[PATCH 01/12] cifs: Fix struct FILE_ALL_INFO

[PATCH 01/12] cifs: Fix struct FILE_ALL_INFO

[Pali Rohár]

struct FILE_ALL_INFO for level 263 (0x107) used by QPathInfo does not have
any IndexNumber, AccessFlags, IndexNumber1, CurrentByteOffset, Mode or
AlignmentRequirement members. So remove all of them.

Also adjust code in move_cifs_info_to_smb2() function which convers struct
FILE_ALL_INFO to struct smb2_file_all_info.

Fixed content of struct FILE_ALL_INFO was verified that is correct against:
* [MS-CIFS] section 2.2.8.3.10 SMB_QUERY_FILE_ALL_INFO
* Samba server implementation of trans2 query file/path for level 263
* Packet structure tests against Windows SMB servers

This change fixes CIFSSMBQFileInfo() and CIFSSMBQPathInfo() functions which
directly copy received FILE_ALL_INFO network buffers into kernel structures
of FILE_ALL_INFO type.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/cifsglob.h | 12 +++++++-----
 fs/smb/client/cifspdu.h  |  6 ------
 2 files changed, 7 insertions(+), 11 deletions(-)

diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h
index 1338b3473ef3..82e819f9d24e 100644
--- a/fs/smb/client/cifsglob.h
+++ b/fs/smb/client/cifsglob.h
@@ -2216,11 +2216,13 @@ static inline size_t ntlmssp_workstation_name_size(const struct cifs_ses *ses)
 
 static inline void move_cifs_info_to_smb2(struct smb2_file_all_info *dst, const FILE_ALL_INFO *src)
 {
-	memcpy(dst, src, (size_t)((u8 *)&src->AccessFlags - (u8 *)src));
-	dst->AccessFlags = src->AccessFlags;
-	dst->CurrentByteOffset = src->CurrentByteOffset;
-	dst->Mode = src->Mode;
-	dst->AlignmentRequirement = src->AlignmentRequirement;
+	memcpy(dst, src, (size_t)((u8 *)&src->EASize - (u8 *)src));
+	dst->IndexNumber = 0;
+	dst->EASize = src->EASize;
+	dst->AccessFlags = 0;
+	dst->CurrentByteOffset = 0;
+	dst->Mode = 0;
+	dst->AlignmentRequirement = 0;
 	dst->FileNameLength = src->FileNameLength;
 }
 
diff --git a/fs/smb/client/cifspdu.h b/fs/smb/client/cifspdu.h
index 3ad1bb79ea9e..e5e397291da9 100644
--- a/fs/smb/client/cifspdu.h
+++ b/fs/smb/client/cifspdu.h
@@ -2294,13 +2294,7 @@ typedef struct { /* data block encoding of response to level 263 QPathInfo */
 	__u8 DeletePending;
 	__u8 Directory;
 	__u16 Pad2;
-	__le64 IndexNumber;
 	__le32 EASize;
-	__le32 AccessFlags;
-	__u64 IndexNumber1;
-	__le64 CurrentByteOffset;
-	__le32 Mode;
-	__le32 AlignmentRequirement;
 	__le32 FileNameLength;
 	union {
 		char __pad;
-- 
2.20.1

[PATCH 02/12] cifs: Fix calling CIFSFindFirst() for root path without msearch

[Pali Rohár]

To query root path (without msearch wildcard) it is needed to
send pattern "\" instead of "" (empty string).

This allows to use CIFSFindFirst() to query information about root path.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/cifssmb.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/fs/smb/client/cifssmb.c b/fs/smb/client/cifssmb.c
index 604e204e3f57..7c42a0651138 100644
--- a/fs/smb/client/cifssmb.c
+++ b/fs/smb/client/cifssmb.c
@@ -4108,6 +4108,12 @@ CIFSFindFirst(const unsigned int xid, struct cifs_tcon *tcon,
 			pSMB->FileName[name_len] = 0;
 			pSMB->FileName[name_len+1] = 0;
 			name_len += 2;
+		} else if (!searchName[0]) {
+			pSMB->FileName[0] = CIFS_DIR_SEP(cifs_sb);
+			pSMB->FileName[1] = 0;
+			pSMB->FileName[2] = 0;
+			pSMB->FileName[3] = 0;
+			name_len = 4;
 		}
 	} else {
 		name_len = copy_path_name(pSMB->FileName, searchName);
@@ -4119,6 +4125,10 @@ CIFSFindFirst(const unsigned int xid, struct cifs_tcon *tcon,
 			pSMB->FileName[name_len] = '*';
 			pSMB->FileName[name_len+1] = 0;
 			name_len += 2;
+		} else if (!searchName[0]) {
+			pSMB->FileName[0] = CIFS_DIR_SEP(cifs_sb);
+			pSMB->FileName[1] = 0;
+			name_len = 2;
 		}
 	}
 
-- 
2.20.1

[PATCH 03/12] cifs: Optimize CIFSFindFirst() response when not searching

[Pali Rohár]

When not searching for child entries with msearch wildcard pattern then ask
server just for one output entry. There is no need to ask for more entries
as we are interested only for one search result, as we are doing query on
path.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/cifssmb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/smb/client/cifssmb.c b/fs/smb/client/cifssmb.c
index 7c42a0651138..c0dc404e27b3 100644
--- a/fs/smb/client/cifssmb.c
+++ b/fs/smb/client/cifssmb.c
@@ -4155,7 +4155,7 @@ CIFSFindFirst(const unsigned int xid, struct cifs_tcon *tcon,
 	pSMB->SearchAttributes =
 	    cpu_to_le16(ATTR_READONLY | ATTR_HIDDEN | ATTR_SYSTEM |
 			ATTR_DIRECTORY);
-	pSMB->SearchCount = cpu_to_le16(CIFSMaxBufSize/sizeof(FILE_UNIX_INFO));
+	pSMB->SearchCount = cpu_to_le16(msearch ? CIFSMaxBufSize/sizeof(FILE_UNIX_INFO) : 1);
 	pSMB->SearchFlags = cpu_to_le16(search_flags);
 	pSMB->InformationLevel = cpu_to_le16(psrch_inf->info_level);
 
-- 
2.20.1

[PATCH 04/12] cifs: Fix and improve cifs_is_path_accessible() function

[Pali Rohár]

Do not call SMBQueryInformation() command for path with SMB wildcard
characters on non-UNICODE connection because server expands wildcards.
Function cifs_is_path_accessible() needs to check if the real path exists
and must not expand wildcard characters.

Do not dynamically allocate memory for small FILE_ALL_INFO structure and
instead allocate it on the stack. This structure is allocated on stack by
all other functions.

When CAP_NT_SMBS was not negotiated then do not issue CIFSSMBQPathInfo()
command. This command returns failure by non-NT Win9x SMB servers, so there
is no need try it. The purpose of cifs_is_path_accessible() function is
just to check if the path is accessible, so SMBQueryInformation() for old
servers is enough.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/smb1ops.c | 26 ++++++++++++++++----------
 1 file changed, 16 insertions(+), 10 deletions(-)

diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c
index d959097ec2d2..bef8e03edf1d 100644
--- a/fs/smb/client/smb1ops.c
+++ b/fs/smb/client/smb1ops.c
@@ -520,21 +520,27 @@ static int
 cifs_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
 			struct cifs_sb_info *cifs_sb, const char *full_path)
 {
-	int rc;
-	FILE_ALL_INFO *file_info;
+	int rc = -EOPNOTSUPP;
+	FILE_ALL_INFO file_info;
 
-	file_info = kmalloc(sizeof(FILE_ALL_INFO), GFP_KERNEL);
-	if (file_info == NULL)
-		return -ENOMEM;
+	if (tcon->ses->capabilities & CAP_NT_SMBS)
+		rc = CIFSSMBQPathInfo(xid, tcon, full_path, &file_info,
+				      0 /* not legacy */, cifs_sb->local_nls,
+				      cifs_remap(cifs_sb));
 
-	rc = CIFSSMBQPathInfo(xid, tcon, full_path, file_info,
-			      0 /* not legacy */, cifs_sb->local_nls,
-			      cifs_remap(cifs_sb));
+	/*
+	 * Non-UNICODE variant of fallback functions below expands wildcards,
+	 * so they cannot be used for querying paths with wildcard characters.
+	 * Therefore for such paths returns -ENOENT as they cannot exist.
+	 */
+	if ((rc == -EOPNOTSUPP || rc == -EINVAL) &&
+	    !(tcon->ses->capabilities & CAP_UNICODE) &&
+	    strpbrk(full_path, "*?\"><"))
+		rc = -ENOENT;
 
 	if (rc == -EOPNOTSUPP || rc == -EINVAL)
-		rc = SMBQueryInformation(xid, tcon, full_path, file_info,
+		rc = SMBQueryInformation(xid, tcon, full_path, &file_info,
 				cifs_sb->local_nls, cifs_remap(cifs_sb));
-	kfree(file_info);
 	return rc;
 }
 
-- 
2.20.1

[PATCH 05/12] cifs: Fix cifs_query_path_info() for Windows NT servers

[Pali Rohár]

For TRANS2 QUERY_PATH_INFO request when the path does not exist, the
Windows NT SMB server returns error response STATUS_OBJECT_NAME_NOT_FOUND
or ERRDOS/ERRbadfile without the SMBFLG_RESPONSE flag set. Similarly it
returns STATUS_DELETE_PENDING when the file is being deleted. And looks
like that any error response from TRANS2 QUERY_PATH_INFO does not have
SMBFLG_RESPONSE flag set.

So relax check in check_smb_hdr() for detecting if the packet is response
for this special case.

This change fixes stat() operation against Windows NT SMB servers and also
all operations which depends on -ENOENT result from stat like creat() or
mkdir().

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/misc.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/fs/smb/client/misc.c b/fs/smb/client/misc.c
index 4373dd64b66d..5122f3895dfc 100644
--- a/fs/smb/client/misc.c
+++ b/fs/smb/client/misc.c
@@ -323,6 +323,14 @@ check_smb_hdr(struct smb_hdr *smb)
 	if (smb->Command == SMB_COM_LOCKING_ANDX)
 		return 0;
 
+	/*
+	 * Windows NT server returns error resposne (e.g. STATUS_DELETE_PENDING
+	 * or STATUS_OBJECT_NAME_NOT_FOUND or ERRDOS/ERRbadfile or any other)
+	 * for some TRANS2 requests without the RESPONSE flag set in header.
+	 */
+	if (smb->Command == SMB_COM_TRANSACTION2 && smb->Status.CifsError != 0)
+		return 0;
+
 	cifs_dbg(VFS, "Server sent request, not response. mid=%u\n",
 		 get_mid(smb));
 	return 1;
-- 
2.20.1

[PATCH 06/12] cifs: Fix and improve cifs_query_path_info() and cifs_query_file_info()

[Pali Rohár]

When CAP_NT_SMBS was not negotiated then do not issue CIFSSMBQPathInfo()
and CIFSSMBQFileInfo() commands. CIFSSMBQPathInfo() is not supported by
non-NT Win9x SMB server and CIFSSMBQFileInfo() returns from Win9x SMB
server bogus data in Attributes field (for example lot of files are marked
as reparse points, even Win9x does not support them and read-only bit is
not marked for read-only files). Correct information is returned by
CIFSFindFirst() or SMBQueryInformation() command.

So as a fallack in cifs_query_path_info() function use CIFSFindFirst() with
SMB_FIND_FILE_FULL_DIRECTORY_INFO level which is supported by both NT and
non-NT servers and as a last option use SMBQueryInformation() as it was
before.

And in function cifs_query_file_info() immediately returns -EOPNOTSUPP when
not communicating with NT server. Client then revalidate inode entry by the
cifs_query_path_info() call, which is working fine. So fstat() syscall on
already opened file will receive correct information.

Note that both fallback functions in non-UNICODE mode expands wildcards.
Therefore those fallback functions cannot be used on paths which contain
SMB wildcard characters (* ? " > <).

CIFSFindFirst() returns all 4 time attributes as opposite of
SMBQueryInformation() which returns only one.

With this change it is possible to query all 4 times attributes from Win9x
server and at the same time, client minimize sending of unsupported
commands to server.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/smb1ops.c | 78 +++++++++++++++++++++++++++++++++++++----
 1 file changed, 71 insertions(+), 7 deletions(-)

diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c
index bef8e03edf1d..b0813106df16 100644
--- a/fs/smb/client/smb1ops.c
+++ b/fs/smb/client/smb1ops.c
@@ -550,19 +550,76 @@ static int cifs_query_path_info(const unsigned int xid,
 				const char *full_path,
 				struct cifs_open_info_data *data)
 {
-	int rc;
+	int rc = -EOPNOTSUPP;
 	FILE_ALL_INFO fi = {};
+	FILE_FULL_DIRECTORY_INFO *di;
+	struct cifs_search_info search_info = {};
 
 	data->reparse_point = false;
 	data->adjust_tz = false;
 
-	/* could do find first instead but this returns more info */
-	rc = CIFSSMBQPathInfo(xid, tcon, full_path, &fi, 0 /* not legacy */, cifs_sb->local_nls,
-			      cifs_remap(cifs_sb));
 	/*
-	 * BB optimize code so we do not make the above call when server claims
-	 * no NT SMB support and the above call failed at least once - set flag
-	 * in tcon or mount.
+	 * First try CIFSSMBQPathInfo() function which returns more info
+	 * (NumberOfLinks) than CIFSFindFirst() fallback function.
+	 * Some servers like Win9x do not support SMB_QUERY_FILE_ALL_INFO over
+	 * TRANS2_QUERY_PATH_INFORMATION, but supports it with filehandle over
+	 * TRANS2_QUERY_FILE_INFORMATION (function CIFSSMBQFileInfo(). But SMB
+	 * Open command on non-NT servers works only for files, does not work
+	 * for directories. And moreover Win9x SMB server returns bogus data in
+	 * SMB_QUERY_FILE_ALL_INFO Attributes field. So for non-NT servers,
+	 * do not even use CIFSSMBQPathInfo() or CIFSSMBQFileInfo() function.
+	 */
+	if (tcon->ses->capabilities & CAP_NT_SMBS)
+		rc = CIFSSMBQPathInfo(xid, tcon, full_path, &fi, 0 /* not legacy */,
+				      cifs_sb->local_nls, cifs_remap(cifs_sb));
+
+	/*
+	 * Non-UNICODE variant of fallback functions below expands wildcards,
+	 * so they cannot be used for querying paths with wildcard characters.
+	 * Therefore for such paths returns -ENOENT as they cannot exist.
+	 */
+	if ((rc == -EOPNOTSUPP || rc == -EINVAL) &&
+	    !(tcon->ses->capabilities & CAP_UNICODE) &&
+	    strpbrk(full_path, "*?\"><"))
+		rc = -ENOENT;
+
+	/*
+	 * Then fallback to CIFSFindFirst() which works also with non-NT servers
+	 * but does not does not provide NumberOfLinks.
+	 */
+	if (rc == -EOPNOTSUPP || rc == -EINVAL) {
+		search_info.info_level = SMB_FIND_FILE_FULL_DIRECTORY_INFO;
+		rc = CIFSFindFirst(xid, tcon, full_path, cifs_sb, NULL,
+				   CIFS_SEARCH_CLOSE_ALWAYS | CIFS_SEARCH_CLOSE_AT_END,
+				   &search_info, false);
+		if (rc == 0) {
+			di = (FILE_FULL_DIRECTORY_INFO *)search_info.srch_entries_start;
+			fi.CreationTime = di->CreationTime;
+			fi.LastAccessTime = di->LastAccessTime;
+			fi.LastWriteTime = di->LastWriteTime;
+			fi.ChangeTime = di->ChangeTime;
+			fi.Attributes = di->ExtFileAttributes;
+			fi.AllocationSize = di->AllocationSize;
+			fi.EndOfFile = di->EndOfFile;
+			fi.EASize = di->EaSize;
+			fi.NumberOfLinks = cpu_to_le32(1);
+			fi.DeletePending = 0;
+			fi.Directory = !!(le32_to_cpu(di->ExtFileAttributes) & ATTR_DIRECTORY);
+			cifs_buf_release(search_info.ntwrk_buf_start);
+		} else if (!full_path[0]) {
+			/*
+			 * CIFSFindFirst() does not work on root path if the
+			 * root path was exported on the server from the top
+			 * level path (drive letter).
+			 */
+			rc = -EOPNOTSUPP;
+		}
+	}
+
+	/*
+	 * If everything failed then fallback to the legacy SMB command
+	 * SMB_COM_QUERY_INFORMATION which works with all servers, but
+	 * provide just few information.
 	 */
 	if ((rc == -EOPNOTSUPP) || (rc == -EINVAL)) {
 		rc = SMBQueryInformation(xid, tcon, full_path, &fi, cifs_sb->local_nls,
@@ -646,6 +703,13 @@ static int cifs_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
 	int rc;
 	FILE_ALL_INFO fi = {};
 
+	/*
+	 * CIFSSMBQFileInfo() for non-NT servers returns bogus data in
+	 * Attributes fields. So do not use this command for non-NT servers.
+	 */
+	if (!(tcon->ses->capabilities & CAP_NT_SMBS))
+		return -EOPNOTSUPP;
+
 	if (cfile->symlink_target) {
 		data->symlink_target = kstrdup(cfile->symlink_target, GFP_KERNEL);
 		if (!data->symlink_target)
-- 
2.20.1

[PATCH 07/12] cifs: Improve SMB1 stat() to work also for paths in DELETE_PENDING state

[Pali Rohár]

Windows NT SMB server may return -EBUSY (STATUS_DELETE_PENDING) from
CIFSSMBQPathInfo() function for files which are in DELETE_PENDING state.
When this happens, it is still possible to use CIFSFindFirst() fallback.
So allow to use CIFSFindFirst() fallback also for -EBUSY error.

This change fixed stat() to work also against Windows Server 2022 for files
in DELETE_PENDING state.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/smb1ops.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c
index b0813106df16..a7a846260736 100644
--- a/fs/smb/client/smb1ops.c
+++ b/fs/smb/client/smb1ops.c
@@ -578,7 +578,7 @@ static int cifs_query_path_info(const unsigned int xid,
 	 * so they cannot be used for querying paths with wildcard characters.
 	 * Therefore for such paths returns -ENOENT as they cannot exist.
 	 */
-	if ((rc == -EOPNOTSUPP || rc == -EINVAL) &&
+	if ((rc == -EOPNOTSUPP || rc == -EINVAL || rc == -EBUSY) &&
 	    !(tcon->ses->capabilities & CAP_UNICODE) &&
 	    strpbrk(full_path, "*?\"><"))
 		rc = -ENOENT;
@@ -587,7 +587,7 @@ static int cifs_query_path_info(const unsigned int xid,
 	 * Then fallback to CIFSFindFirst() which works also with non-NT servers
 	 * but does not does not provide NumberOfLinks.
 	 */
-	if (rc == -EOPNOTSUPP || rc == -EINVAL) {
+	if (rc == -EOPNOTSUPP || rc == -EINVAL || rc == -EBUSY) {
 		search_info.info_level = SMB_FIND_FILE_FULL_DIRECTORY_INFO;
 		rc = CIFSFindFirst(xid, tcon, full_path, cifs_sb, NULL,
 				   CIFS_SEARCH_CLOSE_ALWAYS | CIFS_SEARCH_CLOSE_AT_END,
-- 
2.20.1

[PATCH 08/12] cifs: Remove code for querying FILE_INFO_STANDARD via CIFSSMBQPathInfo()

[Pali Rohár]

Querying FILE_INFO_STANDARD structure via SMB_QUERY_FILE_ALL_INFO level
over TRANS2_QUERY_PATH_INFORMATION or TRANS2_QUERY_FILE_INFORMATION command
(implemented in CIFSSMBQPathInfo() when called with argument legacy=true)
is mostly unusable.

Win9x SMB server returns over those commands the FILE_INFO_STANDARD
structure with swapped TIME and DATE fields, compared with [MS-CIFS] spec
and Samba server implementation. Therefore this command cannot be used
unless we know against which server implementation we are connected.

There are already two fallback mechanisms for querying information about
path which are working correctly against Samba, NT and Win9x servers:
CIFSFindFirst() and SMBQueryInformation() commands.

So remove TRANS2_QUERY_PATH_INFORMATION/SMB_QUERY_FILE_ALL_INFO code from
CIFSSMBQPathInfo() function, when the function is called with legacy=true.
Note that there is no use of CIFSSMBQPathInfo(legacy=true) anymore.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/cifsproto.h |  1 -
 fs/smb/client/cifssmb.c   | 22 +++-------------------
 fs/smb/client/smb1ops.c   |  4 ++--
 3 files changed, 5 insertions(+), 22 deletions(-)

diff --git a/fs/smb/client/cifsproto.h b/fs/smb/client/cifsproto.h
index ea8a0ecce9dc..52548238b467 100644
--- a/fs/smb/client/cifsproto.h
+++ b/fs/smb/client/cifsproto.h
@@ -351,7 +351,6 @@ extern int CIFSSMBQFileInfo(const unsigned int xid, struct cifs_tcon *tcon,
 			u16 netfid, FILE_ALL_INFO *pFindData);
 extern int CIFSSMBQPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 			    const char *search_Name, FILE_ALL_INFO *data,
-			    int legacy /* whether to use old info level */,
 			    const struct nls_table *nls_codepage, int remap);
 extern int SMBQueryInformation(const unsigned int xid, struct cifs_tcon *tcon,
 			       const char *search_name, FILE_ALL_INFO *data,
diff --git a/fs/smb/client/cifssmb.c b/fs/smb/client/cifssmb.c
index c0dc404e27b3..c88b6ea7c00a 100644
--- a/fs/smb/client/cifssmb.c
+++ b/fs/smb/client/cifssmb.c
@@ -3816,7 +3816,6 @@ CIFSSMBQFileInfo(const unsigned int xid, struct cifs_tcon *tcon,
 int
 CIFSSMBQPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 		 const char *search_name, FILE_ALL_INFO *data,
-		 int legacy /* old style infolevel */,
 		 const struct nls_table *nls_codepage, int remap)
 {
 	/* level 263 SMB_QUERY_FILE_ALL_INFO */
@@ -3864,10 +3863,7 @@ CIFSSMBQPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 	byte_count = params + 1 /* pad */ ;
 	pSMB->TotalParameterCount = cpu_to_le16(params);
 	pSMB->ParameterCount = pSMB->TotalParameterCount;
-	if (legacy)
-		pSMB->InformationLevel = cpu_to_le16(SMB_INFO_STANDARD);
-	else
-		pSMB->InformationLevel = cpu_to_le16(SMB_QUERY_FILE_ALL_INFO);
+	pSMB->InformationLevel = cpu_to_le16(SMB_QUERY_FILE_ALL_INFO);
 	pSMB->Reserved4 = 0;
 	inc_rfc1001_len(pSMB, byte_count);
 	pSMB->ByteCount = cpu_to_le16(byte_count);
@@ -3881,25 +3877,13 @@ CIFSSMBQPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 
 		if (rc) /* BB add auto retry on EOPNOTSUPP? */
 			rc = -EIO;
-		else if (!legacy && get_bcc(&pSMBr->hdr) < 40)
+		else if (get_bcc(&pSMBr->hdr) < 40)
 			rc = -EIO;	/* bad smb */
-		else if (legacy && get_bcc(&pSMBr->hdr) < 24)
-			rc = -EIO;  /* 24 or 26 expected but we do not read
-					last field */
 		else if (data) {
 			int size;
 			__u16 data_offset = le16_to_cpu(pSMBr->t2.DataOffset);
 
-			/*
-			 * On legacy responses we do not read the last field,
-			 * EAsize, fortunately since it varies by subdialect and
-			 * also note it differs on Set vs Get, ie two bytes or 4
-			 * bytes depending but we don't care here.
-			 */
-			if (legacy)
-				size = sizeof(FILE_INFO_STANDARD);
-			else
-				size = sizeof(FILE_ALL_INFO);
+			size = sizeof(FILE_ALL_INFO);
 			memcpy((char *) data, (char *) &pSMBr->hdr.Protocol +
 			       data_offset, size);
 		} else
diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c
index a7a846260736..49b5b75ef2f0 100644
--- a/fs/smb/client/smb1ops.c
+++ b/fs/smb/client/smb1ops.c
@@ -525,7 +525,7 @@ cifs_is_path_accessible(const unsigned int xid, struct cifs_tcon *tcon,
 
 	if (tcon->ses->capabilities & CAP_NT_SMBS)
 		rc = CIFSSMBQPathInfo(xid, tcon, full_path, &file_info,
-				      0 /* not legacy */, cifs_sb->local_nls,
+				      cifs_sb->local_nls,
 				      cifs_remap(cifs_sb));
 
 	/*
@@ -570,7 +570,7 @@ static int cifs_query_path_info(const unsigned int xid,
 	 * do not even use CIFSSMBQPathInfo() or CIFSSMBQFileInfo() function.
 	 */
 	if (tcon->ses->capabilities & CAP_NT_SMBS)
-		rc = CIFSSMBQPathInfo(xid, tcon, full_path, &fi, 0 /* not legacy */,
+		rc = CIFSSMBQPathInfo(xid, tcon, full_path, &fi,
 				      cifs_sb->local_nls, cifs_remap(cifs_sb));
 
 	/*
-- 
2.20.1

[PATCH 09/12] cifs: Allow fallback code in smb_set_file_info() also for directories

[Pali Rohár]

On NT systems, it is possible to do SMB open call also for directories.
Open argument CREATE_NOT_DIR disallows opening directories. So in fallback
code path in smb_set_file_info() remove CREATE_NOT_DIR restriction to allow
it also for directories.

Similar fallback is implemented also in CIFSSMBSetPathInfoFB() function and
this function already allows to call operation for directories.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/smb1ops.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c
index 49b5b75ef2f0..62f4e1081ea4 100644
--- a/fs/smb/client/smb1ops.c
+++ b/fs/smb/client/smb1ops.c
@@ -915,7 +915,7 @@ smb_set_file_info(struct inode *inode, const char *full_path,
 		.tcon = tcon,
 		.cifs_sb = cifs_sb,
 		.desired_access = SYNCHRONIZE | FILE_WRITE_ATTRIBUTES,
-		.create_options = cifs_create_options(cifs_sb, CREATE_NOT_DIR),
+		.create_options = cifs_create_options(cifs_sb, 0),
 		.disposition = FILE_OPEN,
 		.path = full_path,
 		.fid = &fid,
-- 
2.20.1

[PATCH 10/12] cifs: Fix changing times and read-only attr over SMB1 smb_set_file_info() function

[Pali Rohár]

Function CIFSSMBSetPathInfo() is not supported by non-NT servers and
returns error. Fallback code via open filehandle and CIFSSMBSetFileInfo()
does not work neither because CIFS_open() works also only on NT server.

Therefore currently the whole smb_set_file_info() function as a SMB1
callback for the ->set_file_info() does not work with older non-NT SMB
servers, like Win9x and others.

This change implements fallback code in smb_set_file_info() which will
works with any server and allows to change time values and also to set or
clear read-only attributes.

To make existing fallback code via CIFSSMBSetFileInfo() working with also
non-NT servers, it is needed to change open function from CIFS_open()
(which is NT specific) to cifs_open_file() which works with any server
(this is just a open wrapper function which choose the correct open
function supported by the server).

CIFSSMBSetFileInfo() is working also on non-NT servers, but zero time
values are not treated specially. So first it is needed to fill all time
values if some of them are missing, via cifs_query_path_info() call.

There is another issue, opening file in write-mode (needed for changing
attributes) is not possible when the file has read-only attribute set.
The only option how to clear read-only attribute is via SMB_COM_SETATTR
command. And opening directory is not possible neither and here the
SMB_COM_SETATTR command is the only option how to change attributes.
And CIFSSMBSetFileInfo() does not honor setting read-only attribute, so
for setting is also needed to use SMB_COM_SETATTR command.

Existing code in cifs_query_path_info() is already using SMB_COM_GETATTR as
a fallback code path (function SMBQueryInformation()), so introduce a new
function SMBSetInformation which will implement SMB_COM_SETATTR command.

My testing showed that Windows XP SMB1 client is also using SMB_COM_SETATTR
command for setting or clearing read-only attribute against non-NT server.
So this can prove that this is the correct way how to do it.

With this change it is possible set all 4 time values and all attributes,
including clearing and setting read-only bit on non-NT SMB servers.
Tested against Win98 SMB1 server.

This change fixes "touch" command which was failing when called on existing
file. And fixes also "chmod +w" and "chmod -w" commands which were also
failing (as they are changing read-only attribute).

Note that this change depends on following change
"cifs: Improve cifs_query_path_info() and cifs_query_file_info()"
as it require to query all 4 time attribute values.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/cifspdu.h   |   3 +-
 fs/smb/client/cifsproto.h |   4 ++
 fs/smb/client/cifssmb.c   |  57 +++++++++++++++++++
 fs/smb/client/smb1ops.c   | 112 +++++++++++++++++++++++++++++++++++---
 4 files changed, 165 insertions(+), 11 deletions(-)

diff --git a/fs/smb/client/cifspdu.h b/fs/smb/client/cifspdu.h
index e5e397291da9..fd114fcb1320 100644
--- a/fs/smb/client/cifspdu.h
+++ b/fs/smb/client/cifspdu.h
@@ -1270,8 +1270,7 @@ typedef struct smb_com_query_information_rsp {
 typedef struct smb_com_setattr_req {
 	struct smb_hdr hdr; /* wct = 8 */
 	__le16 attr;
-	__le16 time_low;
-	__le16 time_high;
+	__le32 last_write_time;
 	__le16 reserved[5]; /* must be zero */
 	__u16  ByteCount;
 	__u8   BufferFormat; /* 4 = ASCII */
diff --git a/fs/smb/client/cifsproto.h b/fs/smb/client/cifsproto.h
index 52548238b467..8f77b6d5c6ca 100644
--- a/fs/smb/client/cifsproto.h
+++ b/fs/smb/client/cifsproto.h
@@ -392,6 +392,10 @@ extern int CIFSSMBQFSUnixInfo(const unsigned int xid, struct cifs_tcon *tcon);
 extern int CIFSSMBQFSPosixInfo(const unsigned int xid, struct cifs_tcon *tcon,
 			struct kstatfs *FSData);
 
+extern int SMBSetInformation(const unsigned int xid, struct cifs_tcon *tcon,
+			     const char *fileName, __le32 attributes, __le64 write_time,
+			     const struct nls_table *nls_codepage,
+			     struct cifs_sb_info *cifs_sb);
 extern int CIFSSMBSetPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 			const char *fileName, const FILE_BASIC_INFO *data,
 			const struct nls_table *nls_codepage,
diff --git a/fs/smb/client/cifssmb.c b/fs/smb/client/cifssmb.c
index c88b6ea7c00a..acbdb6d92306 100644
--- a/fs/smb/client/cifssmb.c
+++ b/fs/smb/client/cifssmb.c
@@ -5292,6 +5292,63 @@ CIFSSMBSetFileSize(const unsigned int xid, struct cifs_tcon *tcon,
 	return rc;
 }
 
+int
+SMBSetInformation(const unsigned int xid, struct cifs_tcon *tcon,
+		  const char *fileName, __le32 attributes, __le64 write_time,
+		  const struct nls_table *nls_codepage,
+		  struct cifs_sb_info *cifs_sb)
+{
+	SETATTR_REQ *pSMB;
+	SETATTR_RSP *pSMBr;
+	struct timespec64 ts;
+	int bytes_returned;
+	int name_len;
+	int rc;
+
+	cifs_dbg(FYI, "In SMBSetInformation path %s\n", fileName);
+
+retry:
+	rc = smb_init(SMB_COM_SETATTR, 8, tcon, (void **) &pSMB,
+		      (void **) &pSMBr);
+	if (rc)
+		return rc;
+
+	if (pSMB->hdr.Flags2 & SMBFLG2_UNICODE) {
+		name_len =
+			cifsConvertToUTF16((__le16 *) pSMB->fileName,
+					   fileName, PATH_MAX, nls_codepage,
+					   cifs_remap(cifs_sb));
+		name_len++;     /* trailing null */
+		name_len *= 2;
+	} else {
+		name_len = copy_path_name(pSMB->fileName, fileName);
+	}
+	/* Only few attributes can be set by this command, others are not accepted by Win9x. */
+	pSMB->attr = cpu_to_le16(le32_to_cpu(attributes) &
+			(ATTR_READONLY | ATTR_HIDDEN | ATTR_SYSTEM | ATTR_ARCHIVE));
+	/* Zero write time value (in both NT and SETATTR formats) means to not change it. */
+	if (le64_to_cpu(write_time) != 0) {
+		ts = cifs_NTtimeToUnix(le64_to_cpu(write_time));
+		pSMB->last_write_time = cpu_to_le32(ts.tv_sec);
+	}
+	pSMB->BufferFormat = 0x04;
+	name_len++; /* account for buffer type byte */
+	inc_rfc1001_len(pSMB, (__u16)name_len);
+	pSMB->ByteCount = cpu_to_le16(name_len);
+
+	rc = SendReceive(xid, tcon->ses, (struct smb_hdr *) pSMB,
+			 (struct smb_hdr *) pSMBr, &bytes_returned, 0);
+	if (rc)
+		cifs_dbg(FYI, "Send error in SMBSetInformation = %d\n", rc);
+
+	cifs_buf_release(pSMB);
+
+	if (rc == -EAGAIN)
+		goto retry;
+
+	return rc;
+}
+
 /* Some legacy servers such as NT4 require that the file times be set on
    an open handle, rather than by pathname - this is awkward due to
    potential access conflicts on the open, but it is unavoidable for these
diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c
index 62f4e1081ea4..33af1a6ab348 100644
--- a/fs/smb/client/smb1ops.c
+++ b/fs/smb/client/smb1ops.c
@@ -880,6 +880,9 @@ smb_set_file_info(struct inode *inode, const char *full_path,
 	struct cifs_fid fid;
 	struct cifs_open_parms oparms;
 	struct cifsFileInfo *open_file;
+	FILE_BASIC_INFO new_buf;
+	struct cifs_open_info_data query_data;
+	__le64 write_time = buf->LastWriteTime;
 	struct cifsInodeInfo *cinode = CIFS_I(inode);
 	struct cifs_sb_info *cifs_sb = CIFS_SB(inode->i_sb);
 	struct tcon_link *tlink = NULL;
@@ -887,20 +890,58 @@ smb_set_file_info(struct inode *inode, const char *full_path,
 
 	/* if the file is already open for write, just use that fileid */
 	open_file = find_writable_file(cinode, FIND_WR_FSUID_ONLY);
+
 	if (open_file) {
 		fid.netfid = open_file->fid.netfid;
 		netpid = open_file->pid;
 		tcon = tlink_tcon(open_file->tlink);
-		goto set_via_filehandle;
+	} else {
+		tlink = cifs_sb_tlink(cifs_sb);
+		if (IS_ERR(tlink)) {
+			rc = PTR_ERR(tlink);
+			tlink = NULL;
+			goto out;
+		}
+		tcon = tlink_tcon(tlink);
 	}
 
-	tlink = cifs_sb_tlink(cifs_sb);
-	if (IS_ERR(tlink)) {
-		rc = PTR_ERR(tlink);
-		tlink = NULL;
-		goto out;
+	/*
+	 * Non-NT servers interprets zero time value in SMB_SET_FILE_BASIC_INFO
+	 * over TRANS2_SET_FILE_INFORMATION as a valid time value. NT servers
+	 * interprets zero time value as do not change existing value on server.
+	 * API of ->set_file_info() callback expects that zero time value has
+	 * the NT meaning - do not change. Therefore if server is non-NT and
+	 * some time values in "buf" are zero, then fetch missing time values.
+	 */
+	if (!(tcon->ses->capabilities & CAP_NT_SMBS) &&
+	    (!buf->CreationTime || !buf->LastAccessTime ||
+	     !buf->LastWriteTime || !buf->ChangeTime)) {
+		rc = cifs_query_path_info(xid, tcon, cifs_sb, full_path, &query_data);
+		if (rc) {
+			if (open_file) {
+				cifsFileInfo_put(open_file);
+				open_file = NULL;
+			}
+			goto out;
+		}
+		/*
+		 * Original write_time from buf->LastWriteTime is preserved
+		 * as SMBSetInformation() interprets zero as do not change.
+		 */
+		new_buf = *buf;
+		buf = &new_buf;
+		if (!buf->CreationTime)
+			buf->CreationTime = query_data.fi.CreationTime;
+		if (!buf->LastAccessTime)
+			buf->LastAccessTime = query_data.fi.LastAccessTime;
+		if (!buf->LastWriteTime)
+			buf->LastWriteTime = query_data.fi.LastWriteTime;
+		if (!buf->ChangeTime)
+			buf->ChangeTime = query_data.fi.ChangeTime;
 	}
-	tcon = tlink_tcon(tlink);
+
+	if (open_file)
+		goto set_via_filehandle;
 
 	rc = CIFSSMBSetPathInfo(xid, tcon, full_path, buf, cifs_sb->local_nls,
 				cifs_sb);
@@ -921,8 +962,45 @@ smb_set_file_info(struct inode *inode, const char *full_path,
 		.fid = &fid,
 	};
 
-	cifs_dbg(FYI, "calling SetFileInfo since SetPathInfo for times not supported by this server\n");
-	rc = CIFS_open(xid, &oparms, &oplock, NULL);
+	if (S_ISDIR(inode->i_mode) && !(tcon->ses->capabilities & CAP_NT_SMBS)) {
+		/* Opening directory path is not possible on non-NT servers. */
+		rc = -EOPNOTSUPP;
+	} else {
+		/*
+		 * Use cifs_open_file() instead of CIFS_open() as the
+		 * cifs_open_file() selects the correct function which
+		 * works also on non-NT servers.
+		 */
+		rc = cifs_open_file(xid, &oparms, &oplock, NULL);
+		/*
+		 * Opening path for writing on non-NT servers is not
+		 * possible when the read-only attribute is already set.
+		 * Non-NT server in this case returns -EACCES. For those
+		 * servers the only possible way how to clear the read-only
+		 * bit is via SMB_COM_SETATTR command.
+		 */
+		if (rc == -EACCES &&
+		    (le32_to_cpu(cinode->cifsAttrs) & ATTR_READONLY) &&
+		     le32_to_cpu(buf->Attributes) != 0 && /* 0 = do not change attrs */
+		     !(le32_to_cpu(buf->Attributes) & ATTR_READONLY) &&
+		     !(tcon->ses->capabilities & CAP_NT_SMBS))
+			rc = -EOPNOTSUPP;
+	}
+
+	/* Fallback to SMB_COM_SETATTR command when absolutelty needed. */
+	if (rc == -EOPNOTSUPP) {
+		cifs_dbg(FYI, "calling SetInformation since SetPathInfo for attrs/times not supported by this server\n");
+		rc = SMBSetInformation(xid, tcon, full_path,
+				       buf->Attributes != 0 ? buf->Attributes : cinode->cifsAttrs,
+				       write_time,
+				       cifs_sb->local_nls, cifs_sb);
+		if (rc == 0)
+			cinode->cifsAttrs = le32_to_cpu(buf->Attributes);
+		else
+			rc = -EACCES;
+		goto out;
+	}
+
 	if (rc != 0) {
 		if (rc == -EIO)
 			rc = -EINVAL;
@@ -930,6 +1008,7 @@ smb_set_file_info(struct inode *inode, const char *full_path,
 	}
 
 	netpid = current->tgid;
+	cifs_dbg(FYI, "calling SetFileInfo since SetPathInfo for attrs/times not supported by this server\n");
 
 set_via_filehandle:
 	rc = CIFSSMBSetFileInfo(xid, tcon, buf, fid.netfid, netpid);
@@ -940,6 +1019,21 @@ smb_set_file_info(struct inode *inode, const char *full_path,
 		CIFSSMBClose(xid, tcon, fid.netfid);
 	else
 		cifsFileInfo_put(open_file);
+
+	/*
+	 * Setting the read-only bit is not honered on non-NT servers when done
+	 * via open-semantics. So for setting it, use SMB_COM_SETATTR command.
+	 * This command works only after the file is closed, so use it only when
+	 * operation was called without the filehandle.
+	 */
+	if (open_file == NULL &&
+	    !(tcon->ses->capabilities & CAP_NT_SMBS) &&
+	    le32_to_cpu(buf->Attributes) & ATTR_READONLY) {
+		SMBSetInformation(xid, tcon, full_path,
+				  buf->Attributes,
+				  0 /* do not change write time */,
+				  cifs_sb->local_nls, cifs_sb);
+	}
 out:
 	if (tlink != NULL)
 		cifs_put_tlink(tlink);
-- 
2.20.1

[PATCH 11/12] cifs: Add fallback code path for cifs_mkdir_setinfo()

[Pali Rohár]

Use SMBSetInformation() as a fallback function (when CIFSSMBSetPathInfo()
fails) which can set attribudes on the directory, including changing
read-only attribute.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/smb1ops.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c
index 33af1a6ab348..1697c1fc13b0 100644
--- a/fs/smb/client/smb1ops.c
+++ b/fs/smb/client/smb1ops.c
@@ -800,6 +800,11 @@ cifs_mkdir_setinfo(struct inode *inode, const char *full_path,
 	info.Attributes = cpu_to_le32(dosattrs);
 	rc = CIFSSMBSetPathInfo(xid, tcon, full_path, &info, cifs_sb->local_nls,
 				cifs_sb);
+	if (rc == -EOPNOTSUPP || rc == -EINVAL)
+		rc = SMBSetInformation(xid, tcon, full_path,
+				       info.Attributes,
+				       0 /* do not change write time */,
+				       cifs_sb->local_nls, cifs_sb);
 	if (rc == 0)
 		cifsInode->cifsAttrs = dosattrs;
 }
-- 
2.20.1

[PATCH 12/12] cifs: Remove CIFSSMBSetPathInfoFB() fallback function

[Pali Rohár]

This fallback function CIFSSMBSetPathInfoFB() is called only from
CIFSSMBSetPathInfo() function. CIFSSMBSetPathInfo() is used in
smb_set_file_info() which contains all required fallback code, including
fallback via filehandle.

So the CIFSSMBSetPathInfoFB() is just code duplication, which is not needed
anymore. Therefore remove it.

This change depends on other changes which are extending
cifs_mkdir_setinfo() and smb_set_file_info() functions.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/cifssmb.c | 36 ------------------------------------
 1 file changed, 36 deletions(-)

diff --git a/fs/smb/client/cifssmb.c b/fs/smb/client/cifssmb.c
index acbdb6d92306..9dc946138f18 100644
--- a/fs/smb/client/cifssmb.c
+++ b/fs/smb/client/cifssmb.c
@@ -5478,38 +5478,6 @@ CIFSSMBSetFileDisposition(const unsigned int xid, struct cifs_tcon *tcon,
 	return rc;
 }
 
-static int
-CIFSSMBSetPathInfoFB(const unsigned int xid, struct cifs_tcon *tcon,
-		     const char *fileName, const FILE_BASIC_INFO *data,
-		     const struct nls_table *nls_codepage,
-		     struct cifs_sb_info *cifs_sb)
-{
-	int oplock = 0;
-	struct cifs_open_parms oparms;
-	struct cifs_fid fid;
-	int rc;
-
-	oparms = (struct cifs_open_parms) {
-		.tcon = tcon,
-		.cifs_sb = cifs_sb,
-		.desired_access = GENERIC_WRITE,
-		.create_options = cifs_create_options(cifs_sb, 0),
-		.disposition = FILE_OPEN,
-		.path = fileName,
-		.fid = &fid,
-	};
-
-	rc = CIFS_open(xid, &oparms, &oplock, NULL);
-	if (rc)
-		goto out;
-
-	rc = CIFSSMBSetFileInfo(xid, tcon, data, fid.netfid, current->tgid);
-	CIFSSMBClose(xid, tcon, fid.netfid);
-out:
-
-	return rc;
-}
-
 int
 CIFSSMBSetPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 		   const char *fileName, const FILE_BASIC_INFO *data,
@@ -5586,10 +5554,6 @@ CIFSSMBSetPathInfo(const unsigned int xid, struct cifs_tcon *tcon,
 	if (rc == -EAGAIN)
 		goto SetTimesRetry;
 
-	if (rc == -EOPNOTSUPP)
-		return CIFSSMBSetPathInfoFB(xid, tcon, fileName, data,
-					    nls_codepage, cifs_sb);
-
 	return rc;
 }
 
-- 
2.20.1

[PATCH v2] cifs: Fix and improve cifs_query_path_info() and cifs_query_file_info()

[Pali Rohár]

When CAP_NT_SMBS was not negotiated then do not issue CIFSSMBQPathInfo()
and CIFSSMBQFileInfo() commands. CIFSSMBQPathInfo() is not supported by
non-NT Win9x SMB server and CIFSSMBQFileInfo() returns from Win9x SMB
server bogus data in Attributes field (for example lot of files are marked
as reparse points, even Win9x does not support them and read-only bit is
not marked for read-only files). Correct information is returned by
CIFSFindFirst() or SMBQueryInformation() command.

So as a fallback in cifs_query_path_info() function use CIFSFindFirst()
with SMB_FIND_FILE_FULL_DIRECTORY_INFO level which is supported by both NT
and non-NT servers and as a last option use SMBQueryInformation() as it was
before.

And in function cifs_query_file_info() immediately returns -EOPNOTSUPP when
not communicating with NT server. Client then revalidate inode entry by the
cifs_query_path_info() call, which is working fine. So fstat() syscall on
already opened file will receive correct information.

Note that both fallback functions in non-UNICODE mode expands wildcards.
Therefore those fallback functions cannot be used on paths which contain
SMB wildcard characters (* ? " > <).

CIFSFindFirst() returns all 4 time attributes as opposite of
SMBQueryInformation() which returns only one.

With this change it is possible to query all 4 times attributes from Win9x
server and at the same time, client minimize sending of unsupported
commands to server.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
Changes in v2:
* Handle both possible SMB_FIND_FILE_INFO_STANDARD and
  SMB_FIND_FILE_FULL_DIRECTORY_INFO levels (based on cap_nt_find)
* Fix non_unicode_wildcard, required for follow up v2 change:
  cifs: Improve SMB1 stat() to work also for paths in DELETE_PENDING state
---
 fs/smb/client/smb1ops.c | 103 ++++++++++++++++++++++++++++++++++++----
 1 file changed, 95 insertions(+), 8 deletions(-)

diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c
index ff0a9d0492f5..fef9d08d7bda 100644
--- a/fs/smb/client/smb1ops.c
+++ b/fs/smb/client/smb1ops.c
@@ -550,24 +550,104 @@ static int cifs_query_path_info(const unsigned int xid,
 				const char *full_path,
 				struct cifs_open_info_data *data)
 {
-	int rc;
+	int rc = -EOPNOTSUPP;
 	FILE_ALL_INFO fi = {};
+	struct cifs_search_info search_info = {};
+	bool non_unicode_wildcard = false;
 
 	data->reparse_point = false;
 	data->adjust_tz = false;
 
-	/* could do find first instead but this returns more info */
-	rc = CIFSSMBQPathInfo(xid, tcon, full_path, &fi, 0 /* not legacy */, cifs_sb->local_nls,
-			      cifs_remap(cifs_sb));
 	/*
-	 * BB optimize code so we do not make the above call when server claims
-	 * no NT SMB support and the above call failed at least once - set flag
-	 * in tcon or mount.
+	 * First try CIFSSMBQPathInfo() function which returns more info
+	 * (NumberOfLinks) than CIFSFindFirst() fallback function.
+	 * Some servers like Win9x do not support SMB_QUERY_FILE_ALL_INFO over
+	 * TRANS2_QUERY_PATH_INFORMATION, but supports it with filehandle over
+	 * TRANS2_QUERY_FILE_INFORMATION (function CIFSSMBQFileInfo(). But SMB
+	 * Open command on non-NT servers works only for files, does not work
+	 * for directories. And moreover Win9x SMB server returns bogus data in
+	 * SMB_QUERY_FILE_ALL_INFO Attributes field. So for non-NT servers,
+	 * do not even use CIFSSMBQPathInfo() or CIFSSMBQFileInfo() function.
 	 */
-	if ((rc == -EOPNOTSUPP) || (rc == -EINVAL)) {
+	if (tcon->ses->capabilities & CAP_NT_SMBS)
+		rc = CIFSSMBQPathInfo(xid, tcon, full_path, &fi, 0 /* not legacy */,
+				      cifs_sb->local_nls, cifs_remap(cifs_sb));
+
+	/*
+	 * Non-UNICODE variant of fallback functions below expands wildcards,
+	 * so they cannot be used for querying paths with wildcard characters.
+	 */
+	if (rc && !(tcon->ses->capabilities & CAP_UNICODE) && strpbrk(full_path, "*?\"><"))
+		non_unicode_wildcard = true;
+
+	/*
+	 * Then fallback to CIFSFindFirst() which works also with non-NT servers
+	 * but does not does not provide NumberOfLinks.
+	 */
+	if ((rc == -EOPNOTSUPP || rc == -EINVAL) &&
+	    !non_unicode_wildcard) {
+		if (!(tcon->ses->capabilities & tcon->ses->server->vals->cap_nt_find))
+			search_info.info_level = SMB_FIND_FILE_INFO_STANDARD;
+		else
+			search_info.info_level = SMB_FIND_FILE_FULL_DIRECTORY_INFO;
+		rc = CIFSFindFirst(xid, tcon, full_path, cifs_sb, NULL,
+				   CIFS_SEARCH_CLOSE_ALWAYS | CIFS_SEARCH_CLOSE_AT_END,
+				   &search_info, false);
+		if (rc == 0) {
+			if (!(tcon->ses->capabilities & tcon->ses->server->vals->cap_nt_find)) {
+				FIND_FILE_STANDARD_INFO *di;
+				int offset = tcon->ses->server->timeAdj;
+
+				di = (FIND_FILE_STANDARD_INFO *)search_info.srch_entries_start;
+				fi.CreationTime = cpu_to_le64(cifs_UnixTimeToNT(cnvrtDosUnixTm(
+						di->CreationDate, di->CreationTime, offset)));
+				fi.LastAccessTime = cpu_to_le64(cifs_UnixTimeToNT(cnvrtDosUnixTm(
+						di->LastAccessDate, di->LastAccessTime, offset)));
+				fi.LastWriteTime = cpu_to_le64(cifs_UnixTimeToNT(cnvrtDosUnixTm(
+						di->LastWriteDate, di->LastWriteTime, offset)));
+				fi.ChangeTime = fi.LastWriteTime;
+				fi.Attributes = cpu_to_le32(le16_to_cpu(di->Attributes));
+				fi.AllocationSize = cpu_to_le64(le32_to_cpu(di->AllocationSize));
+				fi.EndOfFile = cpu_to_le64(le32_to_cpu(di->DataSize));
+			} else {
+				FILE_FULL_DIRECTORY_INFO *di;
+
+				di = (FILE_FULL_DIRECTORY_INFO *)search_info.srch_entries_start;
+				fi.CreationTime = di->CreationTime;
+				fi.LastAccessTime = di->LastAccessTime;
+				fi.LastWriteTime = di->LastWriteTime;
+				fi.ChangeTime = di->ChangeTime;
+				fi.Attributes = di->ExtFileAttributes;
+				fi.AllocationSize = di->AllocationSize;
+				fi.EndOfFile = di->EndOfFile;
+				fi.EASize = di->EaSize;
+			}
+			fi.NumberOfLinks = cpu_to_le32(1);
+			fi.DeletePending = 0;
+			fi.Directory = !!(le32_to_cpu(fi.Attributes) & ATTR_DIRECTORY);
+			cifs_buf_release(search_info.ntwrk_buf_start);
+		} else if (!full_path[0]) {
+			/*
+			 * CIFSFindFirst() does not work on root path if the
+			 * root path was exported on the server from the top
+			 * level path (drive letter).
+			 */
+			rc = -EOPNOTSUPP;
+		}
+	}
+
+	/*
+	 * If everything failed then fallback to the legacy SMB command
+	 * SMB_COM_QUERY_INFORMATION which works with all servers, but
+	 * provide just few information.
+	 */
+	if ((rc == -EOPNOTSUPP || rc == -EINVAL) && !non_unicode_wildcard) {
 		rc = SMBQueryInformation(xid, tcon, full_path, &fi, cifs_sb->local_nls,
 					 cifs_remap(cifs_sb));
 		data->adjust_tz = true;
+	} else if ((rc == -EOPNOTSUPP || rc == -EINVAL) && non_unicode_wildcard) {
+		/* Path with non-UNICODE wildcard character cannot exist. */
+		rc = -ENOENT;
 	}
 
 	if (!rc) {
@@ -646,6 +726,13 @@ static int cifs_query_file_info(const unsigned int xid, struct cifs_tcon *tcon,
 	int rc;
 	FILE_ALL_INFO fi = {};
 
+	/*
+	 * CIFSSMBQFileInfo() for non-NT servers returns bogus data in
+	 * Attributes fields. So do not use this command for non-NT servers.
+	 */
+	if (!(tcon->ses->capabilities & CAP_NT_SMBS))
+		return -EOPNOTSUPP;
+
 	if (cfile->symlink_target) {
 		data->symlink_target = kstrdup(cfile->symlink_target, GFP_KERNEL);
 		if (!data->symlink_target)
-- 
2.20.1

[PATCH v2] cifs: Improve SMB1 stat() to work also for paths in DELETE_PENDING state

[Pali Rohár]

Windows NT SMB server may return -EBUSY (STATUS_DELETE_PENDING) from
CIFSSMBQPathInfo() function for files which are in DELETE_PENDING state.
When this happens, it is still possible to use CIFSFindFirst() fallback.
So allow to use CIFSFindFirst() fallback also for -EBUSY error.

This change fixes stat() to work also against Windows Server 2022 for files
in DELETE_PENDING state.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
Changes in v2:
* Extend comment
* Update on top of the v2 change:
  cifs: Fix and improve cifs_query_path_info() and cifs_query_file_info()
---
 fs/smb/client/smb1ops.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/smb/client/smb1ops.c b/fs/smb/client/smb1ops.c
index fef9d08d7bda..9805dd6fb1d0 100644
--- a/fs/smb/client/smb1ops.c
+++ b/fs/smb/client/smb1ops.c
@@ -582,9 +582,10 @@ static int cifs_query_path_info(const unsigned int xid,
 
 	/*
 	 * Then fallback to CIFSFindFirst() which works also with non-NT servers
-	 * but does not does not provide NumberOfLinks.
+	 * but does not does not provide NumberOfLinks. Also it works for files
+	 * in DELETE_PENDING state (CIFSSMBQPathInfo() returns -EBUSY for them).
 	 */
-	if ((rc == -EOPNOTSUPP || rc == -EINVAL) &&
+	if ((rc == -EOPNOTSUPP || rc == -EINVAL || rc == -EBUSY) &&
 	    !non_unicode_wildcard) {
 		if (!(tcon->ses->capabilities & tcon->ses->server->vals->cap_nt_find))
 			search_info.info_level = SMB_FIND_FILE_INFO_STANDARD;
-- 
2.20.1