* [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