linux/fs/cifs/link.c

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// SPDX-License-Identifier: LGPL-2.1
/*
*
* Copyright (C) International Business Machines Corp., 2002,2008
* Author(s): Steve French (sfrench@us.ibm.com)
*
*/
#include <linux/fs.h>
#include <linux/stat.h>
include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-24 16:04:11 +08:00
#include <linux/slab.h>
#include <linux/namei.h>
#include "cifsfs.h"
#include "cifspdu.h"
#include "cifsglob.h"
#include "cifsproto.h"
#include "cifs_debug.h"
#include "cifs_fs_sb.h"
Remap reserved posix characters by default (part 3/3) This is a bigger patch, but its size is mostly due to a single change for how we check for remapping illegal characters in file names - a lot of repeated, small changes to the way callers request converting file names. The final patch in the series does the following: 1) changes default behavior for cifs to be more intuitive. Currently we do not map by default to seven reserved characters, ie those valid in POSIX but not in NTFS/CIFS/SMB3/Windows, unless a mount option (mapchars) is specified. Change this to by default always map and map using the SFM maping (like the Mac uses) unless the server negotiates the CIFS Unix Extensions (like Samba does when mounting with the cifs protocol) when the remapping of the characters is unnecessary. This should help SMB3 mounts in particular since Samba will likely be able to implement this mapping with its new "vfs_fruit" module as it will be doing for the Mac. 2) if the user specifies the existing "mapchars" mount option then use the "SFU" (Microsoft Services for Unix, SUA) style mapping of the seven characters instead. 3) if the user specifies "nomapposix" then disable SFM/MAC style mapping (so no character remapping would be used unless the user specifies "mapchars" on mount as well, as above). 4) change all the places in the code that check for the superblock flag on the mount which is set by mapchars and passed in on all path based operation and change it to use a small function call instead to set the mapping type properly (and check for the mapping type in the cifs unicode functions) Signed-off-by: Steve French <smfrench@gmail.com>
2014-09-27 15:19:01 +08:00
#include "cifs_unicode.h"
#include "smb2proto.h"
#include "cifs_ioctl.h"
/*
* M-F Symlink Functions - Begin
*/
#define CIFS_MF_SYMLINK_LEN_OFFSET (4+1)
#define CIFS_MF_SYMLINK_MD5_OFFSET (CIFS_MF_SYMLINK_LEN_OFFSET+(4+1))
#define CIFS_MF_SYMLINK_LINK_OFFSET (CIFS_MF_SYMLINK_MD5_OFFSET+(32+1))
#define CIFS_MF_SYMLINK_LINK_MAXLEN (1024)
#define CIFS_MF_SYMLINK_FILE_SIZE \
(CIFS_MF_SYMLINK_LINK_OFFSET + CIFS_MF_SYMLINK_LINK_MAXLEN)
#define CIFS_MF_SYMLINK_LEN_FORMAT "XSym\n%04u\n"
#define CIFS_MF_SYMLINK_MD5_FORMAT "%16phN\n"
#define CIFS_MF_SYMLINK_MD5_ARGS(md5_hash) md5_hash
static int
symlink_hash(unsigned int link_len, const char *link_str, u8 *md5_hash)
{
int rc;
struct crypto_shash *md5 = NULL;
struct sdesc *sdescmd5 = NULL;
rc = cifs_alloc_hash("md5", &md5, &sdescmd5);
if (rc)
goto symlink_hash_err;
rc = crypto_shash_init(&sdescmd5->shash);
if (rc) {
cifs_dbg(VFS, "%s: Could not init md5 shash\n", __func__);
goto symlink_hash_err;
}
rc = crypto_shash_update(&sdescmd5->shash, link_str, link_len);
if (rc) {
cifs_dbg(VFS, "%s: Could not update with link_str\n", __func__);
goto symlink_hash_err;
}
rc = crypto_shash_final(&sdescmd5->shash, md5_hash);
if (rc)
cifs_dbg(VFS, "%s: Could not generate md5 hash\n", __func__);
symlink_hash_err:
cifs_free_hash(&md5, &sdescmd5);
return rc;
}
static int
parse_mf_symlink(const u8 *buf, unsigned int buf_len, unsigned int *_link_len,
char **_link_str)
{
int rc;
unsigned int link_len;
const char *md5_str1;
const char *link_str;
u8 md5_hash[16];
char md5_str2[34];
if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
return -EINVAL;
md5_str1 = (const char *)&buf[CIFS_MF_SYMLINK_MD5_OFFSET];
link_str = (const char *)&buf[CIFS_MF_SYMLINK_LINK_OFFSET];
rc = sscanf(buf, CIFS_MF_SYMLINK_LEN_FORMAT, &link_len);
if (rc != 1)
return -EINVAL;
if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
return -EINVAL;
rc = symlink_hash(link_len, link_str, md5_hash);
if (rc) {
cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
return rc;
}
scnprintf(md5_str2, sizeof(md5_str2),
CIFS_MF_SYMLINK_MD5_FORMAT,
CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
if (strncmp(md5_str1, md5_str2, 17) != 0)
return -EINVAL;
if (_link_str) {
*_link_str = kstrndup(link_str, link_len, GFP_KERNEL);
if (!*_link_str)
return -ENOMEM;
}
*_link_len = link_len;
return 0;
}
static int
format_mf_symlink(u8 *buf, unsigned int buf_len, const char *link_str)
{
int rc;
unsigned int link_len;
unsigned int ofs;
u8 md5_hash[16];
if (buf_len != CIFS_MF_SYMLINK_FILE_SIZE)
return -EINVAL;
link_len = strlen(link_str);
if (link_len > CIFS_MF_SYMLINK_LINK_MAXLEN)
return -ENAMETOOLONG;
rc = symlink_hash(link_len, link_str, md5_hash);
if (rc) {
cifs_dbg(FYI, "%s: MD5 hash failure: %d\n", __func__, rc);
return rc;
}
scnprintf(buf, buf_len,
CIFS_MF_SYMLINK_LEN_FORMAT CIFS_MF_SYMLINK_MD5_FORMAT,
link_len,
CIFS_MF_SYMLINK_MD5_ARGS(md5_hash));
ofs = CIFS_MF_SYMLINK_LINK_OFFSET;
memcpy(buf + ofs, link_str, link_len);
ofs += link_len;
if (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
buf[ofs] = '\n';
ofs++;
}
while (ofs < CIFS_MF_SYMLINK_FILE_SIZE) {
buf[ofs] = ' ';
ofs++;
}
return 0;
}
bool
couldbe_mf_symlink(const struct cifs_fattr *fattr)
{
if (!S_ISREG(fattr->cf_mode))
/* it's not a symlink */
return false;
if (fattr->cf_eof != CIFS_MF_SYMLINK_FILE_SIZE)
/* it's not a symlink */
return false;
return true;
}
static int
create_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, const char *fromName,
const char *toName)
{
int rc;
u8 *buf;
unsigned int bytes_written = 0;
buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
if (!buf)
return -ENOMEM;
rc = format_mf_symlink(buf, CIFS_MF_SYMLINK_FILE_SIZE, toName);
if (rc)
goto out;
if (tcon->ses->server->ops->create_mf_symlink)
rc = tcon->ses->server->ops->create_mf_symlink(xid, tcon,
cifs_sb, fromName, buf, &bytes_written);
else
rc = -EOPNOTSUPP;
if (rc)
goto out;
if (bytes_written != CIFS_MF_SYMLINK_FILE_SIZE)
rc = -EIO;
out:
kfree(buf);
return rc;
}
static int
query_mf_symlink(const unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, const unsigned char *path,
char **symlinkinfo)
{
int rc;
u8 *buf = NULL;
unsigned int link_len = 0;
unsigned int bytes_read = 0;
buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
if (!buf)
return -ENOMEM;
if (tcon->ses->server->ops->query_mf_symlink)
rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon,
cifs_sb, path, buf, &bytes_read);
else
rc = -ENOSYS;
if (rc)
goto out;
if (bytes_read == 0) { /* not a symlink */
rc = -EINVAL;
goto out;
}
rc = parse_mf_symlink(buf, bytes_read, &link_len, symlinkinfo);
out:
kfree(buf);
return rc;
}
int
check_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, struct cifs_fattr *fattr,
const unsigned char *path)
{
int rc;
u8 *buf = NULL;
unsigned int link_len = 0;
unsigned int bytes_read = 0;
if (!couldbe_mf_symlink(fattr))
/* it's not a symlink */
return 0;
buf = kmalloc(CIFS_MF_SYMLINK_FILE_SIZE, GFP_KERNEL);
if (!buf)
return -ENOMEM;
if (tcon->ses->server->ops->query_mf_symlink)
rc = tcon->ses->server->ops->query_mf_symlink(xid, tcon,
cifs_sb, path, buf, &bytes_read);
else
rc = -ENOSYS;
if (rc)
goto out;
if (bytes_read == 0) /* not a symlink */
goto out;
rc = parse_mf_symlink(buf, bytes_read, &link_len, NULL);
if (rc == -EINVAL) {
/* it's not a symlink */
rc = 0;
goto out;
}
if (rc != 0)
goto out;
/* it is a symlink */
fattr->cf_eof = link_len;
fattr->cf_mode &= ~S_IFMT;
fattr->cf_mode |= S_IFLNK | S_IRWXU | S_IRWXG | S_IRWXO;
fattr->cf_dtype = DT_LNK;
out:
kfree(buf);
return rc;
}
#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
/*
* SMB 1.0 Protocol specific functions
*/
int
cifs_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, const unsigned char *path,
char *pbuf, unsigned int *pbytes_read)
{
int rc;
int oplock = 0;
struct cifs_fid fid;
struct cifs_open_parms oparms;
struct cifs_io_parms io_parms = {0};
int buf_type = CIFS_NO_BUFFER;
FILE_ALL_INFO file_info;
oparms.tcon = tcon;
oparms.cifs_sb = cifs_sb;
oparms.desired_access = GENERIC_READ;
oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
oparms.disposition = FILE_OPEN;
oparms.path = path;
oparms.fid = &fid;
oparms.reconnect = false;
rc = CIFS_open(xid, &oparms, &oplock, &file_info);
if (rc)
return rc;
if (file_info.EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
rc = -ENOENT;
/* it's not a symlink */
goto out;
}
io_parms.netfid = fid.netfid;
io_parms.pid = current->tgid;
io_parms.tcon = tcon;
io_parms.offset = 0;
io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
rc = CIFSSMBRead(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
out:
CIFSSMBClose(xid, tcon, fid.netfid);
return rc;
}
int
cifs_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, const unsigned char *path,
char *pbuf, unsigned int *pbytes_written)
{
int rc;
int oplock = 0;
struct cifs_fid fid;
struct cifs_open_parms oparms;
struct cifs_io_parms io_parms = {0};
oparms.tcon = tcon;
oparms.cifs_sb = cifs_sb;
oparms.desired_access = GENERIC_WRITE;
oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
oparms.disposition = FILE_CREATE;
oparms.path = path;
oparms.fid = &fid;
oparms.reconnect = false;
rc = CIFS_open(xid, &oparms, &oplock, NULL);
if (rc)
return rc;
io_parms.netfid = fid.netfid;
io_parms.pid = current->tgid;
io_parms.tcon = tcon;
io_parms.offset = 0;
io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
rc = CIFSSMBWrite(xid, &io_parms, pbytes_written, pbuf);
CIFSSMBClose(xid, tcon, fid.netfid);
return rc;
}
#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
/*
* SMB 2.1/SMB3 Protocol specific functions
*/
int
smb3_query_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, const unsigned char *path,
char *pbuf, unsigned int *pbytes_read)
{
int rc;
struct cifs_fid fid;
struct cifs_open_parms oparms;
struct cifs_io_parms io_parms = {0};
int buf_type = CIFS_NO_BUFFER;
__le16 *utf16_path;
__u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
struct smb2_file_all_info *pfile_info = NULL;
oparms.tcon = tcon;
oparms.cifs_sb = cifs_sb;
oparms.desired_access = GENERIC_READ;
oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
oparms.disposition = FILE_OPEN;
oparms.fid = &fid;
oparms.reconnect = false;
utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
if (utf16_path == NULL)
return -ENOMEM;
pfile_info = kzalloc(sizeof(struct smb2_file_all_info) + PATH_MAX * 2,
GFP_KERNEL);
if (pfile_info == NULL) {
kfree(utf16_path);
return -ENOMEM;
}
rc = SMB2_open(xid, &oparms, utf16_path, &oplock, pfile_info, NULL,
NULL, NULL);
if (rc)
goto qmf_out_open_fail;
if (pfile_info->EndOfFile != cpu_to_le64(CIFS_MF_SYMLINK_FILE_SIZE)) {
/* it's not a symlink */
rc = -ENOENT; /* Is there a better rc to return? */
goto qmf_out;
}
io_parms.netfid = fid.netfid;
io_parms.pid = current->tgid;
io_parms.tcon = tcon;
io_parms.offset = 0;
io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
io_parms.persistent_fid = fid.persistent_fid;
io_parms.volatile_fid = fid.volatile_fid;
rc = SMB2_read(xid, &io_parms, pbytes_read, &pbuf, &buf_type);
qmf_out:
SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
qmf_out_open_fail:
kfree(utf16_path);
kfree(pfile_info);
return rc;
}
int
smb3_create_mf_symlink(unsigned int xid, struct cifs_tcon *tcon,
struct cifs_sb_info *cifs_sb, const unsigned char *path,
char *pbuf, unsigned int *pbytes_written)
{
int rc;
struct cifs_fid fid;
struct cifs_open_parms oparms;
cifs: multichannel: move channel selection above transport layer Move the channel (TCP_Server_Info*) selection from the tranport layer to higher in the call stack so that: - credit handling is done with the server that will actually be used to send. * ->wait_mtu_credit * ->set_credits / set_credits * ->add_credits / add_credits * add_credits_and_wake_if - potential reconnection (smb2_reconnect) done when initializing a request is checked and done with the server that will actually be used to send. To do this: - remove the cifs_pick_channel() call out of compound_send_recv() - select channel and pass it down by adding a cifs_pick_channel(ses) call in: - smb311_posix_mkdir - SMB2_open - SMB2_ioctl - __SMB2_close - query_info - SMB2_change_notify - SMB2_flush - smb2_async_readv (if none provided in context param) - SMB2_read (if none provided in context param) - smb2_async_writev (if none provided in context param) - SMB2_write (if none provided in context param) - SMB2_query_directory - send_set_info - SMB2_oplock_break - SMB311_posix_qfs_info - SMB2_QFS_info - SMB2_QFS_attr - smb2_lockv - SMB2_lease_break - smb2_compound_op - smb2_set_ea - smb2_ioctl_query_info - smb2_query_dir_first - smb2_query_info_comound - smb2_query_symlink - cifs_writepages - cifs_write_from_iter - cifs_send_async_read - cifs_read - cifs_readpages - add TCP_Server_Info *server param argument to: - cifs_send_recv - compound_send_recv - SMB2_open_init - SMB2_query_info_init - SMB2_set_info_init - SMB2_close_init - SMB2_ioctl_init - smb2_iotcl_req_init - SMB2_query_directory_init - SMB2_notify_init - SMB2_flush_init - build_qfs_info_req - smb2_hdr_assemble - smb2_reconnect - fill_small_buf - smb2_plain_req_init - __smb2_plain_req_init The read/write codepath is different than the rest as it is using pages, io iterators and async calls. To deal with those we add a server pointer in the cifs_writedata/cifs_readdata/cifs_io_parms context struct and set it in: - cifs_writepages (wdata) - cifs_write_from_iter (wdata) - cifs_readpages (rdata) - cifs_send_async_read (rdata) The [rw]data->server pointer is eventually copied to cifs_io_parms->server to pass it down to SMB2_read/SMB2_write. If SMB2_read/SMB2_write is called from a different place that doesn't set the server field it will pick a channel. Some places do not pick a channel and just use ses->server or cifs_ses_server(ses). All cifs_ses_server(ses) calls are in codepaths involving negprot/sess.setup. - SMB2_negotiate (binding channel) - SMB2_sess_alloc_buffer (binding channel) - SMB2_echo (uses provided one) - SMB2_logoff (uses master) - SMB2_tdis (uses master) (list not exhaustive) Signed-off-by: Aurelien Aptel <aaptel@suse.com> Signed-off-by: Steve French <stfrench@microsoft.com>
2020-06-01 01:38:22 +08:00
struct cifs_io_parms io_parms = {0};
__le16 *utf16_path;
__u8 oplock = SMB2_OPLOCK_LEVEL_NONE;
struct kvec iov[2];
cifs_dbg(FYI, "%s: path: %s\n", __func__, path);
utf16_path = cifs_convert_path_to_utf16(path, cifs_sb);
if (!utf16_path)
return -ENOMEM;
oparms.tcon = tcon;
oparms.cifs_sb = cifs_sb;
oparms.desired_access = GENERIC_WRITE;
oparms.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR);
oparms.disposition = FILE_CREATE;
oparms.fid = &fid;
oparms.reconnect = false;
rc = SMB2_open(xid, &oparms, utf16_path, &oplock, NULL, NULL,
NULL, NULL);
if (rc) {
kfree(utf16_path);
return rc;
}
io_parms.netfid = fid.netfid;
io_parms.pid = current->tgid;
io_parms.tcon = tcon;
io_parms.offset = 0;
io_parms.length = CIFS_MF_SYMLINK_FILE_SIZE;
io_parms.persistent_fid = fid.persistent_fid;
io_parms.volatile_fid = fid.volatile_fid;
/* iov[0] is reserved for smb header */
iov[1].iov_base = pbuf;
iov[1].iov_len = CIFS_MF_SYMLINK_FILE_SIZE;
rc = SMB2_write(xid, &io_parms, pbytes_written, iov, 1);
/* Make sure we wrote all of the symlink data */
if ((rc == 0) && (*pbytes_written != CIFS_MF_SYMLINK_FILE_SIZE))
rc = -EIO;
SMB2_close(xid, tcon, fid.persistent_fid, fid.volatile_fid);
kfree(utf16_path);
return rc;
}
/*
* M-F Symlink Functions - End
*/
int
cifs_hardlink(struct dentry *old_file, struct inode *inode,
struct dentry *direntry)
{
int rc = -EACCES;
unsigned int xid;
cifs: allocate buffer in the caller of build_path_from_dentry() build_path_from_dentry() open-codes dentry_path_raw(). The reason we can't use dentry_path_raw() in there (and postprocess the result as needed) is that the callers of build_path_from_dentry() expect that the object to be freed on cleanup and the string to be used are at the same address. That's painful, since the path is naturally built end-to-beginning - we start at the leaf and go through the ancestors, accumulating the pathname. Life would be easier if we left the buffer allocation to callers. It wouldn't be exact-sized buffer, but none of the callers keep the result for long - it's always freed before the caller returns. So there's no need to do exact-sized allocation; better use __getname()/__putname(), same as we do for pathname arguments of syscalls. What's more, there's no need to do allocation under spinlocks, so GFP_ATOMIC is not needed. Next patch will replace the open-coded dentry_path_raw() (in build_path_from_dentry_optional_prefix()) with calling the real thing. This patch only introduces wrappers for allocating/freeing the buffers and switches to new calling conventions: build_path_from_dentry(dentry, buf) expects buf to be address of a page-sized object or NULL, return value is a pathname built inside that buffer on success, ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if the pathname won't fit into page. Note that we don't need to check for failure when allocating the buffer in the caller - build_path_from_dentry() will do the right thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 06:36:04 +08:00
const char *from_name, *to_name;
void *page1, *page2;
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
struct tcon_link *tlink;
struct cifs_tcon *tcon;
struct TCP_Server_Info *server;
struct cifsInodeInfo *cifsInode;
if (unlikely(cifs_forced_shutdown(cifs_sb)))
return -EIO;
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink))
return PTR_ERR(tlink);
tcon = tlink_tcon(tlink);
xid = get_xid();
cifs: allocate buffer in the caller of build_path_from_dentry() build_path_from_dentry() open-codes dentry_path_raw(). The reason we can't use dentry_path_raw() in there (and postprocess the result as needed) is that the callers of build_path_from_dentry() expect that the object to be freed on cleanup and the string to be used are at the same address. That's painful, since the path is naturally built end-to-beginning - we start at the leaf and go through the ancestors, accumulating the pathname. Life would be easier if we left the buffer allocation to callers. It wouldn't be exact-sized buffer, but none of the callers keep the result for long - it's always freed before the caller returns. So there's no need to do exact-sized allocation; better use __getname()/__putname(), same as we do for pathname arguments of syscalls. What's more, there's no need to do allocation under spinlocks, so GFP_ATOMIC is not needed. Next patch will replace the open-coded dentry_path_raw() (in build_path_from_dentry_optional_prefix()) with calling the real thing. This patch only introduces wrappers for allocating/freeing the buffers and switches to new calling conventions: build_path_from_dentry(dentry, buf) expects buf to be address of a page-sized object or NULL, return value is a pathname built inside that buffer on success, ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if the pathname won't fit into page. Note that we don't need to check for failure when allocating the buffer in the caller - build_path_from_dentry() will do the right thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 06:36:04 +08:00
page1 = alloc_dentry_path();
page2 = alloc_dentry_path();
cifs: allocate buffer in the caller of build_path_from_dentry() build_path_from_dentry() open-codes dentry_path_raw(). The reason we can't use dentry_path_raw() in there (and postprocess the result as needed) is that the callers of build_path_from_dentry() expect that the object to be freed on cleanup and the string to be used are at the same address. That's painful, since the path is naturally built end-to-beginning - we start at the leaf and go through the ancestors, accumulating the pathname. Life would be easier if we left the buffer allocation to callers. It wouldn't be exact-sized buffer, but none of the callers keep the result for long - it's always freed before the caller returns. So there's no need to do exact-sized allocation; better use __getname()/__putname(), same as we do for pathname arguments of syscalls. What's more, there's no need to do allocation under spinlocks, so GFP_ATOMIC is not needed. Next patch will replace the open-coded dentry_path_raw() (in build_path_from_dentry_optional_prefix()) with calling the real thing. This patch only introduces wrappers for allocating/freeing the buffers and switches to new calling conventions: build_path_from_dentry(dentry, buf) expects buf to be address of a page-sized object or NULL, return value is a pathname built inside that buffer on success, ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if the pathname won't fit into page. Note that we don't need to check for failure when allocating the buffer in the caller - build_path_from_dentry() will do the right thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 06:36:04 +08:00
from_name = build_path_from_dentry(old_file, page1);
if (IS_ERR(from_name)) {
rc = PTR_ERR(from_name);
goto cifs_hl_exit;
}
to_name = build_path_from_dentry(direntry, page2);
if (IS_ERR(to_name)) {
rc = PTR_ERR(to_name);
goto cifs_hl_exit;
}
#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
if (tcon->unix_ext)
rc = CIFSUnixCreateHardLink(xid, tcon, from_name, to_name,
cifs_sb->local_nls,
Remap reserved posix characters by default (part 3/3) This is a bigger patch, but its size is mostly due to a single change for how we check for remapping illegal characters in file names - a lot of repeated, small changes to the way callers request converting file names. The final patch in the series does the following: 1) changes default behavior for cifs to be more intuitive. Currently we do not map by default to seven reserved characters, ie those valid in POSIX but not in NTFS/CIFS/SMB3/Windows, unless a mount option (mapchars) is specified. Change this to by default always map and map using the SFM maping (like the Mac uses) unless the server negotiates the CIFS Unix Extensions (like Samba does when mounting with the cifs protocol) when the remapping of the characters is unnecessary. This should help SMB3 mounts in particular since Samba will likely be able to implement this mapping with its new "vfs_fruit" module as it will be doing for the Mac. 2) if the user specifies the existing "mapchars" mount option then use the "SFU" (Microsoft Services for Unix, SUA) style mapping of the seven characters instead. 3) if the user specifies "nomapposix" then disable SFM/MAC style mapping (so no character remapping would be used unless the user specifies "mapchars" on mount as well, as above). 4) change all the places in the code that check for the superblock flag on the mount which is set by mapchars and passed in on all path based operation and change it to use a small function call instead to set the mapping type properly (and check for the mapping type in the cifs unicode functions) Signed-off-by: Steve French <smfrench@gmail.com>
2014-09-27 15:19:01 +08:00
cifs_remap(cifs_sb));
else {
#else
{
#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
server = tcon->ses->server;
if (!server->ops->create_hardlink) {
rc = -ENOSYS;
goto cifs_hl_exit;
}
rc = server->ops->create_hardlink(xid, tcon, from_name, to_name,
cifs_sb);
if ((rc == -EIO) || (rc == -EINVAL))
rc = -EOPNOTSUPP;
}
d_drop(direntry); /* force new lookup from server of target */
/*
* if source file is cached (oplocked) revalidate will not go to server
* until the file is closed or oplock broken so update nlinks locally
*/
if (d_really_is_positive(old_file)) {
cifsInode = CIFS_I(d_inode(old_file));
if (rc == 0) {
spin_lock(&d_inode(old_file)->i_lock);
inc_nlink(d_inode(old_file));
spin_unlock(&d_inode(old_file)->i_lock);
/*
* parent dir timestamps will update from srv within a
* second, would it really be worth it to set the parent
* dir cifs inode time to zero to force revalidate
* (faster) for it too?
*/
}
/*
* if not oplocked will force revalidate to get info on source
* file from srv. Note Samba server prior to 4.2 has bug -
* not updating src file ctime on hardlinks but Windows servers
* handle it properly
*/
cifsInode->time = 0;
/*
* Will update parent dir timestamps from srv within a second.
* Would it really be worth it to set the parent dir (cifs
* inode) time field to zero to force revalidate on parent
* directory faster ie
*
* CIFS_I(inode)->time = 0;
*/
}
cifs_hl_exit:
cifs: allocate buffer in the caller of build_path_from_dentry() build_path_from_dentry() open-codes dentry_path_raw(). The reason we can't use dentry_path_raw() in there (and postprocess the result as needed) is that the callers of build_path_from_dentry() expect that the object to be freed on cleanup and the string to be used are at the same address. That's painful, since the path is naturally built end-to-beginning - we start at the leaf and go through the ancestors, accumulating the pathname. Life would be easier if we left the buffer allocation to callers. It wouldn't be exact-sized buffer, but none of the callers keep the result for long - it's always freed before the caller returns. So there's no need to do exact-sized allocation; better use __getname()/__putname(), same as we do for pathname arguments of syscalls. What's more, there's no need to do allocation under spinlocks, so GFP_ATOMIC is not needed. Next patch will replace the open-coded dentry_path_raw() (in build_path_from_dentry_optional_prefix()) with calling the real thing. This patch only introduces wrappers for allocating/freeing the buffers and switches to new calling conventions: build_path_from_dentry(dentry, buf) expects buf to be address of a page-sized object or NULL, return value is a pathname built inside that buffer on success, ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if the pathname won't fit into page. Note that we don't need to check for failure when allocating the buffer in the caller - build_path_from_dentry() will do the right thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 06:36:04 +08:00
free_dentry_path(page1);
free_dentry_path(page2);
free_xid(xid);
cifs_put_tlink(tlink);
return rc;
}
const char *
cifs_get_link(struct dentry *direntry, struct inode *inode,
struct delayed_call *done)
{
int rc = -ENOMEM;
unsigned int xid;
cifs: allocate buffer in the caller of build_path_from_dentry() build_path_from_dentry() open-codes dentry_path_raw(). The reason we can't use dentry_path_raw() in there (and postprocess the result as needed) is that the callers of build_path_from_dentry() expect that the object to be freed on cleanup and the string to be used are at the same address. That's painful, since the path is naturally built end-to-beginning - we start at the leaf and go through the ancestors, accumulating the pathname. Life would be easier if we left the buffer allocation to callers. It wouldn't be exact-sized buffer, but none of the callers keep the result for long - it's always freed before the caller returns. So there's no need to do exact-sized allocation; better use __getname()/__putname(), same as we do for pathname arguments of syscalls. What's more, there's no need to do allocation under spinlocks, so GFP_ATOMIC is not needed. Next patch will replace the open-coded dentry_path_raw() (in build_path_from_dentry_optional_prefix()) with calling the real thing. This patch only introduces wrappers for allocating/freeing the buffers and switches to new calling conventions: build_path_from_dentry(dentry, buf) expects buf to be address of a page-sized object or NULL, return value is a pathname built inside that buffer on success, ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if the pathname won't fit into page. Note that we don't need to check for failure when allocating the buffer in the caller - build_path_from_dentry() will do the right thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 06:36:04 +08:00
const char *full_path;
void *page;
char *target_path = NULL;
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
struct tcon_link *tlink = NULL;
struct cifs_tcon *tcon;
struct TCP_Server_Info *server;
if (!direntry)
return ERR_PTR(-ECHILD);
xid = get_xid();
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink)) {
free_xid(xid);
return ERR_CAST(tlink);
}
tcon = tlink_tcon(tlink);
server = tcon->ses->server;
cifs: allocate buffer in the caller of build_path_from_dentry() build_path_from_dentry() open-codes dentry_path_raw(). The reason we can't use dentry_path_raw() in there (and postprocess the result as needed) is that the callers of build_path_from_dentry() expect that the object to be freed on cleanup and the string to be used are at the same address. That's painful, since the path is naturally built end-to-beginning - we start at the leaf and go through the ancestors, accumulating the pathname. Life would be easier if we left the buffer allocation to callers. It wouldn't be exact-sized buffer, but none of the callers keep the result for long - it's always freed before the caller returns. So there's no need to do exact-sized allocation; better use __getname()/__putname(), same as we do for pathname arguments of syscalls. What's more, there's no need to do allocation under spinlocks, so GFP_ATOMIC is not needed. Next patch will replace the open-coded dentry_path_raw() (in build_path_from_dentry_optional_prefix()) with calling the real thing. This patch only introduces wrappers for allocating/freeing the buffers and switches to new calling conventions: build_path_from_dentry(dentry, buf) expects buf to be address of a page-sized object or NULL, return value is a pathname built inside that buffer on success, ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if the pathname won't fit into page. Note that we don't need to check for failure when allocating the buffer in the caller - build_path_from_dentry() will do the right thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 06:36:04 +08:00
page = alloc_dentry_path();
full_path = build_path_from_dentry(direntry, page);
if (IS_ERR(full_path)) {
free_xid(xid);
cifs_put_tlink(tlink);
cifs: allocate buffer in the caller of build_path_from_dentry() build_path_from_dentry() open-codes dentry_path_raw(). The reason we can't use dentry_path_raw() in there (and postprocess the result as needed) is that the callers of build_path_from_dentry() expect that the object to be freed on cleanup and the string to be used are at the same address. That's painful, since the path is naturally built end-to-beginning - we start at the leaf and go through the ancestors, accumulating the pathname. Life would be easier if we left the buffer allocation to callers. It wouldn't be exact-sized buffer, but none of the callers keep the result for long - it's always freed before the caller returns. So there's no need to do exact-sized allocation; better use __getname()/__putname(), same as we do for pathname arguments of syscalls. What's more, there's no need to do allocation under spinlocks, so GFP_ATOMIC is not needed. Next patch will replace the open-coded dentry_path_raw() (in build_path_from_dentry_optional_prefix()) with calling the real thing. This patch only introduces wrappers for allocating/freeing the buffers and switches to new calling conventions: build_path_from_dentry(dentry, buf) expects buf to be address of a page-sized object or NULL, return value is a pathname built inside that buffer on success, ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if the pathname won't fit into page. Note that we don't need to check for failure when allocating the buffer in the caller - build_path_from_dentry() will do the right thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 06:36:04 +08:00
free_dentry_path(page);
return ERR_CAST(full_path);
}
cifs_dbg(FYI, "Full path: %s inode = 0x%p\n", full_path, inode);
rc = -EACCES;
/*
* First try Minshall+French Symlinks, if configured
* and fallback to UNIX Extensions Symlinks.
*/
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
rc = query_mf_symlink(xid, tcon, cifs_sb, full_path,
&target_path);
if (rc != 0 && server->ops->query_symlink) {
struct cifsInodeInfo *cifsi = CIFS_I(inode);
bool reparse_point = false;
if (cifsi->cifsAttrs & ATTR_REPARSE)
reparse_point = true;
rc = server->ops->query_symlink(xid, tcon, cifs_sb, full_path,
&target_path, reparse_point);
}
cifs: allocate buffer in the caller of build_path_from_dentry() build_path_from_dentry() open-codes dentry_path_raw(). The reason we can't use dentry_path_raw() in there (and postprocess the result as needed) is that the callers of build_path_from_dentry() expect that the object to be freed on cleanup and the string to be used are at the same address. That's painful, since the path is naturally built end-to-beginning - we start at the leaf and go through the ancestors, accumulating the pathname. Life would be easier if we left the buffer allocation to callers. It wouldn't be exact-sized buffer, but none of the callers keep the result for long - it's always freed before the caller returns. So there's no need to do exact-sized allocation; better use __getname()/__putname(), same as we do for pathname arguments of syscalls. What's more, there's no need to do allocation under spinlocks, so GFP_ATOMIC is not needed. Next patch will replace the open-coded dentry_path_raw() (in build_path_from_dentry_optional_prefix()) with calling the real thing. This patch only introduces wrappers for allocating/freeing the buffers and switches to new calling conventions: build_path_from_dentry(dentry, buf) expects buf to be address of a page-sized object or NULL, return value is a pathname built inside that buffer on success, ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if the pathname won't fit into page. Note that we don't need to check for failure when allocating the buffer in the caller - build_path_from_dentry() will do the right thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 06:36:04 +08:00
free_dentry_path(page);
free_xid(xid);
cifs_put_tlink(tlink);
if (rc != 0) {
kfree(target_path);
return ERR_PTR(rc);
}
set_delayed_call(done, kfree_link, target_path);
return target_path;
}
int
cifs_symlink(struct user_namespace *mnt_userns, struct inode *inode,
struct dentry *direntry, const char *symname)
{
int rc = -EOPNOTSUPP;
unsigned int xid;
struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
struct tcon_link *tlink;
struct cifs_tcon *pTcon;
cifs: allocate buffer in the caller of build_path_from_dentry() build_path_from_dentry() open-codes dentry_path_raw(). The reason we can't use dentry_path_raw() in there (and postprocess the result as needed) is that the callers of build_path_from_dentry() expect that the object to be freed on cleanup and the string to be used are at the same address. That's painful, since the path is naturally built end-to-beginning - we start at the leaf and go through the ancestors, accumulating the pathname. Life would be easier if we left the buffer allocation to callers. It wouldn't be exact-sized buffer, but none of the callers keep the result for long - it's always freed before the caller returns. So there's no need to do exact-sized allocation; better use __getname()/__putname(), same as we do for pathname arguments of syscalls. What's more, there's no need to do allocation under spinlocks, so GFP_ATOMIC is not needed. Next patch will replace the open-coded dentry_path_raw() (in build_path_from_dentry_optional_prefix()) with calling the real thing. This patch only introduces wrappers for allocating/freeing the buffers and switches to new calling conventions: build_path_from_dentry(dentry, buf) expects buf to be address of a page-sized object or NULL, return value is a pathname built inside that buffer on success, ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if the pathname won't fit into page. Note that we don't need to check for failure when allocating the buffer in the caller - build_path_from_dentry() will do the right thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 06:36:04 +08:00
const char *full_path;
void *page;
struct inode *newinode = NULL;
if (unlikely(cifs_forced_shutdown(cifs_sb)))
return -EIO;
page = alloc_dentry_path();
if (!page)
return -ENOMEM;
xid = get_xid();
tlink = cifs_sb_tlink(cifs_sb);
if (IS_ERR(tlink)) {
rc = PTR_ERR(tlink);
goto symlink_exit;
}
pTcon = tlink_tcon(tlink);
cifs: allocate buffer in the caller of build_path_from_dentry() build_path_from_dentry() open-codes dentry_path_raw(). The reason we can't use dentry_path_raw() in there (and postprocess the result as needed) is that the callers of build_path_from_dentry() expect that the object to be freed on cleanup and the string to be used are at the same address. That's painful, since the path is naturally built end-to-beginning - we start at the leaf and go through the ancestors, accumulating the pathname. Life would be easier if we left the buffer allocation to callers. It wouldn't be exact-sized buffer, but none of the callers keep the result for long - it's always freed before the caller returns. So there's no need to do exact-sized allocation; better use __getname()/__putname(), same as we do for pathname arguments of syscalls. What's more, there's no need to do allocation under spinlocks, so GFP_ATOMIC is not needed. Next patch will replace the open-coded dentry_path_raw() (in build_path_from_dentry_optional_prefix()) with calling the real thing. This patch only introduces wrappers for allocating/freeing the buffers and switches to new calling conventions: build_path_from_dentry(dentry, buf) expects buf to be address of a page-sized object or NULL, return value is a pathname built inside that buffer on success, ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if the pathname won't fit into page. Note that we don't need to check for failure when allocating the buffer in the caller - build_path_from_dentry() will do the right thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 06:36:04 +08:00
full_path = build_path_from_dentry(direntry, page);
if (IS_ERR(full_path)) {
rc = PTR_ERR(full_path);
goto symlink_exit;
}
cifs_dbg(FYI, "Full path: %s\n", full_path);
cifs_dbg(FYI, "symname is %s\n", symname);
/* BB what if DFS and this volume is on different share? BB */
if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_MF_SYMLINKS)
rc = create_mf_symlink(xid, pTcon, cifs_sb, full_path, symname);
#ifdef CONFIG_CIFS_ALLOW_INSECURE_LEGACY
else if (pTcon->unix_ext)
rc = CIFSUnixCreateSymLink(xid, pTcon, full_path, symname,
cifs_sb->local_nls,
cifs_remap(cifs_sb));
#endif /* CONFIG_CIFS_ALLOW_INSECURE_LEGACY */
/* else
rc = CIFSCreateReparseSymLink(xid, pTcon, fromName, toName,
cifs_sb_target->local_nls); */
if (rc == 0) {
if (pTcon->posix_extensions)
rc = smb311_posix_get_inode_info(&newinode, full_path, inode->i_sb, xid);
else if (pTcon->unix_ext)
rc = cifs_get_inode_info_unix(&newinode, full_path,
inode->i_sb, xid);
else
rc = cifs_get_inode_info(&newinode, full_path, NULL,
inode->i_sb, xid, NULL);
if (rc != 0) {
cifs_dbg(FYI, "Create symlink ok, getinodeinfo fail rc = %d\n",
rc);
} else {
d_instantiate(direntry, newinode);
}
}
symlink_exit:
cifs: allocate buffer in the caller of build_path_from_dentry() build_path_from_dentry() open-codes dentry_path_raw(). The reason we can't use dentry_path_raw() in there (and postprocess the result as needed) is that the callers of build_path_from_dentry() expect that the object to be freed on cleanup and the string to be used are at the same address. That's painful, since the path is naturally built end-to-beginning - we start at the leaf and go through the ancestors, accumulating the pathname. Life would be easier if we left the buffer allocation to callers. It wouldn't be exact-sized buffer, but none of the callers keep the result for long - it's always freed before the caller returns. So there's no need to do exact-sized allocation; better use __getname()/__putname(), same as we do for pathname arguments of syscalls. What's more, there's no need to do allocation under spinlocks, so GFP_ATOMIC is not needed. Next patch will replace the open-coded dentry_path_raw() (in build_path_from_dentry_optional_prefix()) with calling the real thing. This patch only introduces wrappers for allocating/freeing the buffers and switches to new calling conventions: build_path_from_dentry(dentry, buf) expects buf to be address of a page-sized object or NULL, return value is a pathname built inside that buffer on success, ERR_PTR(-ENOMEM) if buf is NULL and ERR_PTR(-ENAMETOOLONG) if the pathname won't fit into page. Note that we don't need to check for failure when allocating the buffer in the caller - build_path_from_dentry() will do the right thing. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Steve French <stfrench@microsoft.com>
2021-03-06 06:36:04 +08:00
free_dentry_path(page);
cifs_put_tlink(tlink);
free_xid(xid);
return rc;
}