[SCSI] iscsi_tcp: fix locking around iscsi sk user data
iscsi_sw_tcp_conn_restore_callbacks could have set the sk_user_data field to NULL then iscsi_sw_tcp_data_ready could read that and try to access the NULL pointer. This adds some checks for NULL sk_user_data in the sk callback functions and it uses the sk_callback_lock to set/get that sk_user_data field. Signed-off-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <JBottomley@Parallels.com>
This commit is contained in:
parent
f457a46f17
commit
03adb5f912
1 changed files with 41 additions and 20 deletions
|
@ -107,10 +107,12 @@ static int iscsi_sw_tcp_recv(read_descriptor_t *rd_desc, struct sk_buff *skb,
|
|||
* If the socket is in CLOSE or CLOSE_WAIT we should
|
||||
* not close the connection if there is still some
|
||||
* data pending.
|
||||
*
|
||||
* Must be called with sk_callback_lock.
|
||||
*/
|
||||
static inline int iscsi_sw_sk_state_check(struct sock *sk)
|
||||
{
|
||||
struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
|
||||
struct iscsi_conn *conn = sk->sk_user_data;
|
||||
|
||||
if ((sk->sk_state == TCP_CLOSE_WAIT || sk->sk_state == TCP_CLOSE) &&
|
||||
!atomic_read(&sk->sk_rmem_alloc)) {
|
||||
|
@ -123,11 +125,17 @@ static inline int iscsi_sw_sk_state_check(struct sock *sk)
|
|||
|
||||
static void iscsi_sw_tcp_data_ready(struct sock *sk, int flag)
|
||||
{
|
||||
struct iscsi_conn *conn = sk->sk_user_data;
|
||||
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
|
||||
struct iscsi_conn *conn;
|
||||
struct iscsi_tcp_conn *tcp_conn;
|
||||
read_descriptor_t rd_desc;
|
||||
|
||||
read_lock(&sk->sk_callback_lock);
|
||||
conn = sk->sk_user_data;
|
||||
if (!conn) {
|
||||
read_unlock(&sk->sk_callback_lock);
|
||||
return;
|
||||
}
|
||||
tcp_conn = conn->dd_data;
|
||||
|
||||
/*
|
||||
* Use rd_desc to pass 'conn' to iscsi_tcp_recv.
|
||||
|
@ -141,11 +149,10 @@ static void iscsi_sw_tcp_data_ready(struct sock *sk, int flag)
|
|||
|
||||
iscsi_sw_sk_state_check(sk);
|
||||
|
||||
read_unlock(&sk->sk_callback_lock);
|
||||
|
||||
/* If we had to (atomically) map a highmem page,
|
||||
* unmap it now. */
|
||||
iscsi_tcp_segment_unmap(&tcp_conn->in.segment);
|
||||
read_unlock(&sk->sk_callback_lock);
|
||||
}
|
||||
|
||||
static void iscsi_sw_tcp_state_change(struct sock *sk)
|
||||
|
@ -157,8 +164,11 @@ static void iscsi_sw_tcp_state_change(struct sock *sk)
|
|||
void (*old_state_change)(struct sock *);
|
||||
|
||||
read_lock(&sk->sk_callback_lock);
|
||||
|
||||
conn = (struct iscsi_conn*)sk->sk_user_data;
|
||||
conn = sk->sk_user_data;
|
||||
if (!conn) {
|
||||
read_unlock(&sk->sk_callback_lock);
|
||||
return;
|
||||
}
|
||||
session = conn->session;
|
||||
|
||||
iscsi_sw_sk_state_check(sk);
|
||||
|
@ -178,11 +188,25 @@ static void iscsi_sw_tcp_state_change(struct sock *sk)
|
|||
**/
|
||||
static void iscsi_sw_tcp_write_space(struct sock *sk)
|
||||
{
|
||||
struct iscsi_conn *conn = (struct iscsi_conn*)sk->sk_user_data;
|
||||
struct iscsi_tcp_conn *tcp_conn = conn->dd_data;
|
||||
struct iscsi_sw_tcp_conn *tcp_sw_conn = tcp_conn->dd_data;
|
||||
struct iscsi_conn *conn;
|
||||
struct iscsi_tcp_conn *tcp_conn;
|
||||
struct iscsi_sw_tcp_conn *tcp_sw_conn;
|
||||
void (*old_write_space)(struct sock *);
|
||||
|
||||
read_lock_bh(&sk->sk_callback_lock);
|
||||
conn = sk->sk_user_data;
|
||||
if (!conn) {
|
||||
read_unlock_bh(&sk->sk_callback_lock);
|
||||
return;
|
||||
}
|
||||
|
||||
tcp_conn = conn->dd_data;
|
||||
tcp_sw_conn = tcp_conn->dd_data;
|
||||
old_write_space = tcp_sw_conn->old_write_space;
|
||||
read_unlock_bh(&sk->sk_callback_lock);
|
||||
|
||||
old_write_space(sk);
|
||||
|
||||
tcp_sw_conn->old_write_space(sk);
|
||||
ISCSI_SW_TCP_DBG(conn, "iscsi_write_space\n");
|
||||
iscsi_conn_queue_work(conn);
|
||||
}
|
||||
|
@ -592,20 +616,17 @@ static void iscsi_sw_tcp_conn_stop(struct iscsi_cls_conn *cls_conn, int flag)
|
|||
/* userspace may have goofed up and not bound us */
|
||||
if (!sock)
|
||||
return;
|
||||
/*
|
||||
* Make sure our recv side is stopped.
|
||||
* Older tools called conn stop before ep_disconnect
|
||||
* so IO could still be coming in.
|
||||
*/
|
||||
write_lock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock);
|
||||
set_bit(ISCSI_SUSPEND_BIT, &conn->suspend_rx);
|
||||
write_unlock_bh(&tcp_sw_conn->sock->sk->sk_callback_lock);
|
||||
|
||||
sock->sk->sk_err = EIO;
|
||||
wake_up_interruptible(sk_sleep(sock->sk));
|
||||
|
||||
iscsi_conn_stop(cls_conn, flag);
|
||||
/* stop xmit side */
|
||||
iscsi_suspend_tx(conn);
|
||||
|
||||
/* stop recv side and release socket */
|
||||
iscsi_sw_tcp_release_conn(conn);
|
||||
|
||||
iscsi_conn_stop(cls_conn, flag);
|
||||
}
|
||||
|
||||
static int
|
||||
|
|
Loading…
Reference in a new issue