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authorLinus Torvalds <torvalds@linux-foundation.org>2023-12-12 10:30:10 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2023-12-12 10:30:10 -0800
commit8b8cd4beea4f6c68092736c544a797dcd5e094c5 (patch)
tree648c926bb525d670975e5a30e8e701a68cd56d40 /fs
parent26aff849438cebcd05f1a647390c4aa700d5c0f1 (diff)
parent13736654481198e519059d4a2e2e3b20fa9fdb3e (diff)
Merge tag '6.7-rc5-ksmbd-server-fixes' of git://git.samba.org/ksmbd
Pull smb server fixes from Steve French: - Memory leak fix (in lock error path) - Two fixes for create with allocation size - FIx for potential UAF in lease break error path - Five directory lease (caching) fixes found during additional recent testing * tag '6.7-rc5-ksmbd-server-fixes' of git://git.samba.org/ksmbd: ksmbd: fix wrong name of SMB2_CREATE_ALLOCATION_SIZE ksmbd: fix wrong allocation size update in smb2_open() ksmbd: avoid duplicate opinfo_put() call on error of smb21_lease_break_ack() ksmbd: lazy v2 lease break on smb2_write() ksmbd: send v2 lease break notification for directory ksmbd: downgrade RWH lease caching state to RH for directory ksmbd: set v2 lease capability ksmbd: set epoch in create context v2 lease ksmbd: fix memory leak in smb2_lock()
Diffstat (limited to 'fs')
-rw-r--r--fs/smb/common/smb2pdu.h3
-rw-r--r--fs/smb/server/oplock.c115
-rw-r--r--fs/smb/server/oplock.h8
-rw-r--r--fs/smb/server/smb2ops.c9
-rw-r--r--fs/smb/server/smb2pdu.c62
-rw-r--r--fs/smb/server/vfs.c3
-rw-r--r--fs/smb/server/vfs_cache.c13
-rw-r--r--fs/smb/server/vfs_cache.h3
8 files changed, 171 insertions, 45 deletions
diff --git a/fs/smb/common/smb2pdu.h b/fs/smb/common/smb2pdu.h
index 9fbaaa387dcc..57f2343164a3 100644
--- a/fs/smb/common/smb2pdu.h
+++ b/fs/smb/common/smb2pdu.h
@@ -1145,7 +1145,7 @@ struct smb2_server_client_notification {
#define SMB2_CREATE_SD_BUFFER "SecD" /* security descriptor */
#define SMB2_CREATE_DURABLE_HANDLE_REQUEST "DHnQ"
#define SMB2_CREATE_DURABLE_HANDLE_RECONNECT "DHnC"
-#define SMB2_CREATE_ALLOCATION_SIZE "AISi"
+#define SMB2_CREATE_ALLOCATION_SIZE "AlSi"
#define SMB2_CREATE_QUERY_MAXIMAL_ACCESS_REQUEST "MxAc"
#define SMB2_CREATE_TIMEWARP_REQUEST "TWrp"
#define SMB2_CREATE_QUERY_ON_DISK_ID "QFid"
@@ -1253,6 +1253,7 @@ struct create_mxac_rsp {
#define SMB2_LEASE_WRITE_CACHING_LE cpu_to_le32(0x04)
#define SMB2_LEASE_FLAG_BREAK_IN_PROGRESS_LE cpu_to_le32(0x02)
+#define SMB2_LEASE_FLAG_PARENT_LEASE_KEY_SET_LE cpu_to_le32(0x04)
#define SMB2_LEASE_KEY_SIZE 16
diff --git a/fs/smb/server/oplock.c b/fs/smb/server/oplock.c
index 50c68beb71d6..562b180459a1 100644
--- a/fs/smb/server/oplock.c
+++ b/fs/smb/server/oplock.c
@@ -102,9 +102,10 @@ static int alloc_lease(struct oplock_info *opinfo, struct lease_ctx_info *lctx)
lease->new_state = 0;
lease->flags = lctx->flags;
lease->duration = lctx->duration;
+ lease->is_dir = lctx->is_dir;
memcpy(lease->parent_lease_key, lctx->parent_lease_key, SMB2_LEASE_KEY_SIZE);
lease->version = lctx->version;
- lease->epoch = 0;
+ lease->epoch = le16_to_cpu(lctx->epoch);
INIT_LIST_HEAD(&opinfo->lease_entry);
opinfo->o_lease = lease;
@@ -395,8 +396,8 @@ void close_id_del_oplock(struct ksmbd_file *fp)
{
struct oplock_info *opinfo;
- if (S_ISDIR(file_inode(fp->filp)->i_mode))
- return;
+ if (fp->reserve_lease_break)
+ smb_lazy_parent_lease_break_close(fp);
opinfo = opinfo_get(fp);
if (!opinfo)
@@ -543,12 +544,13 @@ static struct oplock_info *same_client_has_lease(struct ksmbd_inode *ci,
/* upgrading lease */
if ((atomic_read(&ci->op_count) +
atomic_read(&ci->sop_count)) == 1) {
- if (lease->state ==
- (lctx->req_state & lease->state)) {
+ if (lease->state != SMB2_LEASE_NONE_LE &&
+ lease->state == (lctx->req_state & lease->state)) {
lease->state |= lctx->req_state;
if (lctx->req_state &
SMB2_LEASE_WRITE_CACHING_LE)
lease_read_to_write(opinfo);
+
}
} else if ((atomic_read(&ci->op_count) +
atomic_read(&ci->sop_count)) > 1) {
@@ -900,7 +902,8 @@ static int oplock_break(struct oplock_info *brk_opinfo, int req_op_level)
lease->new_state =
SMB2_LEASE_READ_CACHING_LE;
} else {
- if (lease->state & SMB2_LEASE_HANDLE_CACHING_LE)
+ if (lease->state & SMB2_LEASE_HANDLE_CACHING_LE &&
+ !lease->is_dir)
lease->new_state =
SMB2_LEASE_READ_CACHING_LE;
else
@@ -1032,6 +1035,7 @@ static void copy_lease(struct oplock_info *op1, struct oplock_info *op2)
SMB2_LEASE_KEY_SIZE);
lease2->duration = lease1->duration;
lease2->flags = lease1->flags;
+ lease2->epoch = lease1->epoch++;
}
static int add_lease_global_list(struct oplock_info *opinfo)
@@ -1081,6 +1085,89 @@ static void set_oplock_level(struct oplock_info *opinfo, int level,
}
}
+void smb_send_parent_lease_break_noti(struct ksmbd_file *fp,
+ struct lease_ctx_info *lctx)
+{
+ struct oplock_info *opinfo;
+ struct ksmbd_inode *p_ci = NULL;
+
+ if (lctx->version != 2)
+ return;
+
+ p_ci = ksmbd_inode_lookup_lock(fp->filp->f_path.dentry->d_parent);
+ if (!p_ci)
+ return;
+
+ read_lock(&p_ci->m_lock);
+ list_for_each_entry(opinfo, &p_ci->m_op_list, op_entry) {
+ if (!opinfo->is_lease)
+ continue;
+
+ if (opinfo->o_lease->state != SMB2_OPLOCK_LEVEL_NONE &&
+ (!(lctx->flags & SMB2_LEASE_FLAG_PARENT_LEASE_KEY_SET_LE) ||
+ !compare_guid_key(opinfo, fp->conn->ClientGUID,
+ lctx->parent_lease_key))) {
+ if (!atomic_inc_not_zero(&opinfo->refcount))
+ continue;
+
+ atomic_inc(&opinfo->conn->r_count);
+ if (ksmbd_conn_releasing(opinfo->conn)) {
+ atomic_dec(&opinfo->conn->r_count);
+ continue;
+ }
+
+ read_unlock(&p_ci->m_lock);
+ oplock_break(opinfo, SMB2_OPLOCK_LEVEL_NONE);
+ opinfo_conn_put(opinfo);
+ read_lock(&p_ci->m_lock);
+ }
+ }
+ read_unlock(&p_ci->m_lock);
+
+ ksmbd_inode_put(p_ci);
+}
+
+void smb_lazy_parent_lease_break_close(struct ksmbd_file *fp)
+{
+ struct oplock_info *opinfo;
+ struct ksmbd_inode *p_ci = NULL;
+
+ rcu_read_lock();
+ opinfo = rcu_dereference(fp->f_opinfo);
+ rcu_read_unlock();
+
+ if (!opinfo->is_lease || opinfo->o_lease->version != 2)
+ return;
+
+ p_ci = ksmbd_inode_lookup_lock(fp->filp->f_path.dentry->d_parent);
+ if (!p_ci)
+ return;
+
+ read_lock(&p_ci->m_lock);
+ list_for_each_entry(opinfo, &p_ci->m_op_list, op_entry) {
+ if (!opinfo->is_lease)
+ continue;
+
+ if (opinfo->o_lease->state != SMB2_OPLOCK_LEVEL_NONE) {
+ if (!atomic_inc_not_zero(&opinfo->refcount))
+ continue;
+
+ atomic_inc(&opinfo->conn->r_count);
+ if (ksmbd_conn_releasing(opinfo->conn)) {
+ atomic_dec(&opinfo->conn->r_count);
+ continue;
+ }
+ read_unlock(&p_ci->m_lock);
+ oplock_break(opinfo, SMB2_OPLOCK_LEVEL_NONE);
+ opinfo_conn_put(opinfo);
+ read_lock(&p_ci->m_lock);
+ }
+ }
+ read_unlock(&p_ci->m_lock);
+
+ ksmbd_inode_put(p_ci);
+}
+
/**
* smb_grant_oplock() - handle oplock/lease request on file open
* @work: smb work
@@ -1104,10 +1191,6 @@ int smb_grant_oplock(struct ksmbd_work *work, int req_op_level, u64 pid,
bool prev_op_has_lease;
__le32 prev_op_state = 0;
- /* not support directory lease */
- if (S_ISDIR(file_inode(fp->filp)->i_mode))
- return 0;
-
opinfo = alloc_opinfo(work, pid, tid);
if (!opinfo)
return -ENOMEM;
@@ -1364,6 +1447,7 @@ void create_lease_buf(u8 *rbuf, struct lease *lease)
memcpy(buf->lcontext.LeaseKey, lease->lease_key,
SMB2_LEASE_KEY_SIZE);
buf->lcontext.LeaseFlags = lease->flags;
+ buf->lcontext.Epoch = cpu_to_le16(++lease->epoch);
buf->lcontext.LeaseState = lease->state;
memcpy(buf->lcontext.ParentLeaseKey, lease->parent_lease_key,
SMB2_LEASE_KEY_SIZE);
@@ -1400,10 +1484,11 @@ 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)
+struct lease_ctx_info *parse_lease_state(void *open_req, bool is_dir)
{
struct create_context *cc;
struct smb2_create_req *req = (struct smb2_create_req *)open_req;
@@ -1421,8 +1506,14 @@ struct lease_ctx_info *parse_lease_state(void *open_req)
struct create_lease_v2 *lc = (struct create_lease_v2 *)cc;
memcpy(lreq->lease_key, lc->lcontext.LeaseKey, SMB2_LEASE_KEY_SIZE);
- lreq->req_state = lc->lcontext.LeaseState;
+ 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->flags = lc->lcontext.LeaseFlags;
+ lreq->epoch = lc->lcontext.Epoch;
lreq->duration = lc->lcontext.LeaseDuration;
memcpy(lreq->parent_lease_key, lc->lcontext.ParentLeaseKey,
SMB2_LEASE_KEY_SIZE);
diff --git a/fs/smb/server/oplock.h b/fs/smb/server/oplock.h
index 4b0fe6da7694..5b93ea9196c0 100644
--- a/fs/smb/server/oplock.h
+++ b/fs/smb/server/oplock.h
@@ -34,7 +34,9 @@ struct lease_ctx_info {
__le32 flags;
__le64 duration;
__u8 parent_lease_key[SMB2_LEASE_KEY_SIZE];
+ __le16 epoch;
int version;
+ bool is_dir;
};
struct lease_table {
@@ -53,6 +55,7 @@ struct lease {
__u8 parent_lease_key[SMB2_LEASE_KEY_SIZE];
int version;
unsigned short epoch;
+ bool is_dir;
struct lease_table *l_lb;
};
@@ -108,7 +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);
+struct lease_ctx_info *parse_lease_state(void *open_req, bool is_dir);
__u8 smb2_map_lease_to_oplock(__le32 lease_state);
int lease_read_to_write(struct oplock_info *opinfo);
@@ -124,4 +127,7 @@ struct oplock_info *lookup_lease_in_table(struct ksmbd_conn *conn,
int find_same_lease_key(struct ksmbd_session *sess, struct ksmbd_inode *ci,
struct lease_ctx_info *lctx);
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);
#endif /* __KSMBD_OPLOCK_H */
diff --git a/fs/smb/server/smb2ops.c b/fs/smb/server/smb2ops.c
index aed7704a0672..27a9dce3e03a 100644
--- a/fs/smb/server/smb2ops.c
+++ b/fs/smb/server/smb2ops.c
@@ -221,7 +221,8 @@ void init_smb3_0_server(struct ksmbd_conn *conn)
conn->signing_algorithm = SIGNING_ALG_AES_CMAC_LE;
if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_LEASES)
- conn->vals->capabilities |= SMB2_GLOBAL_CAP_LEASING;
+ conn->vals->capabilities |= SMB2_GLOBAL_CAP_LEASING |
+ SMB2_GLOBAL_CAP_DIRECTORY_LEASING;
if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION &&
conn->cli_cap & SMB2_GLOBAL_CAP_ENCRYPTION)
@@ -245,7 +246,8 @@ void init_smb3_02_server(struct ksmbd_conn *conn)
conn->signing_algorithm = SIGNING_ALG_AES_CMAC_LE;
if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_LEASES)
- conn->vals->capabilities |= SMB2_GLOBAL_CAP_LEASING;
+ conn->vals->capabilities |= SMB2_GLOBAL_CAP_LEASING |
+ SMB2_GLOBAL_CAP_DIRECTORY_LEASING;
if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION ||
(!(server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION_OFF) &&
@@ -270,7 +272,8 @@ int init_smb3_11_server(struct ksmbd_conn *conn)
conn->signing_algorithm = SIGNING_ALG_AES_CMAC_LE;
if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_LEASES)
- conn->vals->capabilities |= SMB2_GLOBAL_CAP_LEASING;
+ conn->vals->capabilities |= SMB2_GLOBAL_CAP_LEASING |
+ SMB2_GLOBAL_CAP_DIRECTORY_LEASING;
if (server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION ||
(!(server_conf.flags & KSMBD_GLOBAL_FLAG_SMB2_ENCRYPTION_OFF) &&
diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index d369b98a6e10..652ab429bf2e 100644
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -2516,7 +2516,7 @@ static void smb2_new_xattrs(struct ksmbd_tree_connect *tcon, const struct path *
da.flags = XATTR_DOSINFO_ATTRIB | XATTR_DOSINFO_CREATE_TIME |
XATTR_DOSINFO_ITIME;
- rc = ksmbd_vfs_set_dos_attrib_xattr(mnt_idmap(path->mnt), path, &da, false);
+ rc = ksmbd_vfs_set_dos_attrib_xattr(mnt_idmap(path->mnt), path, &da, true);
if (rc)
ksmbd_debug(SMB, "failed to store file attribute into xattr\n");
}
@@ -2732,10 +2732,6 @@ int smb2_open(struct ksmbd_work *work)
}
}
- req_op_level = req->RequestedOplockLevel;
- 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));
@@ -3189,23 +3185,6 @@ int smb2_open(struct ksmbd_work *work)
goto err_out;
}
- rc = ksmbd_vfs_getattr(&path, &stat);
- if (rc)
- goto err_out;
-
- if (stat.result_mask & STATX_BTIME)
- fp->create_time = ksmbd_UnixTimeToNT(stat.btime);
- else
- fp->create_time = ksmbd_UnixTimeToNT(stat.ctime);
- if (req->FileAttributes || fp->f_ci->m_fattr == 0)
- fp->f_ci->m_fattr =
- cpu_to_le32(smb2_get_dos_mode(&stat, le32_to_cpu(req->FileAttributes)));
-
- if (!created)
- smb2_update_xattrs(tcon, &path, fp);
- else
- smb2_new_xattrs(tcon, &path, fp);
-
if (file_present || created)
ksmbd_vfs_kern_path_unlock(&parent_path, &path);
@@ -3215,6 +3194,10 @@ 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 &&
@@ -3225,6 +3208,13 @@ int smb2_open(struct ksmbd_work *work)
}
} else {
if (req_op_level == SMB2_OPLOCK_LEVEL_LEASE) {
+ /*
+ * Compare parent lease using parent key. If there is no
+ * a lease that has same parent key, Send lease break
+ * notification.
+ */
+ smb_send_parent_lease_break_noti(fp, lc);
+
req_op_level = smb2_map_lease_to_oplock(lc->req_state);
ksmbd_debug(SMB,
"lease req for(%s) req oplock state 0x%x, lease state 0x%x\n",
@@ -3295,6 +3285,23 @@ int smb2_open(struct ksmbd_work *work)
}
}
+ rc = ksmbd_vfs_getattr(&path, &stat);
+ if (rc)
+ goto err_out1;
+
+ if (stat.result_mask & STATX_BTIME)
+ fp->create_time = ksmbd_UnixTimeToNT(stat.btime);
+ else
+ fp->create_time = ksmbd_UnixTimeToNT(stat.ctime);
+ if (req->FileAttributes || fp->f_ci->m_fattr == 0)
+ fp->f_ci->m_fattr =
+ cpu_to_le32(smb2_get_dos_mode(&stat, le32_to_cpu(req->FileAttributes)));
+
+ if (!created)
+ smb2_update_xattrs(tcon, &path, fp);
+ else
+ smb2_new_xattrs(tcon, &path, fp);
+
memcpy(fp->client_guid, conn->ClientGUID, SMB2_CLIENT_GUID_SIZE);
rsp->StructureSize = cpu_to_le16(89);
@@ -7080,6 +7087,7 @@ skip:
smb2_remove_blocked_lock,
argv);
if (rc) {
+ kfree(argv);
err = -ENOMEM;
goto out;
}
@@ -8211,6 +8219,11 @@ static void smb21_lease_break_ack(struct ksmbd_work *work)
le32_to_cpu(req->LeaseState));
}
+ if (ret < 0) {
+ rsp->hdr.Status = err;
+ goto err_out;
+ }
+
lease_state = lease->state;
opinfo->op_state = OPLOCK_STATE_NONE;
wake_up_interruptible_all(&opinfo->oplock_q);
@@ -8218,11 +8231,6 @@ static void smb21_lease_break_ack(struct ksmbd_work *work)
wake_up_interruptible_all(&opinfo->oplock_brk);
opinfo_put(opinfo);
- if (ret < 0) {
- rsp->hdr.Status = err;
- goto err_out;
- }
-
rsp->StructureSize = cpu_to_le16(36);
rsp->Reserved = 0;
rsp->Flags = 0;
diff --git a/fs/smb/server/vfs.c b/fs/smb/server/vfs.c
index 9091dcd7a310..4277750a6da1 100644
--- a/fs/smb/server/vfs.c
+++ b/fs/smb/server/vfs.c
@@ -517,6 +517,9 @@ int ksmbd_vfs_write(struct ksmbd_work *work, struct ksmbd_file *fp,
}
}
+ /* Reserve lease break for parent dir at closing time */
+ fp->reserve_lease_break = true;
+
/* Do we need to break any of a levelII oplock? */
smb_break_all_levII_oplock(work, fp, 1);
diff --git a/fs/smb/server/vfs_cache.c b/fs/smb/server/vfs_cache.c
index ddf233994ddb..4e82ff627d12 100644
--- a/fs/smb/server/vfs_cache.c
+++ b/fs/smb/server/vfs_cache.c
@@ -87,6 +87,17 @@ static struct ksmbd_inode *ksmbd_inode_lookup(struct ksmbd_file *fp)
return __ksmbd_inode_lookup(fp->filp->f_path.dentry);
}
+struct ksmbd_inode *ksmbd_inode_lookup_lock(struct dentry *d)
+{
+ struct ksmbd_inode *ci;
+
+ read_lock(&inode_hash_lock);
+ ci = __ksmbd_inode_lookup(d);
+ read_unlock(&inode_hash_lock);
+
+ return ci;
+}
+
int ksmbd_query_inode_status(struct dentry *dentry)
{
struct ksmbd_inode *ci;
@@ -199,7 +210,7 @@ static void ksmbd_inode_free(struct ksmbd_inode *ci)
kfree(ci);
}
-static void ksmbd_inode_put(struct ksmbd_inode *ci)
+void ksmbd_inode_put(struct ksmbd_inode *ci)
{
if (atomic_dec_and_test(&ci->m_count))
ksmbd_inode_free(ci);
diff --git a/fs/smb/server/vfs_cache.h b/fs/smb/server/vfs_cache.h
index 8325cf4527c4..a528f0cc775a 100644
--- a/fs/smb/server/vfs_cache.h
+++ b/fs/smb/server/vfs_cache.h
@@ -105,6 +105,7 @@ struct ksmbd_file {
struct ksmbd_readdir_data readdir_data;
int dot_dotdot[2];
unsigned int f_state;
+ bool reserve_lease_break;
};
static inline void set_ctx_actor(struct dir_context *ctx,
@@ -138,6 +139,8 @@ struct ksmbd_file *ksmbd_lookup_foreign_fd(struct ksmbd_work *work, u64 id);
struct ksmbd_file *ksmbd_lookup_fd_slow(struct ksmbd_work *work, u64 id,
u64 pid);
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_durable_fd(unsigned long long id);
struct ksmbd_file *ksmbd_lookup_fd_cguid(char *cguid);
struct ksmbd_file *ksmbd_lookup_fd_inode(struct dentry *dentry);