From 3abab905b14f4ba756d413f37f1fb02b708eee93 Mon Sep 17 00:00:00 2001 From: Jinjie Ruan Date: Mon, 28 Oct 2024 08:28:30 +0900 Subject: ksmbd: Fix the missing xa_store error check xa_store() can fail, it return xa_err(-EINVAL) if the entry cannot be stored in an XArray, or xa_err(-ENOMEM) if memory allocation failed, so check error for xa_store() to fix it. Cc: stable@vger.kernel.org Fixes: b685757c7b08 ("ksmbd: Implements sess->rpc_handle_list as xarray") Signed-off-by: Jinjie Ruan Acked-by: Namjae Jeon Signed-off-by: Steve French --- fs/smb/server/mgmt/user_session.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/fs/smb/server/mgmt/user_session.c b/fs/smb/server/mgmt/user_session.c index 1e4624e9d434..9756a4bbfe54 100644 --- a/fs/smb/server/mgmt/user_session.c +++ b/fs/smb/server/mgmt/user_session.c @@ -90,7 +90,7 @@ static int __rpc_method(char *rpc_name) int ksmbd_session_rpc_open(struct ksmbd_session *sess, char *rpc_name) { - struct ksmbd_session_rpc *entry; + struct ksmbd_session_rpc *entry, *old; struct ksmbd_rpc_command *resp; int method; @@ -106,16 +106,19 @@ int ksmbd_session_rpc_open(struct ksmbd_session *sess, char *rpc_name) entry->id = ksmbd_ipc_id_alloc(); if (entry->id < 0) goto free_entry; - xa_store(&sess->rpc_handle_list, entry->id, entry, GFP_KERNEL); + old = xa_store(&sess->rpc_handle_list, entry->id, entry, GFP_KERNEL); + if (xa_is_err(old)) + goto free_id; resp = ksmbd_rpc_open(sess, entry->id); if (!resp) - goto free_id; + goto erase_xa; kvfree(resp); return entry->id; -free_id: +erase_xa: xa_erase(&sess->rpc_handle_list, entry->id); +free_id: ksmbd_rpc_id_free(entry->id); free_entry: kfree(entry); -- cgit v1.2.3-70-g09d2 From 0a77715db22611df50b178374c51e2ba0d58866e Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Sat, 2 Nov 2024 18:46:38 +0900 Subject: ksmbd: fix slab-use-after-free in ksmbd_smb2_session_create There is a race condition between ksmbd_smb2_session_create and ksmbd_expire_session. This patch add missing sessions_table_lock while adding/deleting session from global session table. Cc: stable@vger.kernel.org # v5.15+ Reported-by: Norbert Szetei Tested-by: Norbert Szetei Signed-off-by: Namjae Jeon Signed-off-by: Steve French --- fs/smb/server/mgmt/user_session.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/fs/smb/server/mgmt/user_session.c b/fs/smb/server/mgmt/user_session.c index 9756a4bbfe54..ad02fe555fda 100644 --- a/fs/smb/server/mgmt/user_session.c +++ b/fs/smb/server/mgmt/user_session.c @@ -178,6 +178,7 @@ 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 (atomic_read(&sess->refcnt) == 0 && @@ -191,6 +192,7 @@ static void ksmbd_expire_session(struct ksmbd_conn *conn) } } up_write(&conn->session_lock); + up_write(&sessions_table_lock); } int ksmbd_session_register(struct ksmbd_conn *conn, @@ -232,7 +234,6 @@ 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) { @@ -252,6 +253,7 @@ void ksmbd_sessions_deregister(struct ksmbd_conn *conn) } } up_write(&conn->session_lock); + up_write(&sessions_table_lock); } struct ksmbd_session *ksmbd_session_lookup(struct ksmbd_conn *conn, -- cgit v1.2.3-70-g09d2 From b8fc56fbca7482c1e5c0e3351c6ae78982e25ada Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Mon, 4 Nov 2024 13:40:41 +0900 Subject: ksmbd: fix slab-use-after-free in smb3_preauth_hash_rsp ksmbd_user_session_put should be called under smb3_preauth_hash_rsp(). It will avoid freeing session before calling smb3_preauth_hash_rsp(). Cc: stable@vger.kernel.org # v5.15+ Reported-by: Norbert Szetei Tested-by: Norbert Szetei Signed-off-by: Namjae Jeon Signed-off-by: Steve French --- fs/smb/server/server.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/fs/smb/server/server.c b/fs/smb/server/server.c index 9670c97f14b3..e7f14f8df943 100644 --- a/fs/smb/server/server.c +++ b/fs/smb/server/server.c @@ -238,11 +238,11 @@ static void __handle_ksmbd_work(struct ksmbd_work *work, } while (is_chained == true); send: - if (work->sess) - ksmbd_user_session_put(work->sess); if (work->tcon) ksmbd_tree_connect_put(work->tcon); smb3_preauth_hash_rsp(work); + if (work->sess) + ksmbd_user_session_put(work->sess); if (work->sess && work->sess->enc && work->encrypted && conn->ops->encrypt_resp) { rc = conn->ops->encrypt_resp(work); -- cgit v1.2.3-70-g09d2 From 0a77d947f599b1f39065015bec99390d0c0022ee Mon Sep 17 00:00:00 2001 From: Namjae Jeon Date: Mon, 4 Nov 2024 13:43:06 +0900 Subject: ksmbd: check outstanding simultaneous SMB operations MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit If Client send simultaneous SMB operations to ksmbd, It exhausts too much memory through the "ksmbd_work_cache”. It will cause OOM issue. ksmbd has a credit mechanism but it can't handle this problem. This patch add the check if it exceeds max credits to prevent this problem by assuming that one smb request consumes at least one credit. Cc: stable@vger.kernel.org # v5.15+ Reported-by: Norbert Szetei Tested-by: Norbert Szetei Signed-off-by: Namjae Jeon Signed-off-by: Steve French --- fs/smb/server/connection.c | 1 + fs/smb/server/connection.h | 1 + fs/smb/server/server.c | 16 ++++++++++------ fs/smb/server/smb_common.c | 10 +++++++--- fs/smb/server/smb_common.h | 2 +- 5 files changed, 20 insertions(+), 10 deletions(-) diff --git a/fs/smb/server/connection.c b/fs/smb/server/connection.c index aa2a37a7ce84..e6a72f75ab94 100644 --- a/fs/smb/server/connection.c +++ b/fs/smb/server/connection.c @@ -70,6 +70,7 @@ struct ksmbd_conn *ksmbd_conn_alloc(void) atomic_set(&conn->req_running, 0); atomic_set(&conn->r_count, 0); atomic_set(&conn->refcnt, 1); + atomic_set(&conn->mux_smb_requests, 0); conn->total_credits = 1; conn->outstanding_credits = 0; diff --git a/fs/smb/server/connection.h b/fs/smb/server/connection.h index b379ae4fdcdf..8ddd5a3c7baf 100644 --- a/fs/smb/server/connection.h +++ b/fs/smb/server/connection.h @@ -107,6 +107,7 @@ struct ksmbd_conn { __le16 signing_algorithm; bool binding; atomic_t refcnt; + atomic_t mux_smb_requests; }; struct ksmbd_conn_ops { diff --git a/fs/smb/server/server.c b/fs/smb/server/server.c index e7f14f8df943..e6cfedba9992 100644 --- a/fs/smb/server/server.c +++ b/fs/smb/server/server.c @@ -270,6 +270,7 @@ static void handle_ksmbd_work(struct work_struct *wk) ksmbd_conn_try_dequeue_request(work); ksmbd_free_work_struct(work); + atomic_dec(&conn->mux_smb_requests); /* * Checking waitqueue to dropping pending requests on * disconnection. waitqueue_active is safe because it @@ -291,6 +292,15 @@ static int queue_ksmbd_work(struct ksmbd_conn *conn) struct ksmbd_work *work; int err; + err = ksmbd_init_smb_server(conn); + if (err) + return 0; + + if (atomic_inc_return(&conn->mux_smb_requests) >= conn->vals->max_credits) { + atomic_dec_return(&conn->mux_smb_requests); + return -ENOSPC; + } + work = ksmbd_alloc_work_struct(); if (!work) { pr_err("allocation for work failed\n"); @@ -301,12 +311,6 @@ static int queue_ksmbd_work(struct ksmbd_conn *conn) work->request_buf = conn->request_buf; conn->request_buf = NULL; - err = ksmbd_init_smb_server(work); - if (err) { - ksmbd_free_work_struct(work); - return 0; - } - ksmbd_conn_enqueue_request(work); atomic_inc(&conn->r_count); /* update activity on connection */ diff --git a/fs/smb/server/smb_common.c b/fs/smb/server/smb_common.c index a2ebbe604c8c..75b4eb856d32 100644 --- a/fs/smb/server/smb_common.c +++ b/fs/smb/server/smb_common.c @@ -388,6 +388,10 @@ static struct smb_version_ops smb1_server_ops = { .set_rsp_status = set_smb1_rsp_status, }; +static struct smb_version_values smb1_server_values = { + .max_credits = SMB2_MAX_CREDITS, +}; + static int smb1_negotiate(struct ksmbd_work *work) { return ksmbd_smb_negotiate_common(work, SMB_COM_NEGOTIATE); @@ -399,18 +403,18 @@ static struct smb_version_cmds smb1_server_cmds[1] = { static int init_smb1_server(struct ksmbd_conn *conn) { + conn->vals = &smb1_server_values; conn->ops = &smb1_server_ops; conn->cmds = smb1_server_cmds; conn->max_cmds = ARRAY_SIZE(smb1_server_cmds); return 0; } -int ksmbd_init_smb_server(struct ksmbd_work *work) +int ksmbd_init_smb_server(struct ksmbd_conn *conn) { - struct ksmbd_conn *conn = work->conn; __le32 proto; - proto = *(__le32 *)((struct smb_hdr *)work->request_buf)->Protocol; + proto = *(__le32 *)((struct smb_hdr *)conn->request_buf)->Protocol; if (conn->need_neg == false) { if (proto == SMB1_PROTO_NUMBER) return -EINVAL; diff --git a/fs/smb/server/smb_common.h b/fs/smb/server/smb_common.h index cc1d6dfe29d5..a3d8a905b07e 100644 --- a/fs/smb/server/smb_common.h +++ b/fs/smb/server/smb_common.h @@ -427,7 +427,7 @@ bool ksmbd_smb_request(struct ksmbd_conn *conn); int ksmbd_lookup_dialect_by_id(__le16 *cli_dialects, __le16 dialects_count); -int ksmbd_init_smb_server(struct ksmbd_work *work); +int ksmbd_init_smb_server(struct ksmbd_conn *conn); struct ksmbd_kstat; int ksmbd_populate_dot_dotdot_entries(struct ksmbd_work *work, -- cgit v1.2.3-70-g09d2