This is a note to let you know that I've just added the patch titled
ksmbd: fix slab-out-of-bounds in init_smb2_rsp_hdr
to the 6.2-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
ksmbd-fix-slab-out-of-bounds-in-init_smb2_rsp_hdr.patch
and it can be found in the queue-6.2 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From dc8289f912387c3bcfbc5d2db29c8947fa207c11 Mon Sep 17 00:00:00 2001
From: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Date: Sat, 1 Apr 2023 13:21:04 +0900
Subject: ksmbd: fix slab-out-of-bounds in init_smb2_rsp_hdr
From: Namjae Jeon <linkinjeon@xxxxxxxxxx>
commit dc8289f912387c3bcfbc5d2db29c8947fa207c11 upstream.
When smb1 mount fails, KASAN detect slab-out-of-bounds in
init_smb2_rsp_hdr like the following one.
For smb1 negotiate(56bytes) , init_smb2_rsp_hdr() for smb2 is called.
The issue occurs while handling smb1 negotiate as smb2 server operations.
Add smb server operations for smb1 (get_cmd_val, init_rsp_hdr,
allocate_rsp_buf, check_user_session) to handle smb1 negotiate so that
smb2 server operation does not handle it.
[ 411.400423] CIFS: VFS: Use of the less secure dialect vers=1.0 is
not recommended unless required for access to very old servers
[ 411.400452] CIFS: Attempting to mount \\192.168.45.139\homes
[ 411.479312] ksmbd: init_smb2_rsp_hdr : 492
[ 411.479323] ==================================================================
[ 411.479327] BUG: KASAN: slab-out-of-bounds in
init_smb2_rsp_hdr+0x1e2/0x1f4 [ksmbd]
[ 411.479369] Read of size 16 at addr ffff888488ed0734 by task kworker/14:1/199
[ 411.479379] CPU: 14 PID: 199 Comm: kworker/14:1 Tainted: G
OE 6.1.21 #3
[ 411.479386] Hardware name: ASUSTeK COMPUTER INC. Z10PA-D8
Series/Z10PA-D8 Series, BIOS 3801 08/23/2019
[ 411.479390] Workqueue: ksmbd-io handle_ksmbd_work [ksmbd]
[ 411.479425] Call Trace:
[ 411.479428] <TASK>
[ 411.479432] dump_stack_lvl+0x49/0x63
[ 411.479444] print_report+0x171/0x4a8
[ 411.479452] ? kasan_complete_mode_report_info+0x3c/0x200
[ 411.479463] ? init_smb2_rsp_hdr+0x1e2/0x1f4 [ksmbd]
[ 411.479497] kasan_report+0xb4/0x130
[ 411.479503] ? init_smb2_rsp_hdr+0x1e2/0x1f4 [ksmbd]
[ 411.479537] kasan_check_range+0x149/0x1e0
[ 411.479543] memcpy+0x24/0x70
[ 411.479550] init_smb2_rsp_hdr+0x1e2/0x1f4 [ksmbd]
[ 411.479585] handle_ksmbd_work+0x109/0x760 [ksmbd]
[ 411.479616] ? _raw_spin_unlock_irqrestore+0x50/0x50
[ 411.479624] ? smb3_encrypt_resp+0x340/0x340 [ksmbd]
[ 411.479656] process_one_work+0x49c/0x790
[ 411.479667] worker_thread+0x2b1/0x6e0
[ 411.479674] ? process_one_work+0x790/0x790
[ 411.479680] kthread+0x177/0x1b0
[ 411.479686] ? kthread_complete_and_exit+0x30/0x30
[ 411.479692] ret_from_fork+0x22/0x30
[ 411.479702] </TASK>
Fixes: 39b291b86b59 ("ksmbd: return unsupported error on smb1 mount")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Signed-off-by: Steve French <stfrench@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/ksmbd/server.c | 5 -
fs/ksmbd/smb2pdu.c | 3 -
fs/ksmbd/smb_common.c | 138 +++++++++++++++++++++++++++++++++++++++-----------
fs/ksmbd/smb_common.h | 2
4 files changed, 111 insertions(+), 37 deletions(-)
--- a/fs/ksmbd/server.c
+++ b/fs/ksmbd/server.c
@@ -289,10 +289,7 @@ static int queue_ksmbd_work(struct ksmbd
work->request_buf = conn->request_buf;
conn->request_buf = NULL;
- if (ksmbd_init_smb_server(work)) {
- ksmbd_free_work_struct(work);
- return -EINVAL;
- }
+ ksmbd_init_smb_server(work);
ksmbd_conn_enqueue_request(work);
atomic_inc(&conn->r_count);
--- a/fs/ksmbd/smb2pdu.c
+++ b/fs/ksmbd/smb2pdu.c
@@ -235,9 +235,6 @@ int init_smb2_neg_rsp(struct ksmbd_work
struct smb2_negotiate_rsp *rsp;
struct ksmbd_conn *conn = work->conn;
- if (conn->need_neg == false)
- return -EINVAL;
-
*(__be32 *)work->response_buf =
cpu_to_be32(conn->vals->header_size);
--- a/fs/ksmbd/smb_common.c
+++ b/fs/ksmbd/smb_common.c
@@ -283,20 +283,121 @@ err_out:
return BAD_PROT_ID;
}
-int ksmbd_init_smb_server(struct ksmbd_work *work)
+#define SMB_COM_NEGOTIATE_EX 0x0
+
+/**
+ * get_smb1_cmd_val() - get smb command value from smb header
+ * @work: smb work containing smb header
+ *
+ * Return: smb command value
+ */
+static u16 get_smb1_cmd_val(struct ksmbd_work *work)
{
- struct ksmbd_conn *conn = work->conn;
+ return SMB_COM_NEGOTIATE_EX;
+}
- if (conn->need_neg == false)
+/**
+ * init_smb1_rsp_hdr() - initialize smb negotiate response header
+ * @work: smb work containing smb request
+ *
+ * Return: 0 on success, otherwise -EINVAL
+ */
+static int init_smb1_rsp_hdr(struct ksmbd_work *work)
+{
+ struct smb_hdr *rsp_hdr = (struct smb_hdr *)work->response_buf;
+ struct smb_hdr *rcv_hdr = (struct smb_hdr *)work->request_buf;
+
+ /*
+ * Remove 4 byte direct TCP header.
+ */
+ *(__be32 *)work->response_buf =
+ cpu_to_be32(sizeof(struct smb_hdr) - 4);
+
+ rsp_hdr->Command = SMB_COM_NEGOTIATE;
+ *(__le32 *)rsp_hdr->Protocol = SMB1_PROTO_NUMBER;
+ rsp_hdr->Flags = SMBFLG_RESPONSE;
+ rsp_hdr->Flags2 = SMBFLG2_UNICODE | SMBFLG2_ERR_STATUS |
+ SMBFLG2_EXT_SEC | SMBFLG2_IS_LONG_NAME;
+ rsp_hdr->Pid = rcv_hdr->Pid;
+ rsp_hdr->Mid = rcv_hdr->Mid;
+ return 0;
+}
+
+/**
+ * smb1_check_user_session() - check for valid session for a user
+ * @work: smb work containing smb request buffer
+ *
+ * Return: 0 on success, otherwise error
+ */
+static int smb1_check_user_session(struct ksmbd_work *work)
+{
+ unsigned int cmd = work->conn->ops->get_cmd_val(work);
+
+ if (cmd == SMB_COM_NEGOTIATE_EX)
return 0;
- init_smb3_11_server(conn);
+ return -EINVAL;
+}
+
+/**
+ * smb1_allocate_rsp_buf() - allocate response buffer for a command
+ * @work: smb work containing smb request
+ *
+ * Return: 0 on success, otherwise -ENOMEM
+ */
+static int smb1_allocate_rsp_buf(struct ksmbd_work *work)
+{
+ work->response_buf = kmalloc(MAX_CIFS_SMALL_BUFFER_SIZE,
+ GFP_KERNEL | __GFP_ZERO);
+ work->response_sz = MAX_CIFS_SMALL_BUFFER_SIZE;
+
+ if (!work->response_buf) {
+ pr_err("Failed to allocate %u bytes buffer\n",
+ MAX_CIFS_SMALL_BUFFER_SIZE);
+ return -ENOMEM;
+ }
- if (conn->ops->get_cmd_val(work) != SMB_COM_NEGOTIATE)
- conn->need_neg = false;
return 0;
}
+static struct smb_version_ops smb1_server_ops = {
+ .get_cmd_val = get_smb1_cmd_val,
+ .init_rsp_hdr = init_smb1_rsp_hdr,
+ .allocate_rsp_buf = smb1_allocate_rsp_buf,
+ .check_user_session = smb1_check_user_session,
+};
+
+static int smb1_negotiate(struct ksmbd_work *work)
+{
+ return ksmbd_smb_negotiate_common(work, SMB_COM_NEGOTIATE);
+}
+
+static struct smb_version_cmds smb1_server_cmds[1] = {
+ [SMB_COM_NEGOTIATE_EX] = { .proc = smb1_negotiate, },
+};
+
+static void init_smb1_server(struct ksmbd_conn *conn)
+{
+ conn->ops = &smb1_server_ops;
+ conn->cmds = smb1_server_cmds;
+ conn->max_cmds = ARRAY_SIZE(smb1_server_cmds);
+}
+
+void ksmbd_init_smb_server(struct ksmbd_work *work)
+{
+ struct ksmbd_conn *conn = work->conn;
+ __le32 proto;
+
+ if (conn->need_neg == false)
+ return;
+
+ proto = *(__le32 *)((struct smb_hdr *)work->request_buf)->Protocol;
+ if (proto == SMB1_PROTO_NUMBER)
+ init_smb1_server(conn);
+ else
+ init_smb3_11_server(conn);
+}
+
int ksmbd_populate_dot_dotdot_entries(struct ksmbd_work *work, int info_level,
struct ksmbd_file *dir,
struct ksmbd_dir_info *d_info,
@@ -444,20 +545,10 @@ static int smb_handle_negotiate(struct k
ksmbd_debug(SMB, "Unsupported SMB1 protocol\n");
- /*
- * Remove 4 byte direct TCP header, add 2 byte bcc and
- * 2 byte DialectIndex.
- */
- *(__be32 *)work->response_buf =
- cpu_to_be32(sizeof(struct smb_hdr) - 4 + 2 + 2);
+ /* Add 2 byte bcc and 2 byte DialectIndex. */
+ inc_rfc1001_len(work->response_buf, 4);
neg_rsp->hdr.Status.CifsError = STATUS_SUCCESS;
- neg_rsp->hdr.Command = SMB_COM_NEGOTIATE;
- *(__le32 *)neg_rsp->hdr.Protocol = SMB1_PROTO_NUMBER;
- neg_rsp->hdr.Flags = SMBFLG_RESPONSE;
- neg_rsp->hdr.Flags2 = SMBFLG2_UNICODE | SMBFLG2_ERR_STATUS |
- SMBFLG2_EXT_SEC | SMBFLG2_IS_LONG_NAME;
-
neg_rsp->hdr.WordCount = 1;
neg_rsp->DialectIndex = cpu_to_le16(work->conn->dialect);
neg_rsp->ByteCount = 0;
@@ -474,23 +565,12 @@ int ksmbd_smb_negotiate_common(struct ks
ksmbd_debug(SMB, "conn->dialect 0x%x\n", conn->dialect);
if (command == SMB2_NEGOTIATE_HE) {
- struct smb2_hdr *smb2_hdr = smb2_get_msg(work->request_buf);
-
- if (smb2_hdr->ProtocolId != SMB2_PROTO_NUMBER) {
- ksmbd_debug(SMB, "Downgrade to SMB1 negotiation\n");
- command = SMB_COM_NEGOTIATE;
- }
- }
-
- if (command == SMB2_NEGOTIATE_HE) {
ret = smb2_handle_negotiate(work);
- init_smb2_neg_rsp(work);
return ret;
}
if (command == SMB_COM_NEGOTIATE) {
if (__smb2_negotiate(conn)) {
- conn->need_neg = true;
init_smb3_11_server(conn);
init_smb2_neg_rsp(work);
ksmbd_debug(SMB, "Upgrade to SMB2 negotiation\n");
--- a/fs/ksmbd/smb_common.h
+++ b/fs/ksmbd/smb_common.h
@@ -427,7 +427,7 @@ bool ksmbd_smb_request(struct ksmbd_conn
int ksmbd_lookup_dialect_by_id(__le16 *cli_dialects, __le16 dialects_count);
-int ksmbd_init_smb_server(struct ksmbd_work *work);
+void ksmbd_init_smb_server(struct ksmbd_work *work);
struct ksmbd_kstat;
int ksmbd_populate_dot_dotdot_entries(struct ksmbd_work *work,
Patches currently in stable-queue which might be from linkinjeon@xxxxxxxxxx are
queue-6.2/ksmbd-do-not-call-kvmalloc-with-__gfp_noretry-__gfp_no_warn.patch
queue-6.2/ksmbd-fix-slab-out-of-bounds-in-init_smb2_rsp_hdr.patch
