
return;
}
static void fill_in_inode(struct inode *tmp_inode, int new_buf_type,
char *buf, unsigned int *pobject_type, int isNewInode)
{
loff_t local_size;
struct timespec local_mtime;
struct cifsInodeInfo *cifsInfo = CIFS_I(tmp_inode);
struct cifs_sb_info *cifs_sb = CIFS_SB(tmp_inode->i_sb);
__u32 attr;
__u64 allocation_size;
__u64 end_of_file;
umode_t default_mode;
/* save mtime and size */
local_mtime = tmp_inode->i_mtime;
local_size = tmp_inode->i_size;
if (new_buf_type) {
FILE_DIRECTORY_INFO *pfindData = (FILE_DIRECTORY_INFO *)buf;
attr = le32_to_cpu(pfindData->ExtFileAttributes);
allocation_size = le64_to_cpu(pfindData->AllocationSize);
end_of_file = le64_to_cpu(pfindData->EndOfFile);
tmp_inode->i_atime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastAccessTime));
tmp_inode->i_mtime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastWriteTime));
tmp_inode->i_ctime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->ChangeTime));
} else { /* legacy, OS2 and DOS style */
/* struct timespec ts;*/
FIND_FILE_STANDARD_INFO *pfindData =
(FIND_FILE_STANDARD_INFO *)buf;
tmp_inode->i_mtime = cnvrtDosUnixTm(
le16_to_cpu(pfindData->LastWriteDate),
le16_to_cpu(pfindData->LastWriteTime));
tmp_inode->i_atime = cnvrtDosUnixTm(
le16_to_cpu(pfindData->LastAccessDate),
le16_to_cpu(pfindData->LastAccessTime));
tmp_inode->i_ctime = cnvrtDosUnixTm(
le16_to_cpu(pfindData->LastWriteDate),
le16_to_cpu(pfindData->LastWriteTime));
AdjustForTZ(cifs_sb->tcon, tmp_inode);
attr = le16_to_cpu(pfindData->Attributes);
allocation_size = le32_to_cpu(pfindData->AllocationSize);
end_of_file = le32_to_cpu(pfindData->DataSize);
}
/* Linux can not store file creation time unfortunately so ignore it */
cifsInfo->cifsAttrs = attr;
#ifdef CONFIG_CIFS_EXPERIMENTAL
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_CIFS_ACL) {
/* get more accurate mode via ACL - so force inode refresh */
cifsInfo->time = 0;
} else
#endif /* CONFIG_CIFS_EXPERIMENTAL */
cifsInfo->time = jiffies;
/* treat dos attribute of read-only as read-only mode bit e.g. 555? */
/* 2767 perms - indicate mandatory locking */
/* BB fill in uid and gid here? with help from winbind?
or retrieve from NTFS stream extended attribute */
if (atomic_read(&cifsInfo->inUse) == 0) {
tmp_inode->i_uid = cifs_sb->mnt_uid;
tmp_inode->i_gid = cifs_sb->mnt_gid;
}
if (attr & ATTR_DIRECTORY)
default_mode = cifs_sb->mnt_dir_mode;
else
default_mode = cifs_sb->mnt_file_mode;
/* set initial permissions */
if ((atomic_read(&cifsInfo->inUse) == 0) ||
(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DYNPERM) == 0)
tmp_inode->i_mode = default_mode;
else {
/* just reenable write bits if !ATTR_READONLY */
if ((tmp_inode->i_mode & S_IWUGO) == 0 &&
(attr & ATTR_READONLY) == 0)
tmp_inode->i_mode |= (S_IWUGO & default_mode);
tmp_inode->i_mode &= ~S_IFMT;
}
/* clear write bits if ATTR_READONLY is set */
if (attr & ATTR_READONLY)
tmp_inode->i_mode &= ~S_IWUGO;
/* set inode type */
if ((attr & ATTR_SYSTEM) &&
(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_UNX_EMUL)) {
if (end_of_file == 0) {
tmp_inode->i_mode |= S_IFIFO;
*pobject_type = DT_FIFO;
} else {
/*
* trying to get the type can be slow, so just call
* this a regular file for now, and mark for reval
*/
tmp_inode->i_mode |= S_IFREG;
*pobject_type = DT_REG;
cifsInfo->time = 0;
}
} else {
if (attr & ATTR_DIRECTORY) {
tmp_inode->i_mode |= S_IFDIR;
*pobject_type = DT_DIR;
} else {
tmp_inode->i_mode |= S_IFREG;
*pobject_type = DT_REG;
}
}
/* can not fill in nlink here as in qpathinfo version and Unx search */
if (atomic_read(&cifsInfo->inUse) == 0)
atomic_set(&cifsInfo->inUse, 1);
spin_lock(&tmp_inode->i_lock);
if (is_size_safe_to_change(cifsInfo, end_of_file)) {
/* can not safely change the file size here if the
client is writing to it due to potential races */
i_size_write(tmp_inode, end_of_file);
/* 512 bytes (2**9) is the fake blocksize that must be used */
/* for this calculation, even though the reported blocksize is larger */
tmp_inode->i_blocks = (512 - 1 + allocation_size) >> 9;
}
spin_unlock(&tmp_inode->i_lock);
if (allocation_size < end_of_file)
cFYI(1, ("May be sparse file, allocation less than file size"));
cFYI(1, ("File Size %ld and blocks %llu",
(unsigned long)tmp_inode->i_size,
(unsigned long long)tmp_inode->i_blocks));
if (S_ISREG(tmp_inode->i_mode)) {
cFYI(1, ("File inode"));
tmp_inode->i_op = &cifs_file_inode_ops;
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
tmp_inode->i_fop = &cifs_file_direct_nobrl_ops;
else
tmp_inode->i_fop = &cifs_file_direct_ops;
} else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
tmp_inode->i_fop = &cifs_file_nobrl_ops;
else
tmp_inode->i_fop = &cifs_file_ops;
if ((cifs_sb->tcon) && (cifs_sb->tcon->ses) &&
(cifs_sb->tcon->ses->server->maxBuf <
PAGE_CACHE_SIZE + MAX_CIFS_HDR_SIZE))
tmp_inode->i_data.a_ops = &cifs_addr_ops_smallbuf;
else
tmp_inode->i_data.a_ops = &cifs_addr_ops;
if (isNewInode)
return; /* No sense invalidating pages for new inode
since have not started caching readahead file
data yet */
if (timespec_equal(&tmp_inode->i_mtime, &local_mtime) &&
(local_size == tmp_inode->i_size)) {
cFYI(1, ("inode exists but unchanged"));
} else {
/* file may have changed on server */
cFYI(1, ("invalidate inode, readdir detected change"));
invalidate_remote_inode(tmp_inode);
}
} else if (S_ISDIR(tmp_inode->i_mode)) {
cFYI(1, ("Directory inode"));
tmp_inode->i_op = &cifs_dir_inode_ops;
tmp_inode->i_fop = &cifs_dir_ops;
} else if (S_ISLNK(tmp_inode->i_mode)) {
cFYI(1, ("Symbolic Link inode"));
tmp_inode->i_op = &cifs_symlink_inode_ops;
} else {
cFYI(1, ("Init special inode"));
init_special_inode(tmp_inode, tmp_inode->i_mode,
tmp_inode->i_rdev);
}
}
static void unix_fill_in_inode(struct inode *tmp_inode,
FILE_UNIX_INFO *pfindData, unsigned int *pobject_type, int isNewInode)
{
loff_t local_size;
struct timespec local_mtime;
struct cifsInodeInfo *cifsInfo = CIFS_I(tmp_inode);
struct cifs_sb_info *cifs_sb = CIFS_SB(tmp_inode->i_sb);
__u32 type = le32_to_cpu(pfindData->Type);
__u64 num_of_bytes = le64_to_cpu(pfindData->NumOfBytes);
__u64 end_of_file = le64_to_cpu(pfindData->EndOfFile);
cifsInfo->time = jiffies;
atomic_inc(&cifsInfo->inUse);
/* save mtime and size */
local_mtime = tmp_inode->i_mtime;
local_size = tmp_inode->i_size;
tmp_inode->i_atime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastAccessTime));
tmp_inode->i_mtime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastModificationTime));
tmp_inode->i_ctime =
cifs_NTtimeToUnix(le64_to_cpu(pfindData->LastStatusChange));
tmp_inode->i_mode = le64_to_cpu(pfindData->Permissions);
/* since we set the inode type below we need to mask off type
to avoid strange results if bits above were corrupt */
tmp_inode->i_mode &= ~S_IFMT;
if (type == UNIX_FILE) {
*pobject_type = DT_REG;
tmp_inode->i_mode |= S_IFREG;
} else if (type == UNIX_SYMLINK) {
*pobject_type = DT_LNK;
tmp_inode->i_mode |= S_IFLNK;
} else if (type == UNIX_DIR) {
*pobject_type = DT_DIR;
tmp_inode->i_mode |= S_IFDIR;
} else if (type == UNIX_CHARDEV) {
*pobject_type = DT_CHR;
tmp_inode->i_mode |= S_IFCHR;
tmp_inode->i_rdev = MKDEV(le64_to_cpu(pfindData->DevMajor),
le64_to_cpu(pfindData->DevMinor) & MINORMASK);
} else if (type == UNIX_BLOCKDEV) {
*pobject_type = DT_BLK;
tmp_inode->i_mode |= S_IFBLK;
tmp_inode->i_rdev = MKDEV(le64_to_cpu(pfindData->DevMajor),
le64_to_cpu(pfindData->DevMinor) & MINORMASK);
} else if (type == UNIX_FIFO) {
*pobject_type = DT_FIFO;
tmp_inode->i_mode |= S_IFIFO;
} else if (type == UNIX_SOCKET) {
*pobject_type = DT_SOCK;
tmp_inode->i_mode |= S_IFSOCK;
} else {
/* safest to just call it a file */
*pobject_type = DT_REG;
tmp_inode->i_mode |= S_IFREG;
cFYI(1, ("unknown inode type %d", type));
}
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_UID)
tmp_inode->i_uid = cifs_sb->mnt_uid;
else
tmp_inode->i_uid = le64_to_cpu(pfindData->Uid);
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_OVERR_GID)
tmp_inode->i_gid = cifs_sb->mnt_gid;
else
tmp_inode->i_gid = le64_to_cpu(pfindData->Gid);
tmp_inode->i_nlink = le64_to_cpu(pfindData->Nlinks);
spin_lock(&tmp_inode->i_lock);
if (is_size_safe_to_change(cifsInfo, end_of_file)) {
/* can not safely change the file size here if the
client is writing to it due to potential races */
i_size_write(tmp_inode, end_of_file);
/* 512 bytes (2**9) is the fake blocksize that must be used */
/* for this calculation, not the real blocksize */
tmp_inode->i_blocks = (512 - 1 + num_of_bytes) >> 9;
}
spin_unlock(&tmp_inode->i_lock);
if (S_ISREG(tmp_inode->i_mode)) {
cFYI(1, ("File inode"));
tmp_inode->i_op = &cifs_file_inode_ops;
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_DIRECT_IO) {
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
tmp_inode->i_fop = &cifs_file_direct_nobrl_ops;
else
tmp_inode->i_fop = &cifs_file_direct_ops;
} else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_NO_BRL)
tmp_inode->i_fop = &cifs_file_nobrl_ops;
else
tmp_inode->i_fop = &cifs_file_ops;
if ((cifs_sb->tcon) && (cifs_sb->tcon->ses) &&
(cifs_sb->tcon->ses->server->maxBuf <
PAGE_CACHE_SIZE + MAX_CIFS_HDR_SIZE))
tmp_inode->i_data.a_ops = &cifs_addr_ops_smallbuf;
else
tmp_inode->i_data.a_ops = &cifs_addr_ops;
if (isNewInode)
return; /* No sense invalidating pages for new inode
since we have not started caching readahead
file data for it yet */
if (timespec_equal(&tmp_inode->i_mtime, &local_mtime) &&
(local_size == tmp_inode->i_size)) {
cFYI(1, ("inode exists but unchanged"));
} else {
/* file may have changed on server */
cFYI(1, ("invalidate inode, readdir detected change"));
invalidate_remote_inode(tmp_inode);
}
} else if (S_ISDIR(tmp_inode->i_mode)) {
cFYI(1, ("Directory inode"));
tmp_inode->i_op = &cifs_dir_inode_ops;
tmp_inode->i_fop = &cifs_dir_ops;
} else if (S_ISLNK(tmp_inode->i_mode)) {
cFYI(1, ("Symbolic Link inode"));
tmp_inode->i_op = &cifs_symlink_inode_ops;
/* tmp_inode->i_fop = *//* do not need to set to anything */
} else {
cFYI(1, ("Special inode"));
init_special_inode(tmp_inode, tmp_inode->i_mode,
tmp_inode->i_rdev);
}
}
static int initiate_cifs_search(const int xid, struct file *file)
{
int rc = 0;
char *full_path;
struct cifsFileInfo *cifsFile;
struct cifs_sb_info *cifs_sb;
struct cifsTconInfo *pTcon;
if (file->private_data == NULL) {
file->private_data =
kzalloc(sizeof(struct cifsFileInfo), GFP_KERNEL);
}
if (file->private_data == NULL)
return -ENOMEM;
cifsFile = file->private_data;
cifsFile->invalidHandle = true;
cifsFile->srch_inf.endOfSearch = false;
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
if (cifs_sb == NULL)
return -EINVAL;
pTcon = cifs_sb->tcon;
if (pTcon == NULL)
return -EINVAL;
full_path = build_path_from_dentry(file->f_path.dentry);
if (full_path == NULL)
return -ENOMEM;
cFYI(1, ("Full path: %s start at: %lld", full_path, file->f_pos));
ffirst_retry:
/* test for Unix extensions */
/* but now check for them on the share/mount not on the SMB session */
/* if (pTcon->ses->capabilities & CAP_UNIX) { */
if (pTcon->unix_ext)
cifsFile->srch_inf.info_level = SMB_FIND_FILE_UNIX;
else if ((pTcon->ses->capabilities &
(CAP_NT_SMBS | CAP_NT_FIND)) == 0) {
cifsFile->srch_inf.info_level = SMB_FIND_FILE_INFO_STANDARD;
} else if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) {
cifsFile->srch_inf.info_level = SMB_FIND_FILE_ID_FULL_DIR_INFO;
} else /* not srvinos - BB fixme add check for backlevel? */ {
cifsFile->srch_inf.info_level = SMB_FIND_FILE_DIRECTORY_INFO;
}
rc = CIFSFindFirst(xid, pTcon, full_path, cifs_sb->local_nls,
&cifsFile->netfid, &cifsFile->srch_inf,
cifs_sb->mnt_cifs_flags &
CIFS_MOUNT_MAP_SPECIAL_CHR, CIFS_DIR_SEP(cifs_sb));
if (rc == 0)
cifsFile->invalidHandle = false;
if ((rc == -EOPNOTSUPP) &&
(cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
cifs_sb->mnt_cifs_flags &= ~CIFS_MOUNT_SERVER_INUM;
goto ffirst_retry;
}
kfree(full_path);
return rc;
}
/* return length of unicode string in bytes */
static int cifs_unicode_bytelen(char *str)
{
int len;
__le16 *ustr = (__le16 *)str;
for (len = 0; len <= PATH_MAX; len++) {
if (ustr[len] == 0)
return len << 1;
}
cFYI(1, ("Unicode string longer than PATH_MAX found"));
return len << 1;
}
static char *nxt_dir_entry(char *old_entry, char *end_of_smb, int level)
{
char *new_entry;
FILE_DIRECTORY_INFO *pDirInfo = (FILE_DIRECTORY_INFO *)old_entry;
if (level == SMB_FIND_FILE_INFO_STANDARD) {
FIND_FILE_STANDARD_INFO *pfData;
pfData = (FIND_FILE_STANDARD_INFO *)pDirInfo;
new_entry = old_entry + sizeof(FIND_FILE_STANDARD_INFO) +
pfData->FileNameLength;
} else
new_entry = old_entry + le32_to_cpu(pDirInfo->NextEntryOffset);
cFYI(1, ("new entry %p old entry %p", new_entry, old_entry));
/* validate that new_entry is not past end of SMB */
if (new_entry >= end_of_smb) {
cERROR(1,
("search entry %p began after end of SMB %p old entry %p",
new_entry, end_of_smb, old_entry));
return NULL;
} else if (((level == SMB_FIND_FILE_INFO_STANDARD) &&
(new_entry + sizeof(FIND_FILE_STANDARD_INFO) > end_of_smb))
|| ((level != SMB_FIND_FILE_INFO_STANDARD) &&
(new_entry + sizeof(FILE_DIRECTORY_INFO) > end_of_smb))) {
cERROR(1, ("search entry %p extends after end of SMB %p",
new_entry, end_of_smb));
return NULL;
} else
return new_entry;
}
#define UNICODE_DOT cpu_to_le16(0x2e)
/* return 0 if no match and 1 for . (current directory) and 2 for .. (parent) */
static int cifs_entry_is_dot(char *current_entry, struct cifsFileInfo *cfile)
{
int rc = 0;
char *filename = NULL;
int len = 0;
if (cfile->srch_inf.info_level == SMB_FIND_FILE_UNIX) {
FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
filename = &pFindData->FileName[0];
if (cfile->srch_inf.unicode) {
len = cifs_unicode_bytelen(filename);
} else {
/* BB should we make this strnlen of PATH_MAX? */
len = strnlen(filename, 5);
}
} else if (cfile->srch_inf.info_level == SMB_FIND_FILE_DIRECTORY_INFO) {
FILE_DIRECTORY_INFO *pFindData =
(FILE_DIRECTORY_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
} else if (cfile->srch_inf.info_level ==
SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
FILE_FULL_DIRECTORY_INFO *pFindData =
(FILE_FULL_DIRECTORY_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
} else if (cfile->srch_inf.info_level ==
SMB_FIND_FILE_ID_FULL_DIR_INFO) {
SEARCH_ID_FULL_DIR_INFO *pFindData =
(SEARCH_ID_FULL_DIR_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
} else if (cfile->srch_inf.info_level ==
SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
FILE_BOTH_DIRECTORY_INFO *pFindData =
(FILE_BOTH_DIRECTORY_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
} else if (cfile->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD) {
FIND_FILE_STANDARD_INFO *pFindData =
(FIND_FILE_STANDARD_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = pFindData->FileNameLength;
} else {
cFYI(1, ("Unknown findfirst level %d",
cfile->srch_inf.info_level));
}
if (filename) {
if (cfile->srch_inf.unicode) {
__le16 *ufilename = (__le16 *)filename;
if (len == 2) {
/* check for . */
if (ufilename[0] == UNICODE_DOT)
rc = 1;
} else if (len == 4) {
/* check for .. */
if ((ufilename[0] == UNICODE_DOT)
&& (ufilename[1] == UNICODE_DOT))
rc = 2;
}
} else /* ASCII */ {
if (len == 1) {
if (filename[0] == '.')
rc = 1;
} else if (len == 2) {
if ((filename[0] == '.') && (filename[1] == '.'))
rc = 2;
}
}
}
return rc;
}
/* Check if directory that we are searching has changed so we can decide
whether we can use the cached search results from the previous search */
static int is_dir_changed(struct file *file)
{
struct inode *inode = file->f_path.dentry->d_inode;
struct cifsInodeInfo *cifsInfo = CIFS_I(inode);
if (cifsInfo->time == 0)
return 1; /* directory was changed, perhaps due to unlink */
else
return 0;
}
/* find the corresponding entry in the search */
/* Note that the SMB server returns search entries for . and .. which
complicates logic here if we choose to parse for them and we do not
assume that they are located in the findfirst return buffer.*/
/* We start counting in the buffer with entry 2 and increment for every
entry (do not increment for . or .. entry) */
static int find_cifs_entry(const int xid, struct cifsTconInfo *pTcon,
struct file *file, char **ppCurrentEntry, int *num_to_ret)
{
int rc = 0;
int pos_in_buf = 0;
loff_t first_entry_in_buffer;
loff_t index_to_find = file->f_pos;
struct cifsFileInfo *cifsFile = file->private_data;
/* check if index in the buffer */
if ((cifsFile == NULL) || (ppCurrentEntry == NULL) ||
(num_to_ret == NULL))
return -ENOENT;
*ppCurrentEntry = NULL;
first_entry_in_buffer =
cifsFile->srch_inf.index_of_last_entry -
cifsFile->srch_inf.entries_in_buffer;
/* if first entry in buf is zero then is first buffer
in search response data which means it is likely . and ..
will be in this buffer, although some servers do not return
. and .. for the root of a drive and for those we need
to start two entries earlier */
dump_cifs_file_struct(file, "In fce ");
if (((index_to_find < cifsFile->srch_inf.index_of_last_entry) &&
is_dir_changed(file)) ||
(index_to_find < first_entry_in_buffer)) {
/* close and restart search */
cFYI(1, ("search backing up - close and restart search"));
if (!cifsFile->srch_inf.endOfSearch &&
!cifsFile->invalidHandle) {
cifsFile->invalidHandle = true;
CIFSFindClose(xid, pTcon, cifsFile->netfid);
}
if (cifsFile->srch_inf.ntwrk_buf_start) {
cFYI(1, ("freeing SMB ff cache buf on search rewind"));
if (cifsFile->srch_inf.smallBuf)
cifs_small_buf_release(cifsFile->srch_inf.
ntwrk_buf_start);
else
cifs_buf_release(cifsFile->srch_inf.
ntwrk_buf_start);
cifsFile->srch_inf.ntwrk_buf_start = NULL;
}
rc = initiate_cifs_search(xid, file);
if (rc) {
cFYI(1, ("error %d reinitiating a search on rewind",
rc));
return rc;
}
}
while ((index_to_find >= cifsFile->srch_inf.index_of_last_entry) &&
(rc == 0) && !cifsFile->srch_inf.endOfSearch) {
cFYI(1, ("calling findnext2"));
rc = CIFSFindNext(xid, pTcon, cifsFile->netfid,
&cifsFile->srch_inf);
if (rc)
return -ENOENT;
}
if (index_to_find < cifsFile->srch_inf.index_of_last_entry) {
/* we found the buffer that contains the entry */
/* scan and find it */
int i;
char *current_entry;
char *end_of_smb = cifsFile->srch_inf.ntwrk_buf_start +
smbCalcSize((struct smb_hdr *)
cifsFile->srch_inf.ntwrk_buf_start);
current_entry = cifsFile->srch_inf.srch_entries_start;
first_entry_in_buffer = cifsFile->srch_inf.index_of_last_entry
- cifsFile->srch_inf.entries_in_buffer;
pos_in_buf = index_to_find - first_entry_in_buffer;
cFYI(1, ("found entry - pos_in_buf %d", pos_in_buf));
for (i = 0; (i < (pos_in_buf)) && (current_entry != NULL); i++) {
/* go entry by entry figuring out which is first */
current_entry = nxt_dir_entry(current_entry, end_of_smb,
cifsFile->srch_inf.info_level);
}
if ((current_entry == NULL) && (i < pos_in_buf)) {
/* BB fixme - check if we should flag this error */
cERROR(1, ("reached end of buf searching for pos in buf"
" %d index to find %lld rc %d",
pos_in_buf, index_to_find, rc));
}
rc = 0;
*ppCurrentEntry = current_entry;
} else {
cFYI(1, ("index not in buffer - could not findnext into it"));
return 0;
}
if (pos_in_buf >= cifsFile->srch_inf.entries_in_buffer) {
cFYI(1, ("can not return entries pos_in_buf beyond last"));
*num_to_ret = 0;
} else
*num_to_ret = cifsFile->srch_inf.entries_in_buffer - pos_in_buf;
return rc;
}
/* inode num, inode type and filename returned */
static int cifs_get_name_from_search_buf(struct qstr *pqst,
char *current_entry, __u16 level, unsigned int unicode,
struct cifs_sb_info *cifs_sb, int max_len, ino_t *pinum)
{
int rc = 0;
unsigned int len = 0;
char *filename;
struct nls_table *nlt = cifs_sb->local_nls;
*pinum = 0;
if (level == SMB_FIND_FILE_UNIX) {
FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
filename = &pFindData->FileName[0];
if (unicode) {
len = cifs_unicode_bytelen(filename);
} else {
/* BB should we make this strnlen of PATH_MAX? */
len = strnlen(filename, PATH_MAX);
}
/* BB fixme - hash low and high 32 bits if not 64 bit arch BB */
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)
*pinum = pFindData->UniqueId;
} else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
FILE_DIRECTORY_INFO *pFindData =
(FILE_DIRECTORY_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
} else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
FILE_FULL_DIRECTORY_INFO *pFindData =
(FILE_FULL_DIRECTORY_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
} else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
SEARCH_ID_FULL_DIR_INFO *pFindData =
(SEARCH_ID_FULL_DIR_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
*pinum = pFindData->UniqueId;
} else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
FILE_BOTH_DIRECTORY_INFO *pFindData =
(FILE_BOTH_DIRECTORY_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
} else if (level == SMB_FIND_FILE_INFO_STANDARD) {
FIND_FILE_STANDARD_INFO *pFindData =
(FIND_FILE_STANDARD_INFO *)current_entry;
filename = &pFindData->FileName[0];
/* one byte length, no name conversion */
len = (unsigned int)pFindData->FileNameLength;
} else {
cFYI(1, ("Unknown findfirst level %d", level));
return -EINVAL;
}
if (len > max_len) {
cERROR(1, ("bad search response length %d past smb end", len));
return -EINVAL;
}
if (unicode) {
/* BB fixme - test with long names */
/* Note converted filename can be longer than in unicode */
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MAP_SPECIAL_CHR)
pqst->len = cifs_convertUCSpath((char *)pqst->name,
(__le16 *)filename, len/2, nlt);
else
pqst->len = cifs_strfromUCS_le((char *)pqst->name,
(__le16 *)filename, len/2, nlt);
} else {
pqst->name = filename;
pqst->len = len;
}
pqst->hash = full_name_hash(pqst->name, pqst->len);
/* cFYI(1, ("filldir on %s",pqst->name)); */
return rc;
}
static int cifs_filldir(char *pfindEntry, struct file *file,
filldir_t filldir, void *direntry, char *scratch_buf, int max_len)
{
int rc = 0;
struct qstr qstring;
struct cifsFileInfo *pCifsF;
unsigned int obj_type;
ino_t inum;
struct cifs_sb_info *cifs_sb;
struct inode *tmp_inode;
struct dentry *tmp_dentry;
/* get filename and len into qstring */
/* get dentry */
/* decide whether to create and populate ionde */
if ((direntry == NULL) || (file == NULL))
return -EINVAL;
pCifsF = file->private_data;
if ((scratch_buf == NULL) || (pfindEntry == NULL) || (pCifsF == NULL))
return -ENOENT;
rc = cifs_entry_is_dot(pfindEntry, pCifsF);
/* skip . and .. since we added them first */
if (rc != 0)
return 0;
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
qstring.name = scratch_buf;
rc = cifs_get_name_from_search_buf(&qstring, pfindEntry,
pCifsF->srch_inf.info_level,
pCifsF->srch_inf.unicode, cifs_sb,
max_len,
&inum /* returned */);
if (rc)
return rc;
rc = construct_dentry(&qstring, file, &tmp_inode, &tmp_dentry);
if ((tmp_inode == NULL) || (tmp_dentry == NULL))
return -ENOMEM;
if (rc) {
/* inode created, we need to hash it with right inode number */
if (inum != 0) {
/* BB fixme - hash the 2 32 quantities bits together if
* necessary BB */
tmp_inode->i_ino = inum;
}
insert_inode_hash(tmp_inode);
}
/* we pass in rc below, indicating whether it is a new inode,
so we can figure out whether to invalidate the inode cached
data if the file has changed */
if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_UNIX)
unix_fill_in_inode(tmp_inode,
(FILE_UNIX_INFO *)pfindEntry,
&obj_type, rc);
else if (pCifsF->srch_inf.info_level == SMB_FIND_FILE_INFO_STANDARD)
fill_in_inode(tmp_inode, 0 /* old level 1 buffer type */,
pfindEntry, &obj_type, rc);
else
fill_in_inode(tmp_inode, 1 /* NT */, pfindEntry, &obj_type, rc);
if (rc) /* new inode - needs to be tied to dentry */ {
d_instantiate(tmp_dentry, tmp_inode);
if (rc == 2)
d_rehash(tmp_dentry);
}
rc = filldir(direntry, qstring.name, qstring.len, file->f_pos,
tmp_inode->i_ino, obj_type);
if (rc) {
cFYI(1, ("filldir rc = %d", rc));
/* we can not return filldir errors to the caller
since they are "normal" when the stat blocksize
is too small - we return remapped error instead */
rc = -EOVERFLOW;
}
dput(tmp_dentry);
return rc;
}
static int cifs_save_resume_key(const char *current_entry,
struct cifsFileInfo *cifsFile)
{
int rc = 0;
unsigned int len = 0;
__u16 level;
char *filename;
if ((cifsFile == NULL) || (current_entry == NULL))
return -EINVAL;
level = cifsFile->srch_inf.info_level;
if (level == SMB_FIND_FILE_UNIX) {
FILE_UNIX_INFO *pFindData = (FILE_UNIX_INFO *)current_entry;
filename = &pFindData->FileName[0];
if (cifsFile->srch_inf.unicode) {
len = cifs_unicode_bytelen(filename);
} else {
/* BB should we make this strnlen of PATH_MAX? */
len = strnlen(filename, PATH_MAX);
}
cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
} else if (level == SMB_FIND_FILE_DIRECTORY_INFO) {
FILE_DIRECTORY_INFO *pFindData =
(FILE_DIRECTORY_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
cifsFile->srch_inf.resume_key = pFindData->FileIndex;
} else if (level == SMB_FIND_FILE_FULL_DIRECTORY_INFO) {
FILE_FULL_DIRECTORY_INFO *pFindData =
(FILE_FULL_DIRECTORY_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
cifsFile->srch_inf.resume_key = pFindData->FileIndex;
} else if (level == SMB_FIND_FILE_ID_FULL_DIR_INFO) {
SEARCH_ID_FULL_DIR_INFO *pFindData =
(SEARCH_ID_FULL_DIR_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
cifsFile->srch_inf.resume_key = pFindData->FileIndex;
} else if (level == SMB_FIND_FILE_BOTH_DIRECTORY_INFO) {
FILE_BOTH_DIRECTORY_INFO *pFindData =
(FILE_BOTH_DIRECTORY_INFO *)current_entry;
filename = &pFindData->FileName[0];
len = le32_to_cpu(pFindData->FileNameLength);
cifsFile->srch_inf.resume_key = pFindData->FileIndex;
} else if (level == SMB_FIND_FILE_INFO_STANDARD) {
FIND_FILE_STANDARD_INFO *pFindData =
(FIND_FILE_STANDARD_INFO *)current_entry;
filename = &pFindData->FileName[0];
/* one byte length, no name conversion */
len = (unsigned int)pFindData->FileNameLength;
cifsFile->srch_inf.resume_key = pFindData->ResumeKey;
} else {
cFYI(1, ("Unknown findfirst level %d", level));
return -EINVAL;
}
cifsFile->srch_inf.resume_name_len = len;
cifsFile->srch_inf.presume_name = filename;
return rc;
}
int cifs_readdir(struct file *file, void *direntry, filldir_t filldir)
{
int rc = 0;
int xid, i;
struct cifs_sb_info *cifs_sb;
struct cifsTconInfo *pTcon;
struct cifsFileInfo *cifsFile = NULL;
char *current_entry;
int num_to_fill = 0;
char *tmp_buf = NULL;
char *end_of_smb;
int max_len;
xid = GetXid();
cifs_sb = CIFS_SB(file->f_path.dentry->d_sb);
pTcon = cifs_sb->tcon;
if (pTcon == NULL)
return -EINVAL;
switch ((int) file->f_pos) {
case 0:
if (filldir(direntry, ".", 1, file->f_pos,
file->f_path.dentry->d_inode->i_ino, DT_DIR) < 0) {
cERROR(1, ("Filldir for current dir failed"));
rc = -ENOMEM;
break;
}
file->f_pos++;
case 1:
if (filldir(direntry, "..", 2, file->f_pos,
file->f_path.dentry->d_parent->d_inode->i_ino, DT_DIR) < 0) {
cERROR(1, ("Filldir for parent dir failed"));
rc = -ENOMEM;
break;
}
file->f_pos++;
default:
/* 1) If search is active,
is in current search buffer?
if it before then restart search
if after then keep searching till find it */
if (file->private_data == NULL) {
rc = initiate_cifs_search(xid, file);
cFYI(1, ("initiate cifs search rc %d", rc));
if (rc) {
FreeXid(xid);
return rc;
}
}
if (file->private_data == NULL) {
rc = -EINVAL;
FreeXid(xid);
return rc;
}
cifsFile = file->private_data;
if (cifsFile->srch_inf.endOfSearch) {
if (cifsFile->srch_inf.emptyDir) {
cFYI(1, ("End of search, empty dir"));
rc = 0;
break;
}
} /* else {
cifsFile->invalidHandle = true;
CIFSFindClose(xid, pTcon, cifsFile->netfid);
} */
rc = find_cifs_entry(xid, pTcon, file,
&current_entry, &num_to_fill);
if (rc) {
cFYI(1, ("fce error %d", rc));
goto rddir2_exit;
} else if (current_entry != NULL) {
cFYI(1, ("entry %lld found", file->f_pos));
} else {
cFYI(1, ("could not find entry"));
goto rddir2_exit;
}
cFYI(1, ("loop through %d times filling dir for net buf %p",
num_to_fill, cifsFile->srch_inf.ntwrk_buf_start));
max_len = smbCalcSize((struct smb_hdr *)
cifsFile->srch_inf.ntwrk_buf_start);
end_of_smb = cifsFile->srch_inf.ntwrk_buf_start + max_len;
/* To be safe - for UCS to UTF-8 with strings loaded
with the rare long characters alloc more to account for
such multibyte target UTF-8 characters. cifs_unicode.c,
which actually does the conversion, has the same limit */
tmp_buf = kmalloc((2 * NAME_MAX) + 4, GFP_KERNEL);
for (i = 0; (i < num_to_fill) && (rc == 0); i++) {
if (current_entry == NULL) {
/* evaluate whether this case is an error */
cERROR(1, ("past SMB end, num to fill %d i %d",
num_to_fill, i));
break;
}
/* if buggy server returns . and .. late do
we want to check for that here? */
rc = cifs_filldir(current_entry, file,
filldir, direntry, tmp_buf, max_len);
if (rc == -EOVERFLOW) {
rc = 0;
break;
}
file->f_pos++;
if (file->f_pos ==
cifsFile->srch_inf.index_of_last_entry) {
cFYI(1, ("last entry in buf at pos %lld %s",
file->f_pos, tmp_buf));
cifs_save_resume_key(current_entry, cifsFile);
break;
} else
current_entry =
nxt_dir_entry(current_entry, end_of_smb,
cifsFile->srch_inf.info_level);
}
kfree(tmp_buf);
break;
} /* end switch */
rddir2_exit:
FreeXid(xid);
return rc;
}
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