[PATCH 6.6 060/102] ksmbd: add support for durable handles v1/v2

Greg Kroah-Hartman
2024-05-23T13:25:06Z

From: Namjae Jeon <linkinjeon@kernel.org>

[ Upstream commit c8efcc786146a951091588e5fa7e3c754850cb3c ]

Durable file handles allow reopening a file preserved on a short
network outage and transparent client reconnection within a timeout.
i.e. Durable handles aren't necessarily cleaned up when the opening
process terminates.

This patch add support for durable handle version 1 and 2.

To prove durable handles work on ksmbd, I have tested this patch with
the following smbtorture tests:

smb2.durable-open.open-oplock
smb2.durable-open.open-lease
smb2.durable-open.reopen1
smb2.durable-open.reopen1a
smb2.durable-open.reopen1a-lease
smb2.durable-open.reopen2
smb2.durable-open.reopen2a
smb2.durable-open.reopen2-lease
smb2.durable-open.reopen2-lease-v2
smb2.durable-open.reopen3
smb2.durable-open.reopen4
smb2.durable-open.delete_on_close2
smb2.durable-open.file-position
smb2.durable-open.lease
smb2.durable-open.alloc-size
smb2.durable-open.read-only
smb2.durable-v2-open.create-blob
smb2.durable-v2-open.open-oplock
smb2.durable-v2-open.open-lease
smb2.durable-v2-open.reopen1
smb2.durable-v2-open.reopen1a
smb2.durable-v2-open.reopen1a-lease
smb2.durable-v2-open.reopen2
smb2.durable-v2-open.reopen2b

Signed-off-by: Namjae Jeon <linkinjeon@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
fs/smb/server/ksmbd_netlink.h | 1 +
fs/smb/server/mgmt/user_session.c | 1 +
fs/smb/server/oplock.c | 94 +++++++++--
fs/smb/server/oplock.h | 7 +-
fs/smb/server/smb2ops.c | 6 +
fs/smb/server/smb2pdu.c | 257 +++++++++++++++++++++++++++++-
fs/smb/server/smb2pdu.h | 15 ++
fs/smb/server/vfs_cache.c | 137 +++++++++++++++-
fs/smb/server/vfs_cache.h | 9 ++
9 files changed, 506 insertions(+), 21 deletions(-)

diff --git a/fs/smb/server/ksmbd_netlink.h b/fs/smb/server/ksmbd_netlink.h
index 4464a62228cf3..686b321c5a8bb 100644
--- a/fs/smb/server/ksmbd_netlink.h
+++ b/fs/smb/server/ksmbd_netlink.h
@@ -75,6 +75,7 @@ struct ksmbd_heartbeat {
#define KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION BIT(1)
#define KSMBD_GLOBAL_FLAG_SMB3_MULTICHANNEL BIT(2)
#define KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION_OFF BIT(3)
+#define KSMBD_GLOBAL_FLAG_DURABLE_HANDLE BIT(4)

/*
* IPC request for ksmbd server startup
diff --git a/fs/smb/server/mgmt/user_session.c b/fs/smb/server/mgmt/user_session.c
index 83074672fe812..aec0a7a124052 100644
--- a/fs/smb/server/mgmt/user_session.c
+++ b/fs/smb/server/mgmt/user_session.c
@@ -324,6 +324,7 @@ void destroy_previous_session(struct ksmbd_conn *conn,
memcmp(user->passkey, prev_user->passkey, user->passkey_sz))
goto out;

+ ksmbd_destroy_file_table(&prev_sess->file_table);
prev_sess->state = SMB2_SESSION_EXPIRED;
out:
up_write(&conn->session_lock);
diff --git a/fs/smb/server/oplock.c b/fs/smb/server/oplock.c
index dc729ab980dc0..7bdae2adad228 100644
--- a/fs/smb/server/oplock.c
+++ b/fs/smb/server/oplock.c
@@ -159,7 +159,8 @@ static struct oplock_info *opinfo_get_list(struct ksmbd_inode *ci)
opinfo = list_first_or_null_rcu(&ci->m_op_list, struct oplock_info,
op_entry);
if (opinfo) {
- if (!atomic_inc_not_zero(&opinfo->refcount))
+ if (opinfo->conn == NULL ||
+ !atomic_inc_not_zero(&opinfo->refcount))
opinfo = NULL;
else {
atomic_inc(&opinfo->conn->r_count);
@@ -527,7 +528,7 @@ static struct oplock_info *same_client_has_lease(struct ksmbd_inode *ci,
*/
read_lock(&ci->m_lock);
list_for_each_entry(opinfo, &ci->m_op_list, op_entry) {
- if (!opinfo->is_lease)
+ if (!opinfo->is_lease || !opinfo->conn)
continue;
read_unlock(&ci->m_lock);
lease = opinfo->o_lease;
@@ -651,7 +652,7 @@ static void __smb2_oplock_break_noti(struct work_struct *wk)
struct smb2_hdr *rsp_hdr;
struct ksmbd_file *fp;

- fp = ksmbd_lookup_durable_fd(br_info->fid);
+ fp = ksmbd_lookup_global_fd(br_info->fid);
if (!fp)
goto out;

@@ -1115,7 +1116,7 @@ void smb_send_parent_lease_break_noti(struct ksmbd_file *fp,

read_lock(&p_ci->m_lock);
list_for_each_entry(opinfo, &p_ci->m_op_list, op_entry) {
- if (!opinfo->is_lease)
+ if (opinfo->conn == NULL || !opinfo->is_lease)
continue;

if (opinfo->o_lease->state != SMB2_OPLOCK_LEVEL_NONE &&
@@ -1160,7 +1161,7 @@ void smb_lazy_parent_lease_break_close(struct ksmbd_file *fp)

read_lock(&p_ci->m_lock);
list_for_each_entry(opinfo, &p_ci->m_op_list, op_entry) {
- if (!opinfo->is_lease)
+ if (opinfo->conn == NULL || !opinfo->is_lease)
continue;

if (opinfo->o_lease->state != SMB2_OPLOCK_LEVEL_NONE) {
@@ -1372,6 +1373,9 @@ void smb_break_all_levII_oplock(struct ksmbd_work *work, struct ksmbd_file *fp,

rcu_read_lock();
list_for_each_entry_rcu(brk_op, &ci->m_op_list, op_entry) {
+ if (brk_op->conn == NULL)
+ continue;
+
if (!atomic_inc_not_zero(&brk_op->refcount))
continue;

@@ -1508,11 +1512,10 @@ void create_lease_buf(u8 *rbuf, struct lease *lease)
/**
* parse_lease_state() - parse lease context containted in file open request
* @open_req: buffer containing smb2 file open(create) request
- * @is_dir: whether leasing file is directory
*
* Return: oplock state, -ENOENT if create lease context not found
*/
-struct lease_ctx_info *parse_lease_state(void *open_req, bool is_dir)
+struct lease_ctx_info *parse_lease_state(void *open_req)
{
struct create_context *cc;
struct smb2_create_req *req = (struct smb2_create_req *)open_req;
@@ -1530,12 +1533,7 @@ struct lease_ctx_info *parse_lease_state(void *open_req, bool is_dir)
struct create_lease_v2 *lc = (struct create_lease_v2 *)cc;

memcpy(lreq->lease_key, lc->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE);
- if (is_dir) {
- lreq->req_state = lc->lcontext.LeaseState &
- ~SMB2_LEASE_WRITE_CACHING_LE;
- lreq->is_dir = true;
- } else
- lreq->req_state = lc->lcontext.LeaseState;
+ lreq->req_state = lc->lcontext.LeaseState;
lreq->flags = lc->lcontext.LeaseFlags;
lreq->epoch = lc->lcontext.Epoch;
lreq->duration = lc->lcontext.LeaseDuration;
@@ -1659,6 +1657,8 @@ void create_durable_v2_rsp_buf(char *cc, struct ksmbd_file *fp)
buf->Name[3] = 'Q';

buf->Timeout = cpu_to_le32(fp->durable_timeout);
+ if (fp->is_persistent)
+ buf->Flags = cpu_to_le32(SMB2_DHANDLE_FLAG_PERSISTENT);
}

/**
@@ -1826,3 +1826,71 @@ struct oplock_info *lookup_lease_in_table(struct ksmbd_conn *conn,
read_unlock(&lease_list_lock);
return ret_op;
}
+
+int smb2_check_durable_oplock(struct ksmbd_conn *conn,
+ struct ksmbd_share_config *share,
+ struct ksmbd_file *fp,
+ struct lease_ctx_info *lctx,
+ char *name)
+{
+ struct oplock_info *opinfo = opinfo_get(fp);
+ int ret = 0;
+
+ if (!opinfo)
+ return 0;
+
+ if (opinfo->is_lease == false) {
+ if (lctx) {
+ pr_err("create context include lease\n");
+ ret = -EBADF;
+ goto out;
+ }
+
+ if (opinfo->level != SMB2_OPLOCK_LEVEL_BATCH) {
+ pr_err("oplock level is not equal to SMB2_OPLOCK_LEVEL_BATCH\n");
+ ret = -EBADF;
+ }
+
+ goto out;
+ }
+
+ if (memcmp(conn->ClientGUID, fp->client_guid,
+ SMB2_CLIENT_GUID_SIZE)) {
+ ksmbd_debug(SMB, "Client guid of fp is not equal to the one of connction\n");
+ ret = -EBADF;
+ goto out;
+ }
+
+ if (!lctx) {
+ ksmbd_debug(SMB, "create context does not include lease\n");
+ ret = -EBADF;
+ goto out;
+ }
+
+ if (memcmp(opinfo->o_lease->lease_key, lctx->lease_key,
+ SMB2_LEASE_KEY_SIZE)) {
+ ksmbd_debug(SMB,
+ "lease key of fp does not match lease key in create context\n");
+ ret = -EBADF;
+ goto out;
+ }
+
+ if (!(opinfo->o_lease->state & SMB2_LEASE_HANDLE_CACHING_LE)) {
+ ksmbd_debug(SMB, "lease state does not contain SMB2_LEASE_HANDLE_CACHING\n");
+ ret = -EBADF;
+ goto out;
+ }
+
+ if (opinfo->o_lease->version != lctx->version) {
+ ksmbd_debug(SMB,
+ "lease version of fp does not match the one in create context\n");
+ ret = -EBADF;
+ goto out;
+ }
+
+ if (!ksmbd_inode_pending_delete(fp))
+ ret = ksmbd_validate_name_reconnect(share, fp, name);
+out:
+ opinfo_put(opinfo);
+ return ret;
+}
diff --git a/fs/smb/server/oplock.h b/fs/smb/server/oplock.h
index 5b93ea9196c01..e9da63f25b206 100644
--- a/fs/smb/server/oplock.h
+++ b/fs/smb/server/oplock.h
@@ -111,7 +111,7 @@ void opinfo_put(struct oplock_info *opinfo);

/* Lease related functions */
void create_lease_buf(u8 *rbuf, struct lease *lease);
-struct lease_ctx_info *parse_lease_state(void *open_req, bool is_dir);
+struct lease_ctx_info *parse_lease_state(void *open_req);
__u8 smb2_map_lease_to_oplock(__le32 lease_state);
int lease_read_to_write(struct oplock_info *opinfo);

@@ -130,4 +130,9 @@ void destroy_lease_table(struct ksmbd_conn *conn);
void smb_send_parent_lease_break_noti(struct ksmbd_file *fp,
struct lease_ctx_info *lctx);
void smb_lazy_parent_lease_break_close(struct ksmbd_file *fp);
+int smb2_check_durable_oplock(struct ksmbd_conn *conn,
+ struct ksmbd_share_config *share,
+ struct ksmbd_file *fp,
+ struct lease_ctx_info *lctx,
+ char *name);
#endif /* __KSMBD_OPLOCK_H */
diff --git a/fs/smb/server/smb2ops.c b/fs/smb/server/smb2ops.c
index 8600f32c981a1..606aa3c5189a2 100644
--- a/fs/smb/server/smb2ops.c
+++ b/fs/smb/server/smb2ops.c
@@ -261,6 +261,9 @@ void init_smb3_02_server(struct ksmbd_conn *conn)

if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB3_MULTICHANNEL)
conn->vals->capabilities |= SMB2_GLOBAL_CAP_MULTI_CHANNEL;
+
+ if (server_conf.flags & KSMBD_GLOBAL_FLAG_DURABLE_HANDLE)
+ conn->vals->capabilities |= SMB2_GLOBAL_CAP_PERSISTENT_HANDLES;
}

/**
@@ -283,6 +286,9 @@ int init_smb3_11_server(struct ksmbd_conn *conn)
if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB3_MULTICHANNEL)
conn->vals->capabilities |= SMB2_GLOBAL_CAP_MULTI_CHANNEL;

+ if (server_conf.flags & KSMBD_GLOBAL_FLAG_DURABLE_HANDLE)
+ conn->vals->capabilities |= SMB2_GLOBAL_CAP_PERSISTENT_HANDLES;
+
INIT_LIST_HEAD(&conn->preauth_sess_table);
return 0;
}
diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index 61717917db765..218adb3c55816 100644
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -2622,6 +2622,165 @@ static void ksmbd_acls_fattr(struct smb_fattr *fattr,
}
}

+enum {
+ DURABLE_RECONN_V2 = 1,
+ DURABLE_RECONN,
+ DURABLE_REQ_V2,
+ DURABLE_REQ,
+};
+
+struct durable_info {
+ struct ksmbd_file *fp;
+ unsigned short int type;
+ bool persistent;
+ bool reconnected;
+ unsigned int timeout;
+ char *CreateGuid;
+};
+
+static int parse_durable_handle_context(struct ksmbd_work *work,
+ struct smb2_create_req *req,
+ struct lease_ctx_info *lc,
+ struct durable_info *dh_info)
+{
+ struct ksmbd_conn *conn = work->conn;
+ struct create_context *context;
+ int dh_idx, err = 0;
+ u64 persistent_id = 0;
+ int req_op_level;
+ static const char * const durable_arr[] = {"DH2C", "DHnC", "DH2Q", "DHnQ"};
+
+ req_op_level = req->RequestedOplockLevel;
+ for (dh_idx = DURABLE_RECONN_V2; dh_idx <= ARRAY_SIZE(durable_arr);
+ dh_idx++) {
+ context = smb2_find_context_vals(req, durable_arr[dh_idx - 1], 4);
+ if (IS_ERR(context)) {
+ err = PTR_ERR(context);
+ goto out;
+ }
+ if (!context)
+ continue;
+
+ switch (dh_idx) {
+ case DURABLE_RECONN_V2:
+ {
+ struct create_durable_reconn_v2_req *recon_v2;
+
+ if (dh_info->type == DURABLE_RECONN ||
+ dh_info->type == DURABLE_REQ_V2) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ recon_v2 = (struct create_durable_reconn_v2_req *)context;
+ persistent_id = recon_v2->Fid.PersistentFileId;
+ dh_info->fp = ksmbd_lookup_durable_fd(persistent_id);
+ if (!dh_info->fp) {
+ ksmbd_debug(SMB, "Failed to get durable handle state\n");
+ err = -EBADF;
+ goto out;
+ }
+
+ if (memcmp(dh_info->fp->create_guid, recon_v2->CreateGuid,
+ SMB2_CREATE_GUID_SIZE)) {
+ err = -EBADF;
+ ksmbd_put_durable_fd(dh_info->fp);
+ goto out;
+ }
+
+ dh_info->type = dh_idx;
+ dh_info->reconnected = true;
+ ksmbd_debug(SMB,
+ "reconnect v2 Persistent-id from reconnect = %llu\n",
+ persistent_id);
+ break;
+ }
+ case DURABLE_RECONN:
+ {
+ struct create_durable_reconn_req *recon;
+
+ if (dh_info->type == DURABLE_RECONN_V2 ||
+ dh_info->type == DURABLE_REQ_V2) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ recon = (struct create_durable_reconn_req *)context;
+ persistent_id = recon->Data.Fid.PersistentFileId;
+ dh_info->fp = ksmbd_lookup_durable_fd(persistent_id);
+ if (!dh_info->fp) {
+ ksmbd_debug(SMB, "Failed to get durable handle state\n");
+ err = -EBADF;
+ goto out;
+ }
+
+ dh_info->type = dh_idx;
+ dh_info->reconnected = true;
+ ksmbd_debug(SMB, "reconnect Persistent-id from reconnect = %llu\n",
+ persistent_id);
+ break;
+ }
+ case DURABLE_REQ_V2:
+ {
+ struct create_durable_req_v2 *durable_v2_blob;
+
+ if (dh_info->type == DURABLE_RECONN ||
+ dh_info->type == DURABLE_RECONN_V2) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ durable_v2_blob =
+ (struct create_durable_req_v2 *)context;
+ ksmbd_debug(SMB, "Request for durable v2 open\n");
+ dh_info->fp = ksmbd_lookup_fd_cguid(durable_v2_blob->CreateGuid);
+ if (dh_info->fp) {
+ if (!memcmp(conn->ClientGUID, dh_info->fp->client_guid,
+ SMB2_CLIENT_GUID_SIZE)) {
+ if (!(req->hdr.Flags & SMB2_FLAGS_REPLAY_OPERATION)) {
+ err = -ENOEXEC;
+ goto out;
+ }
+
+ dh_info->fp->conn = conn;
+ dh_info->reconnected = true;
+ goto out;
+ }
+ }
+
+ if (((lc && (lc->req_state & SMB2_LEASE_HANDLE_CACHING_LE)) ||
+ req_op_level == SMB2_OPLOCK_LEVEL_BATCH)) {
+ dh_info->CreateGuid =
+ durable_v2_blob->CreateGuid;
+ dh_info->persistent =
+ le32_to_cpu(durable_v2_blob->Flags);
+ dh_info->timeout =
+ le32_to_cpu(durable_v2_blob->Timeout);
+ dh_info->type = dh_idx;
+ }
+ break;
+ }
+ case DURABLE_REQ:
+ if (dh_info->type == DURABLE_RECONN)
+ goto out;
+ if (dh_info->type == DURABLE_RECONN_V2 ||
+ dh_info->type == DURABLE_REQ_V2) {
+ err = -EINVAL;
+ goto out;
+ }
+
+ if (((lc && (lc->req_state & SMB2_LEASE_HANDLE_CACHING_LE)) ||
+ req_op_level == SMB2_OPLOCK_LEVEL_BATCH)) {
+ ksmbd_debug(SMB, "Request for durable open\n");
+ dh_info->type = dh_idx;
+ }
+ }
+ }
+
+out:
+ return err;
+}
+
/**
* smb2_open() - handler for smb file open request
* @work: smb work containing request buffer
@@ -2645,6 +2804,7 @@ int smb2_open(struct ksmbd_work *work)
struct lease_ctx_info *lc = NULL;
struct create_ea_buf_req *ea_buf = NULL;
struct oplock_info *opinfo;
+ struct durable_info dh_info = {0};
__le32 *next_ptr = NULL;
int req_op_level = 0, open_flags = 0, may_flags = 0, file_info = 0;
int rc = 0;
@@ -2725,6 +2885,49 @@ int smb2_open(struct ksmbd_work *work)
}
}

+ req_op_level = req->RequestedOplockLevel;
+
+ if (server_conf.flags & KSMBD_GLOBAL_FLAG_DURABLE_HANDLE &&
+ req->CreateContextsOffset) {
+ lc = parse_lease_state(req);
+ rc = parse_durable_handle_context(work, req, lc, &dh_info);
+ if (rc) {
+ ksmbd_debug(SMB, "error parsing durable handle context\n");
+ goto err_out2;
+ }
+
+ if (dh_info.reconnected == true) {
+ rc = smb2_check_durable_oplock(conn, share, dh_info.fp, lc, name);
+ if (rc) {
+ ksmbd_put_durable_fd(dh_info.fp);
+ goto err_out2;
+ }
+
+ rc = ksmbd_reopen_durable_fd(work, dh_info.fp);
+ if (rc) {
+ ksmbd_put_durable_fd(dh_info.fp);
+ goto err_out2;
+ }
+
+ if (ksmbd_override_fsids(work)) {
+ rc = -ENOMEM;
+ ksmbd_put_durable_fd(dh_info.fp);
+ goto err_out2;
+ }
+
+ fp = dh_info.fp;
+ file_info = FILE_OPENED;
+
+ rc = ksmbd_vfs_getattr(&fp->filp->f_path, &stat);
+ if (rc)
+ goto err_out2;
+
+ ksmbd_put_durable_fd(fp);
+ goto reconnected_fp;
+ }
+ } else if (req_op_level == SMB2_OPLOCK_LEVEL_LEASE)
+ lc = parse_lease_state(req);
+
if (le32_to_cpu(req->ImpersonationLevel) > le32_to_cpu(IL_DELEGATE)) {
pr_err("Invalid impersonationlevel : 0x%x\n",
le32_to_cpu(req->ImpersonationLevel));
@@ -3187,10 +3390,6 @@ int smb2_open(struct ksmbd_work *work)
need_truncate = 1;
}

- req_op_level = req->RequestedOplockLevel;
- if (req_op_level == SMB2_OPLOCK_LEVEL_LEASE)
- lc = parse_lease_state(req, S_ISDIR(file_inode(filp)->i_mode));
-
share_ret = ksmbd_smb_check_shared_mode(fp->filp, fp);
if (!test_share_config_flag(work->tcon->share_conf, KSMBD_SHARE_FLAG_OPLOCKS) ||
(req_op_level == SMB2_OPLOCK_LEVEL_LEASE &&
@@ -3201,6 +3400,11 @@ int smb2_open(struct ksmbd_work *work)
}
} else {
if (req_op_level == SMB2_OPLOCK_LEVEL_LEASE) {
+ if (S_ISDIR(file_inode(filp)->i_mode)) {
+ lc->req_state &= ~SMB2_LEASE_WRITE_CACHING_LE;
+ lc->is_dir = true;
+ }
+
/*
* Compare parent lease using parent key. If there is no
* a lease that has same parent key, Send lease break
@@ -3297,6 +3501,24 @@ int smb2_open(struct ksmbd_work *work)

memcpy(fp->client_guid, conn->ClientGUID, SMB2_CLIENT_GUID_SIZE);

+ if (dh_info.type == DURABLE_REQ_V2 || dh_info.type == DURABLE_REQ) {
+ if (dh_info.type == DURABLE_REQ_V2 && dh_info.persistent)
+ fp->is_persistent = true;
+ else
+ fp->is_durable = true;
+
+ if (dh_info.type == DURABLE_REQ_V2) {
+ memcpy(fp->create_guid, dh_info.CreateGuid,
+ SMB2_CREATE_GUID_SIZE);
+ if (dh_info.timeout)
+ fp->durable_timeout = min(dh_info.timeout,
+ 300000);
+ else
+ fp->durable_timeout = 60;
+ }
+ }
+
+reconnected_fp:
rsp->StructureSize = cpu_to_le16(89);
rcu_read_lock();
opinfo = rcu_dereference(fp->f_opinfo);
@@ -3383,6 +3605,33 @@ int smb2_open(struct ksmbd_work *work)
next_off = conn->vals->create_disk_id_size;
}

+ if (dh_info.type == DURABLE_REQ || dh_info.type == DURABLE_REQ_V2) {
+ struct create_context *durable_ccontext;
+
+ durable_ccontext = (struct create_context *)(rsp->Buffer +
+ le32_to_cpu(rsp->CreateContextsLength));
+ contxt_cnt++;
+ if (dh_info.type == DURABLE_REQ) {
+ create_durable_rsp_buf(rsp->Buffer +
+ le32_to_cpu(rsp->CreateContextsLength));
+ le32_add_cpu(&rsp->CreateContextsLength,
+ conn->vals->create_durable_size);
+ iov_len += conn->vals->create_durable_size;
+ } else {
+ create_durable_v2_rsp_buf(rsp->Buffer +
+ le32_to_cpu(rsp->CreateContextsLength),
+ fp);
+ le32_add_cpu(&rsp->CreateContextsLength,
+ conn->vals->create_durable_v2_size);
+ iov_len += conn->vals->create_durable_v2_size;
+ }
+
+ if (next_ptr)
+ *next_ptr = cpu_to_le32(next_off);
+ next_ptr = &durable_ccontext->Next;
+ next_off = conn->vals->create_durable_size;
+ }
+
if (posix_ctxt) {
contxt_cnt++;
create_posix_rsp_buf(rsp->Buffer +
diff --git a/fs/smb/server/smb2pdu.h b/fs/smb/server/smb2pdu.h
index d12cfd3b09278..bd1d2a0e9203a 100644
--- a/fs/smb/server/smb2pdu.h
+++ b/fs/smb/server/smb2pdu.h
@@ -72,6 +72,18 @@ struct create_durable_req_v2 {
__u8 CreateGuid[16];
} __packed;

+struct create_durable_reconn_req {
+ struct create_context ccontext;
+ __u8 Name[8];
+ union {
+ __u8 Reserved[16];
+ struct {
+ __u64 PersistentFileId;
+ __u64 VolatileFileId;
+ } Fid;
+ } Data;
+} __packed;
+
struct create_durable_reconn_v2_req {
struct create_context ccontext;
__u8 Name[8];
@@ -98,6 +110,9 @@ struct create_durable_rsp {
} Data;
} __packed;

+/* See MS-SMB2 2.2.13.2.11 */
+/* Flags */
+#define SMB2_DHANDLE_FLAG_PERSISTENT 0x00000002
struct create_durable_v2_rsp {
struct create_context ccontext;
__u8 Name[8];
diff --git a/fs/smb/server/vfs_cache.c b/fs/smb/server/vfs_cache.c
index 4e82ff627d122..030f70700036c 100644
--- a/fs/smb/server/vfs_cache.c
+++ b/fs/smb/server/vfs_cache.c
@@ -305,7 +305,8 @@ static void __ksmbd_close_fd(struct ksmbd_file_table *ft, struct ksmbd_file *fp)

fd_limit_close();
__ksmbd_remove_durable_fd(fp);
- __ksmbd_remove_fd(ft, fp);
+ if (ft)
+ __ksmbd_remove_fd(ft, fp);

close_id_del_oplock(fp);
filp = fp->filp;
@@ -465,11 +466,32 @@ struct ksmbd_file *ksmbd_lookup_fd_slow(struct ksmbd_work *work, u64 id,
return fp;
}

-struct ksmbd_file *ksmbd_lookup_durable_fd(unsigned long long id)
+struct ksmbd_file *ksmbd_lookup_global_fd(unsigned long long id)
{
return __ksmbd_lookup_fd(&global_ft, id);
}

+struct ksmbd_file *ksmbd_lookup_durable_fd(unsigned long long id)
+{
+ struct ksmbd_file *fp;
+
+ fp = __ksmbd_lookup_fd(&global_ft, id);
+ if (fp && fp->conn) {
+ ksmbd_put_durable_fd(fp);
+ fp = NULL;
+ }
+
+ return fp;
+}
+
+void ksmbd_put_durable_fd(struct ksmbd_file *fp)
+{
+ if (!atomic_dec_and_test(&fp->refcount))
+ return;
+
+ __ksmbd_close_fd(NULL, fp);
+}
+
struct ksmbd_file *ksmbd_lookup_fd_cguid(char *cguid)
{
struct ksmbd_file *fp = NULL;
@@ -639,6 +661,32 @@ __close_file_table_ids(struct ksmbd_file_table *ft,
return num;
}

+static inline bool is_reconnectable(struct ksmbd_file *fp)
+{
+ struct oplock_info *opinfo = opinfo_get(fp);
+ bool reconn = false;
+
+ if (!opinfo)
+ return false;
+
+ if (opinfo->op_state != OPLOCK_STATE_NONE) {
+ opinfo_put(opinfo);
+ return false;
+ }
+
+ if (fp->is_resilient || fp->is_persistent)
+ reconn = true;
+ else if (fp->is_durable && opinfo->is_lease &&
+ opinfo->o_lease->state & SMB2_LEASE_HANDLE_CACHING_LE)
+ reconn = true;
+
+ else if (fp->is_durable && opinfo->level == SMB2_OPLOCK_LEVEL_BATCH)
+ reconn = true;
+
+ opinfo_put(opinfo);
+ return reconn;
+}
+
static bool tree_conn_fd_check(struct ksmbd_tree_connect *tcon,
struct ksmbd_file *fp)
{
@@ -648,7 +696,28 @@ static bool tree_conn_fd_check(struct ksmbd_tree_connect *tcon,
static bool session_fd_check(struct ksmbd_tree_connect *tcon,
struct ksmbd_file *fp)
{
- return false;
+ struct ksmbd_inode *ci;
+ struct oplock_info *op;
+ struct ksmbd_conn *conn;
+
+ if (!is_reconnectable(fp))
+ return false;
+
+ conn = fp->conn;
+ ci = fp->f_ci;
+ write_lock(&ci->m_lock);
+ list_for_each_entry_rcu(op, &ci->m_op_list, op_entry) {
+ if (op->conn != conn)
+ continue;
+ op->conn = NULL;
+ }
+ write_unlock(&ci->m_lock);
+
+ fp->conn = NULL;
+ fp->tcon = NULL;
+ fp->volatile_id = KSMBD_NO_FID;
+
+ return true;
}

void ksmbd_close_tree_conn_fds(struct ksmbd_work *work)
@@ -687,6 +756,68 @@ void ksmbd_free_global_file_table(void)
ksmbd_destroy_file_table(&global_ft);
}

+int ksmbd_validate_name_reconnect(struct ksmbd_share_config *share,
+ struct ksmbd_file *fp, char *name)
+{
+ char *pathname, *ab_pathname;
+ int ret = 0;
+
+ pathname = kmalloc(PATH_MAX, GFP_KERNEL);
+ if (!pathname)
+ return -EACCES;
+
+ ab_pathname = d_path(&fp->filp->f_path, pathname, PATH_MAX);
+ if (IS_ERR(ab_pathname)) {
+ kfree(pathname);
+ return -EACCES;
+ }
+
+ if (name && strcmp(&ab_pathname[share->path_sz + 1], name)) {
+ ksmbd_debug(SMB, "invalid name reconnect %s\n", name);
+ ret = -EINVAL;
+ }
+
+ kfree(pathname);
+
+ return ret;
+}
+
+int ksmbd_reopen_durable_fd(struct ksmbd_work *work, struct ksmbd_file *fp)
+{
+ struct ksmbd_inode *ci;
+ struct oplock_info *op;
+
+ if (!fp->is_durable || fp->conn || fp->tcon) {
+ pr_err("Invalid durable fd [%p:%p]\n", fp->conn, fp->tcon);
+ return -EBADF;
+ }
+
+ if (has_file_id(fp->volatile_id)) {
+ pr_err("Still in use durable fd: %llu\n", fp->volatile_id);
+ return -EBADF;
+ }
+
+ fp->conn = work->conn;
+ fp->tcon = work->tcon;
+
+ ci = fp->f_ci;
+ write_lock(&ci->m_lock);
+ list_for_each_entry_rcu(op, &ci->m_op_list, op_entry) {
+ if (op->conn)
+ continue;
+ op->conn = fp->conn;
+ }
+ write_unlock(&ci->m_lock);
+
+ __open_id(&work->sess->file_table, fp, OPEN_ID_TYPE_VOLATILE_ID);
+ if (!has_file_id(fp->volatile_id)) {
+ fp->conn = NULL;
+ fp->tcon = NULL;
+ return -EBADF;
+ }
+ return 0;
+}
+
int ksmbd_init_file_table(struct ksmbd_file_table *ft)
{
ft->idr = kzalloc(sizeof(struct idr), GFP_KERNEL);
diff --git a/fs/smb/server/vfs_cache.h b/fs/smb/server/vfs_cache.h
index a528f0cc775ae..ed44fb4e18e79 100644
--- a/fs/smb/server/vfs_cache.h
+++ b/fs/smb/server/vfs_cache.h
@@ -14,6 +14,7 @@
#include <linux/workqueue.h>

#include "vfs.h"
+#include "mgmt/share_config.h"

/* Windows style file permissions for extended response */
#define FILE_GENERIC_ALL 0x1F01FF
@@ -106,6 +107,9 @@ struct ksmbd_file {
int dot_dotdot[2];
unsigned int f_state;
bool reserve_lease_break;
+ bool is_durable;
+ bool is_persistent;
+ bool is_resilient;
};

static inline void set_ctx_actor(struct dir_context *ctx,
@@ -141,7 +145,9 @@ struct ksmbd_file *ksmbd_lookup_fd_slow(struct ksmbd_work *work, u64 id,
void ksmbd_fd_put(struct ksmbd_work *work, struct ksmbd_file *fp);
struct ksmbd_inode *ksmbd_inode_lookup_lock(struct dentry *d);
void ksmbd_inode_put(struct ksmbd_inode *ci);
+struct ksmbd_file *ksmbd_lookup_global_fd(unsigned long long id);
struct ksmbd_file *ksmbd_lookup_durable_fd(unsigned long long id);
+void ksmbd_put_durable_fd(struct ksmbd_file *fp);
struct ksmbd_file *ksmbd_lookup_fd_cguid(char *cguid);
struct ksmbd_file *ksmbd_lookup_fd_inode(struct dentry *dentry);
unsigned int ksmbd_open_durable_fd(struct ksmbd_file *fp);
@@ -173,6 +179,9 @@ void ksmbd_set_inode_pending_delete(struct ksmbd_file *fp);
void ksmbd_clear_inode_pending_delete(struct ksmbd_file *fp);
void ksmbd_fd_set_delete_on_close(struct ksmbd_file *fp,
int file_info);
+int ksmbd_reopen_durable_fd(struct ksmbd_work *work, struct ksmbd_file *fp);
+int ksmbd_validate_name_reconnect(struct ksmbd_share_config *share,
+ struct ksmbd_file *fp, char *name);
int ksmbd_init_file_cache(void);
void ksmbd_exit_file_cache(void);
#endif /* __VFS_CACHE_H__ */
--
2.43.0