Merge tag '6.6-rc4-ksmbd-server-fixes' of git://git.samba.org/ksmbd
Pull smb server fixes from Steve French:
"Six SMB3 server fixes for various races found by RO0T Lab of Huawei:
- Fix oops when racing between oplock break ack and freeing file
- Simultaneous request fixes for parallel logoffs, and for parallel
lock requests
- Fixes for tree disconnect race, session expire race, and close/open
race"
* tag '6.6-rc4-ksmbd-server-fixes' of git://git.samba.org/ksmbd:
ksmbd: fix race condition between tree conn lookup and disconnect
ksmbd: fix race condition from parallel smb2 lock requests
ksmbd: fix race condition from parallel smb2 logoff requests
ksmbd: fix uaf in smb20_oplock_break_ack
ksmbd: fix race condition with fp
ksmbd: fix race condition between session lookup and expire
diff --git a/fs/smb/server/connection.c b/fs/smb/server/connection.c
index db7fa70..4b38c3a 100644
--- a/fs/smb/server/connection.c
+++ b/fs/smb/server/connection.c
@@ -84,6 +84,8 @@ struct ksmbd_conn *ksmbd_conn_alloc(void)
spin_lock_init(&conn->llist_lock);
INIT_LIST_HEAD(&conn->lock_list);
+ init_rwsem(&conn->session_lock);
+
down_write(&conn_list_lock);
list_add(&conn->conns_list, &conn_list);
up_write(&conn_list_lock);
diff --git a/fs/smb/server/connection.h b/fs/smb/server/connection.h
index ab2583f..3c00524 100644
--- a/fs/smb/server/connection.h
+++ b/fs/smb/server/connection.h
@@ -50,6 +50,7 @@ struct ksmbd_conn {
struct nls_table *local_nls;
struct unicode_map *um;
struct list_head conns_list;
+ struct rw_semaphore session_lock;
/* smb session 1 per user */
struct xarray sessions;
unsigned long last_active;
diff --git a/fs/smb/server/mgmt/tree_connect.c b/fs/smb/server/mgmt/tree_connect.c
index 408cddf..d2c81a8 100644
--- a/fs/smb/server/mgmt/tree_connect.c
+++ b/fs/smb/server/mgmt/tree_connect.c
@@ -73,7 +73,10 @@ ksmbd_tree_conn_connect(struct ksmbd_conn *conn, struct ksmbd_session *sess,
tree_conn->user = sess->user;
tree_conn->share_conf = sc;
+ tree_conn->t_state = TREE_NEW;
status.tree_conn = tree_conn;
+ atomic_set(&tree_conn->refcount, 1);
+ init_waitqueue_head(&tree_conn->refcount_q);
ret = xa_err(xa_store(&sess->tree_conns, tree_conn->id, tree_conn,
GFP_KERNEL));
@@ -93,14 +96,33 @@ ksmbd_tree_conn_connect(struct ksmbd_conn *conn, struct ksmbd_session *sess,
return status;
}
+void ksmbd_tree_connect_put(struct ksmbd_tree_connect *tcon)
+{
+ /*
+ * Checking waitqueue to releasing tree connect on
+ * tree disconnect. waitqueue_active is safe because it
+ * uses atomic operation for condition.
+ */
+ if (!atomic_dec_return(&tcon->refcount) &&
+ waitqueue_active(&tcon->refcount_q))
+ wake_up(&tcon->refcount_q);
+}
+
int ksmbd_tree_conn_disconnect(struct ksmbd_session *sess,
struct ksmbd_tree_connect *tree_conn)
{
int ret;
+ write_lock(&sess->tree_conns_lock);
+ xa_erase(&sess->tree_conns, tree_conn->id);
+ write_unlock(&sess->tree_conns_lock);
+
+ if (!atomic_dec_and_test(&tree_conn->refcount))
+ wait_event(tree_conn->refcount_q,
+ atomic_read(&tree_conn->refcount) == 0);
+
ret = ksmbd_ipc_tree_disconnect_request(sess->id, tree_conn->id);
ksmbd_release_tree_conn_id(sess, tree_conn->id);
- xa_erase(&sess->tree_conns, tree_conn->id);
ksmbd_share_config_put(tree_conn->share_conf);
kfree(tree_conn);
return ret;
@@ -111,11 +133,15 @@ struct ksmbd_tree_connect *ksmbd_tree_conn_lookup(struct ksmbd_session *sess,
{
struct ksmbd_tree_connect *tcon;
+ read_lock(&sess->tree_conns_lock);
tcon = xa_load(&sess->tree_conns, id);
if (tcon) {
- if (test_bit(TREE_CONN_EXPIRE, &tcon->status))
+ if (tcon->t_state != TREE_CONNECTED)
+ tcon = NULL;
+ else if (!atomic_inc_not_zero(&tcon->refcount))
tcon = NULL;
}
+ read_unlock(&sess->tree_conns_lock);
return tcon;
}
@@ -129,8 +155,18 @@ int ksmbd_tree_conn_session_logoff(struct ksmbd_session *sess)
if (!sess)
return -EINVAL;
- xa_for_each(&sess->tree_conns, id, tc)
+ xa_for_each(&sess->tree_conns, id, tc) {
+ write_lock(&sess->tree_conns_lock);
+ if (tc->t_state == TREE_DISCONNECTED) {
+ write_unlock(&sess->tree_conns_lock);
+ ret = -ENOENT;
+ continue;
+ }
+ tc->t_state = TREE_DISCONNECTED;
+ write_unlock(&sess->tree_conns_lock);
+
ret |= ksmbd_tree_conn_disconnect(sess, tc);
+ }
xa_destroy(&sess->tree_conns);
return ret;
}
diff --git a/fs/smb/server/mgmt/tree_connect.h b/fs/smb/server/mgmt/tree_connect.h
index 562d647..6377a70 100644
--- a/fs/smb/server/mgmt/tree_connect.h
+++ b/fs/smb/server/mgmt/tree_connect.h
@@ -14,7 +14,11 @@ struct ksmbd_share_config;
struct ksmbd_user;
struct ksmbd_conn;
-#define TREE_CONN_EXPIRE 1
+enum {
+ TREE_NEW = 0,
+ TREE_CONNECTED,
+ TREE_DISCONNECTED
+};
struct ksmbd_tree_connect {
int id;
@@ -27,7 +31,9 @@ struct ksmbd_tree_connect {
int maximal_access;
bool posix_extensions;
- unsigned long status;
+ atomic_t refcount;
+ wait_queue_head_t refcount_q;
+ unsigned int t_state;
};
struct ksmbd_tree_conn_status {
@@ -46,6 +52,7 @@ struct ksmbd_session;
struct ksmbd_tree_conn_status
ksmbd_tree_conn_connect(struct ksmbd_conn *conn, struct ksmbd_session *sess,
const char *share_name);
+void ksmbd_tree_connect_put(struct ksmbd_tree_connect *tcon);
int ksmbd_tree_conn_disconnect(struct ksmbd_session *sess,
struct ksmbd_tree_connect *tree_conn);
diff --git a/fs/smb/server/mgmt/user_session.c b/fs/smb/server/mgmt/user_session.c
index 8a5dcab..15f68ee 100644
--- a/fs/smb/server/mgmt/user_session.c
+++ b/fs/smb/server/mgmt/user_session.c
@@ -174,7 +174,7 @@ static void ksmbd_expire_session(struct ksmbd_conn *conn)
unsigned long id;
struct ksmbd_session *sess;
- down_write(&sessions_table_lock);
+ down_write(&conn->session_lock);
xa_for_each(&conn->sessions, id, sess) {
if (sess->state != SMB2_SESSION_VALID ||
time_after(jiffies,
@@ -185,7 +185,7 @@ static void ksmbd_expire_session(struct ksmbd_conn *conn)
continue;
}
}
- up_write(&sessions_table_lock);
+ up_write(&conn->session_lock);
}
int ksmbd_session_register(struct ksmbd_conn *conn,
@@ -227,7 +227,9 @@ void ksmbd_sessions_deregister(struct ksmbd_conn *conn)
}
}
}
+ up_write(&sessions_table_lock);
+ down_write(&conn->session_lock);
xa_for_each(&conn->sessions, id, sess) {
unsigned long chann_id;
struct channel *chann;
@@ -244,7 +246,7 @@ void ksmbd_sessions_deregister(struct ksmbd_conn *conn)
ksmbd_session_destroy(sess);
}
}
- up_write(&sessions_table_lock);
+ up_write(&conn->session_lock);
}
struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn,
@@ -252,9 +254,11 @@ struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn,
{
struct ksmbd_session *sess;
+ down_read(&conn->session_lock);
sess = xa_load(&conn->sessions, id);
if (sess)
sess->last_active = jiffies;
+ up_read(&conn->session_lock);
return sess;
}
@@ -351,6 +355,7 @@ static struct ksmbd_session *__session_create(int protocol)
xa_init(&sess->ksmbd_chann_list);
xa_init(&sess->rpc_handle_list);
sess->sequence_number = 1;
+ rwlock_init(&sess->tree_conns_lock);
ret = __init_smb2_session(sess);
if (ret)
diff --git a/fs/smb/server/mgmt/user_session.h b/fs/smb/server/mgmt/user_session.h
index f99d475..63cb08ff 100644
--- a/fs/smb/server/mgmt/user_session.h
+++ b/fs/smb/server/mgmt/user_session.h
@@ -60,6 +60,7 @@ struct ksmbd_session {
struct ksmbd_file_table file_table;
unsigned long last_active;
+ rwlock_t tree_conns_lock;
};
static inline int test_session_flag(struct ksmbd_session *sess, int bit)
diff --git a/fs/smb/server/server.c b/fs/smb/server/server.c
index 32347fe..3079e60 100644
--- a/fs/smb/server/server.c
+++ b/fs/smb/server/server.c
@@ -241,6 +241,8 @@ static void __handle_ksmbd_work(struct ksmbd_work *work,
} while (is_chained == true);
send:
+ if (work->tcon)
+ ksmbd_tree_connect_put(work->tcon);
smb3_preauth_hash_rsp(work);
if (work->sess && work->sess->enc && work->encrypted &&
conn->ops->encrypt_resp) {
diff --git a/fs/smb/server/smb2pdu.c b/fs/smb/server/smb2pdu.c
index 544022d..898860a 100644
--- a/fs/smb/server/smb2pdu.c
+++ b/fs/smb/server/smb2pdu.c
@@ -1993,6 +1993,9 @@ int smb2_tree_connect(struct ksmbd_work *work)
if (conn->posix_ext_supported)
status.tree_conn->posix_extensions = true;
+ write_lock(&sess->tree_conns_lock);
+ status.tree_conn->t_state = TREE_CONNECTED;
+ write_unlock(&sess->tree_conns_lock);
rsp->StructureSize = cpu_to_le16(16);
out_err1:
rsp->Capabilities = 0;
@@ -2122,27 +2125,50 @@ int smb2_tree_disconnect(struct ksmbd_work *work)
ksmbd_debug(SMB, "request\n");
+ if (!tcon) {
+ ksmbd_debug(SMB, "Invalid tid %d\n", req->hdr.Id.SyncId.TreeId);
+
+ rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED;
+ err = -ENOENT;
+ goto err_out;
+ }
+
+ ksmbd_close_tree_conn_fds(work);
+
+ write_lock(&sess->tree_conns_lock);
+ if (tcon->t_state == TREE_DISCONNECTED) {
+ write_unlock(&sess->tree_conns_lock);
+ rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED;
+ err = -ENOENT;
+ goto err_out;
+ }
+
+ WARN_ON_ONCE(atomic_dec_and_test(&tcon->refcount));
+ tcon->t_state = TREE_DISCONNECTED;
+ write_unlock(&sess->tree_conns_lock);
+
+ err = ksmbd_tree_conn_disconnect(sess, tcon);
+ if (err) {
+ rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED;
+ goto err_out;
+ }
+
+ work->tcon = NULL;
+
rsp->StructureSize = cpu_to_le16(4);
err = ksmbd_iov_pin_rsp(work, rsp,
sizeof(struct smb2_tree_disconnect_rsp));
if (err) {
rsp->hdr.Status = STATUS_INSUFFICIENT_RESOURCES;
- smb2_set_err_rsp(work);
- return err;
+ goto err_out;
}
- if (!tcon || test_and_set_bit(TREE_CONN_EXPIRE, &tcon->status)) {
- ksmbd_debug(SMB, "Invalid tid %d\n", req->hdr.Id.SyncId.TreeId);
-
- rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED;
- smb2_set_err_rsp(work);
- return -ENOENT;
- }
-
- ksmbd_close_tree_conn_fds(work);
- ksmbd_tree_conn_disconnect(sess, tcon);
- work->tcon = NULL;
return 0;
+
+err_out:
+ smb2_set_err_rsp(work);
+ return err;
+
}
/**
@@ -2164,17 +2190,17 @@ int smb2_session_logoff(struct ksmbd_work *work)
ksmbd_debug(SMB, "request\n");
- sess_id = le64_to_cpu(req->hdr.SessionId);
-
- rsp->StructureSize = cpu_to_le16(4);
- err = ksmbd_iov_pin_rsp(work, rsp, sizeof(struct smb2_logoff_rsp));
- if (err) {
- rsp->hdr.Status = STATUS_INSUFFICIENT_RESOURCES;
+ ksmbd_conn_lock(conn);
+ if (!ksmbd_conn_good(conn)) {
+ ksmbd_conn_unlock(conn);
+ rsp->hdr.Status = STATUS_NETWORK_NAME_DELETED;
smb2_set_err_rsp(work);
- return err;
+ return -ENOENT;
}
-
+ sess_id = le64_to_cpu(req->hdr.SessionId);
ksmbd_all_conn_set_status(sess_id, KSMBD_SESS_NEED_RECONNECT);
+ ksmbd_conn_unlock(conn);
+
ksmbd_close_session_fds(work);
ksmbd_conn_wait_idle(conn, sess_id);
@@ -2196,6 +2222,14 @@ int smb2_session_logoff(struct ksmbd_work *work)
ksmbd_free_user(sess->user);
sess->user = NULL;
ksmbd_all_conn_set_status(sess_id, KSMBD_SESS_NEED_NEGOTIATE);
+
+ rsp->StructureSize = cpu_to_le16(4);
+ err = ksmbd_iov_pin_rsp(work, rsp, sizeof(struct smb2_logoff_rsp));
+ if (err) {
+ rsp->hdr.Status = STATUS_INSUFFICIENT_RESOURCES;
+ smb2_set_err_rsp(work);
+ return err;
+ }
return 0;
}
@@ -3370,8 +3404,10 @@ int smb2_open(struct ksmbd_work *work)
}
ksmbd_revert_fsids(work);
err_out1:
- if (!rc)
+ if (!rc) {
+ ksmbd_update_fstate(&work->sess->file_table, fp, FP_INITED);
rc = ksmbd_iov_pin_rsp(work, (void *)rsp, iov_len);
+ }
if (rc) {
if (rc == -EINVAL)
rsp->hdr.Status = STATUS_INVALID_PARAMETER;
@@ -7028,10 +7064,6 @@ int smb2_lock(struct ksmbd_work *work)
ksmbd_debug(SMB,
"would have to wait for getting lock\n");
- spin_lock(&work->conn->llist_lock);
- list_add_tail(&smb_lock->clist,
- &work->conn->lock_list);
- spin_unlock(&work->conn->llist_lock);
list_add(&smb_lock->llist, &rollback_list);
argv = kmalloc(sizeof(void *), GFP_KERNEL);
@@ -7062,9 +7094,6 @@ int smb2_lock(struct ksmbd_work *work)
if (work->state != KSMBD_WORK_ACTIVE) {
list_del(&smb_lock->llist);
- spin_lock(&work->conn->llist_lock);
- list_del(&smb_lock->clist);
- spin_unlock(&work->conn->llist_lock);
locks_free_lock(flock);
if (work->state == KSMBD_WORK_CANCELLED) {
@@ -7084,19 +7113,16 @@ int smb2_lock(struct ksmbd_work *work)
}
list_del(&smb_lock->llist);
- spin_lock(&work->conn->llist_lock);
- list_del(&smb_lock->clist);
- spin_unlock(&work->conn->llist_lock);
release_async_work(work);
goto retry;
} else if (!rc) {
+ list_add(&smb_lock->llist, &rollback_list);
spin_lock(&work->conn->llist_lock);
list_add_tail(&smb_lock->clist,
&work->conn->lock_list);
list_add_tail(&smb_lock->flist,
&fp->lock_list);
spin_unlock(&work->conn->llist_lock);
- list_add(&smb_lock->llist, &rollback_list);
ksmbd_debug(SMB, "successful in taking lock\n");
} else {
goto out;
@@ -8036,10 +8062,10 @@ static void smb20_oplock_break_ack(struct ksmbd_work *work)
goto err_out;
}
- opinfo_put(opinfo);
- ksmbd_fd_put(work, fp);
opinfo->op_state = OPLOCK_STATE_NONE;
wake_up_interruptible_all(&opinfo->oplock_q);
+ opinfo_put(opinfo);
+ ksmbd_fd_put(work, fp);
rsp->StructureSize = cpu_to_le16(24);
rsp->OplockLevel = rsp_oplevel;
diff --git a/fs/smb/server/vfs_cache.c b/fs/smb/server/vfs_cache.c
index f41f8d6..c4b80ab 100644
--- a/fs/smb/server/vfs_cache.c
+++ b/fs/smb/server/vfs_cache.c
@@ -333,6 +333,9 @@ static void __ksmbd_close_fd(struct ksmbd_file_table *ft, struct ksmbd_file *fp)
static struct ksmbd_file *ksmbd_fp_get(struct ksmbd_file *fp)
{
+ if (fp->f_state != FP_INITED)
+ return NULL;
+
if (!atomic_inc_not_zero(&fp->refcount))
return NULL;
return fp;
@@ -382,15 +385,20 @@ int ksmbd_close_fd(struct ksmbd_work *work, u64 id)
return 0;
ft = &work->sess->file_table;
- read_lock(&ft->lock);
+ write_lock(&ft->lock);
fp = idr_find(ft->idr, id);
if (fp) {
set_close_state_blocked_works(fp);
- if (!atomic_dec_and_test(&fp->refcount))
+ if (fp->f_state != FP_INITED)
fp = NULL;
+ else {
+ fp->f_state = FP_CLOSED;
+ if (!atomic_dec_and_test(&fp->refcount))
+ fp = NULL;
+ }
}
- read_unlock(&ft->lock);
+ write_unlock(&ft->lock);
if (!fp)
return -EINVAL;
@@ -570,6 +578,7 @@ struct ksmbd_file *ksmbd_open_fd(struct ksmbd_work *work, struct file *filp)
fp->tcon = work->tcon;
fp->volatile_id = KSMBD_NO_FID;
fp->persistent_id = KSMBD_NO_FID;
+ fp->f_state = FP_NEW;
fp->f_ci = ksmbd_inode_get(fp);
if (!fp->f_ci) {
@@ -591,6 +600,14 @@ struct ksmbd_file *ksmbd_open_fd(struct ksmbd_work *work, struct file *filp)
return ERR_PTR(ret);
}
+void ksmbd_update_fstate(struct ksmbd_file_table *ft, struct ksmbd_file *fp,
+ unsigned int state)
+{
+ write_lock(&ft->lock);
+ fp->f_state = state;
+ write_unlock(&ft->lock);
+}
+
static int
__close_file_table_ids(struct ksmbd_file_table *ft,
struct ksmbd_tree_connect *tcon,
diff --git a/fs/smb/server/vfs_cache.h b/fs/smb/server/vfs_cache.h
index fcb1341..03d0bf9 100644
--- a/fs/smb/server/vfs_cache.h
+++ b/fs/smb/server/vfs_cache.h
@@ -60,6 +60,12 @@ struct ksmbd_inode {
__le32 m_fattr;
};
+enum {
+ FP_NEW = 0,
+ FP_INITED,
+ FP_CLOSED
+};
+
struct ksmbd_file {
struct file *filp;
u64 persistent_id;
@@ -98,6 +104,7 @@ struct ksmbd_file {
/* if ls is happening on directory, below is valid*/
struct ksmbd_readdir_data readdir_data;
int dot_dotdot[2];
+ unsigned int f_state;
};
static inline void set_ctx_actor(struct dir_context *ctx,
@@ -142,6 +149,8 @@ int ksmbd_close_inode_fds(struct ksmbd_work *work, struct inode *inode);
int ksmbd_init_global_file_table(void);
void ksmbd_free_global_file_table(void);
void ksmbd_set_fd_limit(unsigned long limit);
+void ksmbd_update_fstate(struct ksmbd_file_table *ft, struct ksmbd_file *fp,
+ unsigned int state);
/*
* INODE hash
