[PATCH 4.19 076/120] net: decnet: Fix sleeping inside in af_decnet

Greg Kroah-Hartman
2021-07-26T16:05:53Z

From: Yajun Deng <yajun.deng@linux.dev>

[ Upstream commit 5f119ba1d5771bbf46d57cff7417dcd84d3084ba ]

The release_sock() is blocking function, it would change the state
after sleeping. use wait_woken() instead.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Yajun Deng <yajun.deng@linux.dev>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
net/decnet/af_decnet.c | 27 ++++++++++++---------------
1 file changed, 12 insertions(+), 15 deletions(-)

diff --git a/net/decnet/af_decnet.c b/net/decnet/af_decnet.c
index 0e6f32defd67..cc7077105969 100644
--- a/net/decnet/af_decnet.c
+++ b/net/decnet/af_decnet.c
@@ -823,7 +823,7 @@ static int dn_auto_bind(struct socket *sock)
static int dn_confirm_accept(struct sock *sk, long *timeo, gfp_t allocation)
{
struct dn_scp *scp = DN_SK(sk);
- DEFINE_WAIT(wait);
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
int err;

if (scp->state != DN_CR)
@@ -833,11 +833,11 @@ static int dn_confirm_accept(struct sock *sk, long *timeo, gfp_t allocation)
scp->segsize_loc = dst_metric_advmss(__sk_dst_get(sk));
dn_send_conn_conf(sk, allocation);

- prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+ add_wait_queue(sk_sleep(sk), &wait);
for(;;) {
release_sock(sk);
if (scp->state == DN_CC)
- *timeo = schedule_timeout(*timeo);
+ *timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, *timeo);
lock_sock(sk);
err = 0;
if (scp->state == DN_RUN)
@@ -851,9 +851,8 @@ static int dn_confirm_accept(struct sock *sk, long *timeo, gfp_t allocation)
err = -EAGAIN;
if (!*timeo)
break;
- prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
}
- finish_wait(sk_sleep(sk), &wait);
+ remove_wait_queue(sk_sleep(sk), &wait);
if (err == 0) {
sk->sk_socket->state = SS_CONNECTED;
} else if (scp->state != DN_CC) {
@@ -865,7 +864,7 @@ static int dn_confirm_accept(struct sock *sk, long *timeo, gfp_t allocation)
static int dn_wait_run(struct sock *sk, long *timeo)
{
struct dn_scp *scp = DN_SK(sk);
- DEFINE_WAIT(wait);
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
int err = 0;

if (scp->state == DN_RUN)
@@ -874,11 +873,11 @@ static int dn_wait_run(struct sock *sk, long *timeo)
if (!*timeo)
return -EALREADY;

- prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+ add_wait_queue(sk_sleep(sk), &wait);
for(;;) {
release_sock(sk);
if (scp->state == DN_CI || scp->state == DN_CC)
- *timeo = schedule_timeout(*timeo);
+ *timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, *timeo);
lock_sock(sk);
err = 0;
if (scp->state == DN_RUN)
@@ -892,9 +891,8 @@ static int dn_wait_run(struct sock *sk, long *timeo)
err = -ETIMEDOUT;
if (!*timeo)
break;
- prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
}
- finish_wait(sk_sleep(sk), &wait);
+ remove_wait_queue(sk_sleep(sk), &wait);
out:
if (err == 0) {
sk->sk_socket->state = SS_CONNECTED;
@@ -1039,16 +1037,16 @@ static void dn_user_copy(struct sk_buff *skb, struct optdata_dn *opt)

static struct sk_buff *dn_wait_for_connect(struct sock *sk, long *timeo)
{
- DEFINE_WAIT(wait);
+ DEFINE_WAIT_FUNC(wait, woken_wake_function);
struct sk_buff *skb = NULL;
int err = 0;

- prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
+ add_wait_queue(sk_sleep(sk), &wait);
for(;;) {
release_sock(sk);
skb = skb_dequeue(&sk->sk_receive_queue);
if (skb == NULL) {
- *timeo = schedule_timeout(*timeo);
+ *timeo = wait_woken(&wait, TASK_INTERRUPTIBLE, *timeo);
skb = skb_dequeue(&sk->sk_receive_queue);
}
lock_sock(sk);
@@ -1063,9 +1061,8 @@ static struct sk_buff *dn_wait_for_connect(struct sock *sk, long *timeo)
err = -EAGAIN;
if (!*timeo)
break;
- prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
}
- finish_wait(sk_sleep(sk), &wait);
+ remove_wait_queue(sk_sleep(sk), &wait);

return skb == NULL ? ERR_PTR(err) : skb;
}
--
2.30.2