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* [PATCH 1/5] cifs: Fix access_flags_to_smbopen_mode
@ 2024-12-31 22:35 Pali Rohár
  2024-12-31 22:35 ` [PATCH 2/5] cifs: Do not add FILE_READ_ATTRIBUTES when using GENERIC_READ/EXECUTE/ALL Pali Rohár
                   ` (3 more replies)
  0 siblings, 4 replies; 5+ messages in thread
From: Pali Rohár @ 2024-12-31 22:35 UTC (permalink / raw)
  To: Steve French, Paulo Alcantara; +Cc: linux-cifs, linux-kernel

When converting access_flags to SMBOPEN mode, check for all possible access
flags, not only GENERIC_READ and GENERIC_WRITE flags.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/cifssmb.c | 32 ++++++++++++++++++++++++--------
 1 file changed, 24 insertions(+), 8 deletions(-)

diff --git a/fs/smb/client/cifssmb.c b/fs/smb/client/cifssmb.c
index dd71c4c8f776..604e204e3f57 100644
--- a/fs/smb/client/cifssmb.c
+++ b/fs/smb/client/cifssmb.c
@@ -1024,15 +1024,31 @@ static __u16 convert_disposition(int disposition)
 static int
 access_flags_to_smbopen_mode(const int access_flags)
 {
-	int masked_flags = access_flags & (GENERIC_READ | GENERIC_WRITE);
-
-	if (masked_flags == GENERIC_READ)
-		return SMBOPEN_READ;
-	else if (masked_flags == GENERIC_WRITE)
+	/*
+	 * SYSTEM_SECURITY grants both read and write access to SACL, treat is as read/write.
+	 * MAXIMUM_ALLOWED grants as many access as possible, so treat it as read/write too.
+	 * SYNCHRONIZE as is does not grant any specific access, so do not check its mask.
+	 * If only SYNCHRONIZE bit is specified then fallback to read access.
+	 */
+	bool with_write_flags = access_flags & (FILE_WRITE_DATA | FILE_APPEND_DATA | FILE_WRITE_EA |
+						FILE_DELETE_CHILD | FILE_WRITE_ATTRIBUTES | DELETE |
+						WRITE_DAC | WRITE_OWNER | SYSTEM_SECURITY |
+						MAXIMUM_ALLOWED | GENERIC_WRITE | GENERIC_ALL);
+	bool with_read_flags = access_flags & (FILE_READ_DATA | FILE_READ_EA | FILE_EXECUTE |
+						FILE_READ_ATTRIBUTES | READ_CONTROL |
+						SYSTEM_SECURITY | MAXIMUM_ALLOWED | GENERIC_ALL |
+						GENERIC_EXECUTE | GENERIC_READ);
+	bool with_execute_flags = access_flags & (FILE_EXECUTE | MAXIMUM_ALLOWED | GENERIC_ALL |
+						GENERIC_EXECUTE);
+
+	if (with_write_flags && with_read_flags)
+		return SMBOPEN_READWRITE;
+	else if (with_write_flags)
 		return SMBOPEN_WRITE;
-
-	/* just go for read/write */
-	return SMBOPEN_READWRITE;
+	else if (with_execute_flags)
+		return SMBOPEN_EXECUTE;
+	else
+		return SMBOPEN_READ;
 }
 
 int
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 2/5] cifs: Do not add FILE_READ_ATTRIBUTES when using GENERIC_READ/EXECUTE/ALL
  2024-12-31 22:35 [PATCH 1/5] cifs: Fix access_flags_to_smbopen_mode Pali Rohár
@ 2024-12-31 22:35 ` Pali Rohár
  2024-12-31 22:35 ` [PATCH 3/5] cifs: Improve SMB2+ stat() to work also on non-present name surrogate reparse points Pali Rohár
                   ` (2 subsequent siblings)
  3 siblings, 0 replies; 5+ messages in thread
From: Pali Rohár @ 2024-12-31 22:35 UTC (permalink / raw)
  To: Steve French, Paulo Alcantara; +Cc: linux-cifs, linux-kernel

Individual bits GENERIC_READ, GENERIC_EXECUTE and GENERIC_ALL have meaning
which includes also access right for FILE_READ_ATTRIBUTES. So specifying
FILE_READ_ATTRIBUTES bit together with one of those GENERIC (except
GENERIC_WRITE) does not do anything.

This change prevents calling additional (fallback) code and sending more
requests without FILE_READ_ATTRIBUTES when the primary request fails on
-EACCES, as it is not needed at all.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/smb2file.c | 9 +++++++++
 1 file changed, 9 insertions(+)

diff --git a/fs/smb/client/smb2file.c b/fs/smb/client/smb2file.c
index 1476cb824ae4..0f3d20b597d6 100644
--- a/fs/smb/client/smb2file.c
+++ b/fs/smb/client/smb2file.c
@@ -158,7 +158,16 @@ int smb2_open_file(const unsigned int xid, struct cifs_open_parms *oparms, __u32
 	if (smb2_path == NULL)
 		return -ENOMEM;
 
+	/*
+	 * GENERIC_READ, GENERIC_EXECUTE, GENERIC_ALL and MAXIMUM_ALLOWED
+	 * contains also FILE_READ_ATTRIBUTES access right. So do not append
+	 * FILE_READ_ATTRIBUTES when not needed and prevent calling code path
+	 * for retry_without_read_attributes.
+	 */
 	if (!(oparms->desired_access & FILE_READ_ATTRIBUTES) &&
+	    !(oparms->desired_access & GENERIC_READ) &&
+	    !(oparms->desired_access & GENERIC_EXECUTE) &&
+	    !(oparms->desired_access & GENERIC_ALL) &&
 	    !(oparms->desired_access & MAXIMUM_ALLOWED)) {
 		oparms->desired_access |= FILE_READ_ATTRIBUTES;
 		retry_without_read_attributes = true;
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 3/5] cifs: Improve SMB2+ stat() to work also on non-present name surrogate reparse points
  2024-12-31 22:35 [PATCH 1/5] cifs: Fix access_flags_to_smbopen_mode Pali Rohár
  2024-12-31 22:35 ` [PATCH 2/5] cifs: Do not add FILE_READ_ATTRIBUTES when using GENERIC_READ/EXECUTE/ALL Pali Rohár
@ 2024-12-31 22:35 ` Pali Rohár
  2024-12-31 22:35 ` [PATCH 4/5] cifs: Improve SMB2+ stat() to work also for paths in DELETE_PENDING state Pali Rohár
  2024-12-31 22:35 ` [PATCH 5/5] cifs: Improve detect_directory_symlink_target() function Pali Rohár
  3 siblings, 0 replies; 5+ messages in thread
From: Pali Rohár @ 2024-12-31 22:35 UTC (permalink / raw)
  To: Steve French, Paulo Alcantara; +Cc: linux-cifs, linux-kernel

SMB server returns STATUS_OBJECT_PATH_NOT_FOUND if the path exists, is the
reparse point of name surrogate type (e.g. mount point) and surrogate
target location does not exist.

So if the server returns STATUS_OBJECT_PATH_NOT_FOUND error then it is
required to send request again with OPEN_REPARSE_POINT flag. This is needed
to distinguish between path does not exist and path exists and points to
non-existent surrogate location.

Before this change, Linux SMB client returned for non-present name
surrogate reparse point -ENOENT error. With this change it correctly
returns that the entry exits, it is of directory type with filled stat
information.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/smb2inode.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/fs/smb/client/smb2inode.c b/fs/smb/client/smb2inode.c
index 0b8d6d8f724d..b6342b043073 100644
--- a/fs/smb/client/smb2inode.c
+++ b/fs/smb/client/smb2inode.c
@@ -958,6 +958,18 @@ int smb2_query_path_info(const unsigned int xid,
 	if (!hdr || out_buftype[0] == CIFS_NO_BUFFER)
 		goto out;
 
+	/*
+	 * SMB server returns STATUS_OBJECT_PATH_NOT_FOUND if the path exists,
+	 * is the reparse point of name surrogate type (e.g. mount point) and
+	 * surrogate target location does not exist.
+	 * So if the server returns STATUS_OBJECT_PATH_NOT_FOUND error then it
+	 * is required to send request again with OPEN_REPARSE_POINT flag.
+	 * Re-opening with OPEN_REPARSE_POINT is done in the case when rc is
+	 * -EOPNOTSUPP.
+	 */
+	if (hdr->Status == STATUS_OBJECT_PATH_NOT_FOUND)
+		rc = -EOPNOTSUPP;
+
 	switch (rc) {
 	case 0:
 		rc = parse_create_response(data, cifs_sb, full_path, &out_iov[0]);
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 4/5] cifs: Improve SMB2+ stat() to work also for paths in DELETE_PENDING state
  2024-12-31 22:35 [PATCH 1/5] cifs: Fix access_flags_to_smbopen_mode Pali Rohár
  2024-12-31 22:35 ` [PATCH 2/5] cifs: Do not add FILE_READ_ATTRIBUTES when using GENERIC_READ/EXECUTE/ALL Pali Rohár
  2024-12-31 22:35 ` [PATCH 3/5] cifs: Improve SMB2+ stat() to work also on non-present name surrogate reparse points Pali Rohár
@ 2024-12-31 22:35 ` Pali Rohár
  2024-12-31 22:35 ` [PATCH 5/5] cifs: Improve detect_directory_symlink_target() function Pali Rohár
  3 siblings, 0 replies; 5+ messages in thread
From: Pali Rohár @ 2024-12-31 22:35 UTC (permalink / raw)
  To: Steve French, Paulo Alcantara; +Cc: linux-cifs, linux-kernel

Paths in DELETE_PENDING state cannot be opened at all. So standard way of
querying path attributes for this case is not possible.

There is an alternative way how to query limited information about file
over SMB2+ dialects without opening file itself. It is by opening the
parent directory, querying specific child with filled search filer and
asking for attributes for that child.

Implement this fallback when standard case in smb2_query_path_info fails
with STATUS_DELETE_PENDING error and stat was asked for path which is not
top level one (because top level does not have parent directory at all).

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/cifsglob.h  |   1 +
 fs/smb/client/smb2glob.h  |   1 +
 fs/smb/client/smb2inode.c | 171 +++++++++++++++++++++++++++++++++++++-
 3 files changed, 170 insertions(+), 3 deletions(-)

diff --git a/fs/smb/client/cifsglob.h b/fs/smb/client/cifsglob.h
index 06ad727e824b..1338b3473ef3 100644
--- a/fs/smb/client/cifsglob.h
+++ b/fs/smb/client/cifsglob.h
@@ -2329,6 +2329,7 @@ struct smb2_compound_vars {
 	struct smb_rqst rqst[MAX_COMPOUND];
 	struct kvec open_iov[SMB2_CREATE_IOV_SIZE];
 	struct kvec qi_iov;
+	struct kvec qd_iov[SMB2_QUERY_DIRECTORY_IOV_SIZE];
 	struct kvec io_iov[SMB2_IOCTL_IOV_SIZE];
 	struct kvec si_iov[SMB2_SET_INFO_IOV_SIZE];
 	struct kvec close_iov;
diff --git a/fs/smb/client/smb2glob.h b/fs/smb/client/smb2glob.h
index 224495322a05..1cb219605e75 100644
--- a/fs/smb/client/smb2glob.h
+++ b/fs/smb/client/smb2glob.h
@@ -39,6 +39,7 @@ enum smb2_compound_ops {
 	SMB2_OP_GET_REPARSE,
 	SMB2_OP_QUERY_WSL_EA,
 	SMB2_OP_OPEN_QUERY,
+	SMB2_OP_QUERY_DIRECTORY,
 };
 
 /* Used when constructing chained read requests. */
diff --git a/fs/smb/client/smb2inode.c b/fs/smb/client/smb2inode.c
index b6342b043073..1a8a2f83a3d9 100644
--- a/fs/smb/client/smb2inode.c
+++ b/fs/smb/client/smb2inode.c
@@ -190,6 +190,8 @@ static int smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon,
 	int resp_buftype[MAX_COMPOUND];
 	struct smb2_create_rsp *create_rsp = NULL;
 	struct smb2_query_info_rsp *qi_rsp = NULL;
+	struct smb2_query_directory_req *qd_rqst = NULL;
+	struct smb2_query_directory_rsp *qd_rsp = NULL;
 	struct cifs_open_info_data *idata;
 	struct inode *inode = NULL;
 	int flags = 0;
@@ -344,6 +346,39 @@ static int smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon,
 			trace_smb3_posix_query_info_compound_enter(xid, ses->Suid,
 								   tcon->tid, full_path);
 			break;
+		case SMB2_OP_QUERY_DIRECTORY:
+			rqst[num_rqst].rq_iov = &vars->qd_iov[0];
+			rqst[num_rqst].rq_nvec = SMB2_QUERY_DIRECTORY_IOV_SIZE;
+
+			rc = SMB2_query_directory_init(xid,
+						       tcon,
+						       server,
+						       &rqst[num_rqst],
+						       cfile ? cfile->fid.persistent_fid : COMPOUND_FID,
+						       cfile ? cfile->fid.volatile_fid : COMPOUND_FID,
+						       0,
+						       (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) ?
+						        SMB_FIND_FILE_ID_FULL_DIR_INFO :
+						        SMB_FIND_FILE_FULL_DIRECTORY_INFO);
+			if (!rc) {
+				/*
+				 * Change the default search wildcard pattern '*'
+				 * to the requested file name stored in in_iov[i]
+				 * and request for only one single entry.
+				 */
+				qd_rqst = rqst[num_rqst].rq_iov[0].iov_base;
+				qd_rqst->Flags |= SMB2_RETURN_SINGLE_ENTRY;
+				qd_rqst->FileNameLength = cpu_to_le16(in_iov[i].iov_len);
+				rqst[num_rqst].rq_iov[1] = in_iov[i];
+			}
+			if (!rc && (!cfile || num_rqst > 1)) {
+				smb2_set_next_command(tcon, &rqst[num_rqst]);
+				smb2_set_related(&rqst[num_rqst]);
+			} else if (rc) {
+				goto finished;
+			}
+			num_rqst++;
+			break;
 		case SMB2_OP_DELETE:
 			trace_smb3_delete_enter(xid, ses->Suid, tcon->tid, full_path);
 			break;
@@ -716,6 +751,55 @@ static int smb2_compound_op(const unsigned int xid, struct cifs_tcon *tcon,
 				trace_smb3_posix_query_info_compound_done(xid, ses->Suid,
 									  tcon->tid);
 			break;
+		case SMB2_OP_QUERY_DIRECTORY:
+			if (rc == 0) {
+				qd_rsp = (struct smb2_query_directory_rsp *)
+					rsp_iov[i + 1].iov_base;
+				rc = smb2_validate_iov(le16_to_cpu(qd_rsp->OutputBufferOffset),
+						       le32_to_cpu(qd_rsp->OutputBufferLength),
+						       &rsp_iov[i + 1],
+						       (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM) ?
+						        sizeof(SEARCH_ID_FULL_DIR_INFO) :
+						        sizeof(FILE_FULL_DIRECTORY_INFO));
+			}
+			if (rc == 0) {
+				/*
+				 * Both SEARCH_ID_FULL_DIR_INFO and FILE_FULL_DIRECTORY_INFO
+				 * have same member offsets except the UniqueId and FileName.
+				 */
+				SEARCH_ID_FULL_DIR_INFO *si = (SEARCH_ID_FULL_DIR_INFO *)qd_rsp->Buffer;
+				idata = in_iov[i + 1].iov_base;
+				idata->fi.CreationTime = si->CreationTime;
+				idata->fi.LastAccessTime = si->LastAccessTime;
+				idata->fi.LastWriteTime = si->LastWriteTime;
+				idata->fi.ChangeTime = si->ChangeTime;
+				idata->fi.Attributes = si->ExtFileAttributes;
+				idata->fi.AllocationSize = si->AllocationSize;
+				idata->fi.EndOfFile = si->EndOfFile;
+				idata->fi.EASize = si->EaSize;
+				/*
+				 * UniqueId is present only in struct SEARCH_ID_FULL_DIR_INFO.
+				 * It is not present in struct FILE_FULL_DIRECTORY_INFO.
+				 * struct SEARCH_ID_FULL_DIR_INFO was requested only when
+				 * CIFS_MOUNT_SERVER_INUM is set.
+				 */
+				if (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)
+					idata->fi.IndexNumber = si->UniqueId;
+				if (le32_to_cpu(idata->fi.NumberOfLinks) == 0)
+					idata->fi.NumberOfLinks = cpu_to_le32(1); /* dummy value */
+				idata->fi.DeletePending = 0;
+				idata->fi.Directory = !!(le32_to_cpu(si->ExtFileAttributes) & ATTR_DIRECTORY);
+			}
+			SMB2_query_directory_free(&rqst[num_rqst++]);
+			if (rc)
+				trace_smb3_query_dir_err(xid,
+							 cfile ? cfile->fid.persistent_fid : COMPOUND_FID,
+							 tcon->tid, ses->Suid, 0, 0, rc);
+			else
+				trace_smb3_query_dir_done(xid,
+							  cfile ? cfile->fid.persistent_fid : COMPOUND_FID,
+							  tcon->tid, ses->Suid, 0, 0);
+			break;
 		case SMB2_OP_DELETE:
 			if (rc)
 				trace_smb3_delete_err(xid,  ses->Suid, tcon->tid, rc);
@@ -894,6 +978,7 @@ int smb2_query_path_info(const unsigned int xid,
 	struct cifs_open_parms oparms;
 	__u32 create_options = 0;
 	struct cifsFileInfo *cfile;
+	struct cifsFileInfo *parent_cfile;
 	struct cached_fid *cfid = NULL;
 	struct smb2_hdr *hdr;
 	struct kvec in_iov[3], out_iov[3] = {};
@@ -1085,9 +1170,9 @@ int smb2_query_path_info(const unsigned int xid,
 		break;
 	case -EREMOTE:
 		break;
-	default:
-		if (hdr->Status != STATUS_OBJECT_NAME_INVALID)
-			break;
+	}
+
+	if (hdr->Status == STATUS_OBJECT_NAME_INVALID) {
 		rc2 = cifs_inval_name_dfs_link_error(xid, tcon, cifs_sb,
 						     full_path, &islink);
 		if (rc2) {
@@ -1096,6 +1181,86 @@ int smb2_query_path_info(const unsigned int xid,
 		}
 		if (islink)
 			rc = -EREMOTE;
+	} else if (hdr->Status == STATUS_DELETE_PENDING && full_path[0]) {
+		/*
+		 * If SMB2 OPEN/CREATE fails with STATUS_DELETE_PENDING error,
+		 * it means that the path is in delete pending state and it is
+		 * not possible to open it until some other client clears delete
+		 * pending state or all other clients close all opened handles
+		 * to that path.
+		 *
+		 * There is an alternative way how to query limited information
+		 * about path which is in delete pending state still suitable
+		 * for the stat() syscall. It is by opening the parent directory,
+		 * querying specific child with filled search filer and asking
+		 * for attributes for that child.
+		 */
+
+		char *parent_path;
+		const char *basename;
+		__le16 *basename_utf16;
+		int basename_utf16_len;
+
+		basename = strrchr(full_path, CIFS_DIR_SEP(cifs_sb));
+		if (basename) {
+			parent_path = kstrndup(full_path, basename - full_path, GFP_KERNEL);
+			basename++;
+		} else {
+			parent_path = kstrdup("", GFP_KERNEL);
+			basename = full_path;
+		}
+
+		if (!parent_path) {
+			rc = -ENOMEM;
+			goto out;
+		}
+
+		basename_utf16 = cifs_convert_path_to_utf16(basename, cifs_sb);
+		if (!basename_utf16) {
+			kfree(parent_path);
+			rc = -ENOMEM;
+			goto out;
+		}
+
+		basename_utf16_len = 2 * UniStrnlen((wchar_t *)basename_utf16, PATH_MAX);
+
+retry_query_directory:
+		for (i = 0; i < ARRAY_SIZE(out_buftype); i++) {
+			free_rsp_buf(out_buftype[i], out_iov[i].iov_base);
+			out_buftype[i] = 0;
+			out_iov[i].iov_base = NULL;
+		}
+
+		num_cmds = 1;
+		cmds[0] = SMB2_OP_QUERY_DIRECTORY;
+		in_iov[0].iov_base = basename_utf16;
+		in_iov[0].iov_len = basename_utf16_len;
+		in_iov[1].iov_base = data;
+		in_iov[1].iov_len = sizeof(*data);
+		oparms = CIFS_OPARMS(cifs_sb, tcon, parent_path, FILE_READ_DATA,
+				     FILE_OPEN, CREATE_NOT_FILE, ACL_NO_MODE);
+		cifs_get_readable_path(tcon, parent_path, &parent_cfile);
+		rc = smb2_compound_op(xid, tcon, cifs_sb, parent_path,
+				      &oparms, in_iov, cmds, num_cmds,
+				      parent_cfile, out_iov, out_buftype, NULL);
+		if (rc == -EOPNOTSUPP && (cifs_sb->mnt_cifs_flags & CIFS_MOUNT_SERVER_INUM)) {
+			/*
+			 * If querying of server inode numbers is not supported
+			 * but is enabled, then disable it and try again.
+			 */
+			cifs_autodisable_serverino(cifs_sb);
+			goto retry_query_directory;
+		}
+
+		kfree(parent_path);
+		kfree(basename_utf16);
+
+		hdr = out_iov[0].iov_base;
+		if (!hdr || out_buftype[0] == CIFS_NO_BUFFER)
+			goto out;
+
+		/* As we are in code path for STATUS_DELETE_PENDING, set DeletePending. */
+		data->fi.DeletePending = 1;
 	}
 
 out:
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* [PATCH 5/5] cifs: Improve detect_directory_symlink_target() function
  2024-12-31 22:35 [PATCH 1/5] cifs: Fix access_flags_to_smbopen_mode Pali Rohár
                   ` (2 preceding siblings ...)
  2024-12-31 22:35 ` [PATCH 4/5] cifs: Improve SMB2+ stat() to work also for paths in DELETE_PENDING state Pali Rohár
@ 2024-12-31 22:35 ` Pali Rohár
  3 siblings, 0 replies; 5+ messages in thread
From: Pali Rohár @ 2024-12-31 22:35 UTC (permalink / raw)
  To: Steve French, Paulo Alcantara; +Cc: linux-cifs, linux-kernel

Function detect_directory_symlink_target() is not curruntly able to detect
if the target path is directory in case the path is in the DELETE_PENDING
state or the user has not granted FILE_READ_ATTRIBUTES permission on the
path. This limitation is written in TODO comment.

Resolve this problem by replacing code which determinate path type by the
query_path_info() callback, which now is able to handle all these cases.

Signed-off-by: Pali Rohár <pali@kernel.org>
---
 fs/smb/client/reparse.c | 75 ++++++++++++++---------------------------
 1 file changed, 25 insertions(+), 50 deletions(-)

diff --git a/fs/smb/client/reparse.c b/fs/smb/client/reparse.c
index 69efbcae6683..ad53b9b4a238 100644
--- a/fs/smb/client/reparse.c
+++ b/fs/smb/client/reparse.c
@@ -248,18 +248,16 @@ static int detect_directory_symlink_target(struct cifs_sb_info *cifs_sb,
 					   bool *directory)
 {
 	char sep = CIFS_DIR_SEP(cifs_sb);
-	struct cifs_open_parms oparms;
+	struct cifs_open_info_data query_info;
 	struct tcon_link *tlink;
 	struct cifs_tcon *tcon;
 	const char *basename;
-	struct cifs_fid fid;
 	char *resolved_path;
 	int full_path_len;
 	int basename_len;
 	int symname_len;
 	char *path_sep;
-	__u32 oplock;
-	int open_rc;
+	int query_rc;
 
 	/*
 	 * First do some simple check. If the original Linux symlink target ends
@@ -282,7 +280,8 @@ static int detect_directory_symlink_target(struct cifs_sb_info *cifs_sb,
 	if (symname[0] == '/') {
 		cifs_dbg(FYI,
 			 "%s: cannot determinate if the symlink target path '%s' "
-			 "is directory or not, creating '%s' as file symlink\n",
+			 "is directory or not because path is absolute, "
+			 "creating '%s' as file symlink\n",
 			 __func__, symname, full_path);
 		return 0;
 	}
@@ -320,58 +319,34 @@ static int detect_directory_symlink_target(struct cifs_sb_info *cifs_sb,
 	if (sep == '\\')
 		convert_delimiter(path_sep, sep);
 
+	/*
+	 * Query resolved SMB symlink path and check if it is a directory or not.
+	 * Callback query_path_info() already handles cases when the server does
+	 * not grant FILE_READ_ATTRIBUTES permission for object, or when server
+	 * denies opening the object (e.g. because of DELETE_PENDING state).
+	 */
 	tcon = tlink_tcon(tlink);
-	oparms = CIFS_OPARMS(cifs_sb, tcon, resolved_path,
-			     FILE_READ_ATTRIBUTES, FILE_OPEN, 0, ACL_NO_MODE);
-	oparms.fid = &fid;
-
-	/* Try to open as a directory (NOT_FILE) */
-	oplock = 0;
-	oparms.create_options = cifs_create_options(cifs_sb,
-						    CREATE_NOT_FILE | OPEN_REPARSE_POINT);
-	open_rc = tcon->ses->server->ops->open(xid, &oparms, &oplock, NULL);
-	if (open_rc == 0) {
-		/* Successful open means that the target path is definitely a directory. */
-		*directory = true;
-		tcon->ses->server->ops->close(xid, tcon, &fid);
-	} else if (open_rc == -ENOTDIR) {
-		/* -ENOTDIR means that the target path is definitely a file. */
-		*directory = false;
-	} else if (open_rc == -ENOENT) {
+	query_rc = tcon->ses->server->ops->query_path_info(xid, tcon, cifs_sb,
+							   resolved_path, &query_info);
+	if (query_rc == 0) {
+		/* Query on path was successful, so just check for directory attr. */
+		*directory = le32_to_cpu(query_info.fi.Attributes) & ATTR_DIRECTORY;
+	} else if (query_rc == -ENOENT) {
 		/* -ENOENT means that the target path does not exist. */
 		cifs_dbg(FYI,
 			 "%s: symlink target path '%s' does not exist, "
 			 "creating '%s' as file symlink\n",
 			 __func__, symname, full_path);
 	} else {
-		/* Try to open as a file (NOT_DIR) */
-		oplock = 0;
-		oparms.create_options = cifs_create_options(cifs_sb,
-							    CREATE_NOT_DIR | OPEN_REPARSE_POINT);
-		open_rc = tcon->ses->server->ops->open(xid, &oparms, &oplock, NULL);
-		if (open_rc == 0) {
-			/* Successful open means that the target path is definitely a file. */
-			*directory = false;
-			tcon->ses->server->ops->close(xid, tcon, &fid);
-		} else if (open_rc == -EISDIR) {
-			/* -EISDIR means that the target path is definitely a directory. */
-			*directory = true;
-		} else {
-			/*
-			 * This code branch is called when we do not have a permission to
-			 * open the resolved_path or some other client/process denied
-			 * opening the resolved_path.
-			 *
-			 * TODO: Try to use ops->query_dir_first on the parent directory
-			 * of resolved_path, search for basename of resolved_path and
-			 * check if the ATTR_DIRECTORY is set in fi.Attributes. In some
-			 * case this could work also when opening of the path is denied.
-			 */
-			cifs_dbg(FYI,
-				 "%s: cannot determinate if the symlink target path '%s' "
-				 "is directory or not, creating '%s' as file symlink\n",
-				 __func__, symname, full_path);
-		}
+		/*
+		 * This code branch is called when we do not have a permission to
+		 * query the resolved_path or some other error occurred during query.
+		 */
+		cifs_dbg(FYI,
+			 "%s: cannot determinate if the symlink target path '%s' "
+			 "is directory or not because query path failed (%d), "
+			 "creating '%s' as file symlink\n",
+			 __func__, symname, query_rc, full_path);
 	}
 
 	kfree(resolved_path);
-- 
2.20.1


^ permalink raw reply related	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2024-12-31 22:35 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2024-12-31 22:35 [PATCH 1/5] cifs: Fix access_flags_to_smbopen_mode Pali Rohár
2024-12-31 22:35 ` [PATCH 2/5] cifs: Do not add FILE_READ_ATTRIBUTES when using GENERIC_READ/EXECUTE/ALL Pali Rohár
2024-12-31 22:35 ` [PATCH 3/5] cifs: Improve SMB2+ stat() to work also on non-present name surrogate reparse points Pali Rohár
2024-12-31 22:35 ` [PATCH 4/5] cifs: Improve SMB2+ stat() to work also for paths in DELETE_PENDING state Pali Rohár
2024-12-31 22:35 ` [PATCH 5/5] cifs: Improve detect_directory_symlink_target() function Pali Rohár

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