crypto: chtls - wait for memory sendmsg, sendpage

address suspicious code <gustavo@embeddedor.com>

1210       set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
1211       }

The issue is that in the code above, set_bit is never reached
due to the 'continue' statement at line 1208.

Also reported by bug report:<dan.carpenter@oracle.com>
1210       set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Not reachable.

Its required to wait for buffer in the send path and takes care of
unaddress and un-handled SOCK_NOSPACE.

v2: use csk_mem_free where appropriate
    proper indent of goto do_nonblock
    replace out with do_rm_wq

Reported-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Atul Gupta <atul.gupta@chelsio.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This commit is contained in:
Atul Gupta 2018-05-27 21:15:19 +05:30 committed by Herbert Xu
parent 09e53d8289
commit 3b8305f5c8
3 changed files with 89 additions and 3 deletions

View file

@ -144,6 +144,7 @@ struct chtls_dev {
struct list_head rcu_node;
struct list_head na_node;
unsigned int send_page_order;
int max_host_sndbuf;
struct key_map kmap;
};

View file

@ -914,6 +914,78 @@ static u16 tls_header_read(struct tls_hdr *thdr, struct iov_iter *from)
return (__force u16)cpu_to_be16(thdr->length);
}
static int csk_mem_free(struct chtls_dev *cdev, struct sock *sk)
{
return (cdev->max_host_sndbuf - sk->sk_wmem_queued);
}
static int csk_wait_memory(struct chtls_dev *cdev,
struct sock *sk, long *timeo_p)
{
DEFINE_WAIT_FUNC(wait, woken_wake_function);
int sndbuf, err = 0;
long current_timeo;
long vm_wait = 0;
bool noblock;
current_timeo = *timeo_p;
noblock = (*timeo_p ? false : true);
sndbuf = cdev->max_host_sndbuf;
if (csk_mem_free(cdev, sk)) {
current_timeo = (prandom_u32() % (HZ / 5)) + 2;
vm_wait = (prandom_u32() % (HZ / 5)) + 2;
}
add_wait_queue(sk_sleep(sk), &wait);
while (1) {
sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk);
if (sk->sk_err || (sk->sk_shutdown & SEND_SHUTDOWN))
goto do_error;
if (!*timeo_p) {
if (noblock)
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
goto do_nonblock;
}
if (signal_pending(current))
goto do_interrupted;
sk_clear_bit(SOCKWQ_ASYNC_NOSPACE, sk);
if (csk_mem_free(cdev, sk) && !vm_wait)
break;
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
sk->sk_write_pending++;
sk_wait_event(sk, &current_timeo, sk->sk_err ||
(sk->sk_shutdown & SEND_SHUTDOWN) ||
(csk_mem_free(cdev, sk) && !vm_wait), &wait);
sk->sk_write_pending--;
if (vm_wait) {
vm_wait -= current_timeo;
current_timeo = *timeo_p;
if (current_timeo != MAX_SCHEDULE_TIMEOUT) {
current_timeo -= vm_wait;
if (current_timeo < 0)
current_timeo = 0;
}
vm_wait = 0;
}
*timeo_p = current_timeo;
}
do_rm_wq:
remove_wait_queue(sk_sleep(sk), &wait);
return err;
do_error:
err = -EPIPE;
goto do_rm_wq;
do_nonblock:
err = -EAGAIN;
goto do_rm_wq;
do_interrupted:
err = sock_intr_errno(*timeo_p);
goto do_rm_wq;
}
int chtls_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
{
struct chtls_sock *csk = rcu_dereference_sk_user_data(sk);
@ -952,6 +1024,8 @@ int chtls_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
copy = mss - skb->len;
skb->ip_summed = CHECKSUM_UNNECESSARY;
}
if (!csk_mem_free(cdev, sk))
goto wait_for_sndbuf;
if (is_tls_tx(csk) && !csk->tlshws.txleft) {
struct tls_hdr hdr;
@ -1099,8 +1173,10 @@ int chtls_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
if (ULP_SKB_CB(skb)->flags & ULPCB_FLAG_NO_APPEND)
push_frames_if_head(sk);
continue;
wait_for_sndbuf:
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
wait_for_memory:
err = sk_stream_wait_memory(sk, &timeo);
err = csk_wait_memory(cdev, sk, &timeo);
if (err)
goto do_error;
}
@ -1131,6 +1207,7 @@ int chtls_sendpage(struct sock *sk, struct page *page,
int offset, size_t size, int flags)
{
struct chtls_sock *csk;
struct chtls_dev *cdev;
int mss, err, copied;
struct tcp_sock *tp;
long timeo;
@ -1138,6 +1215,7 @@ int chtls_sendpage(struct sock *sk, struct page *page,
tp = tcp_sk(sk);
copied = 0;
csk = rcu_dereference_sk_user_data(sk);
cdev = csk->cdev;
timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
err = sk_stream_wait_connect(sk, &timeo);
@ -1156,6 +1234,8 @@ int chtls_sendpage(struct sock *sk, struct page *page,
if (!skb || (ULP_SKB_CB(skb)->flags & ULPCB_FLAG_NO_APPEND) ||
copy <= 0) {
new_buf:
if (!csk_mem_free(cdev, sk))
goto wait_for_sndbuf;
if (is_tls_tx(csk)) {
skb = get_record_skb(sk,
@ -1167,7 +1247,7 @@ int chtls_sendpage(struct sock *sk, struct page *page,
skb = get_tx_skb(sk, 0);
}
if (!skb)
goto do_error;
goto wait_for_memory;
copy = mss;
}
if (copy > size)
@ -1206,8 +1286,12 @@ int chtls_sendpage(struct sock *sk, struct page *page,
if (unlikely(ULP_SKB_CB(skb)->flags & ULPCB_FLAG_NO_APPEND))
push_frames_if_head(sk);
continue;
wait_for_sndbuf:
set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
wait_for_memory:
err = csk_wait_memory(cdev, sk, &timeo);
if (err)
goto do_error;
}
out:
csk_reset_flag(csk, CSK_TX_MORE_DATA);

View file

@ -238,6 +238,7 @@ static void *chtls_uld_add(const struct cxgb4_lld_info *info)
spin_lock_init(&cdev->idr_lock);
cdev->send_page_order = min_t(uint, get_order(32768),
send_page_order);
cdev->max_host_sndbuf = 48 * 1024;
if (lldi->vr->key.size)
if (chtls_init_kmap(cdev, lldi))