tcp: detecting the misuse of .sendpage for Slab objects

sendpage was not designed for processing of the Slab pages,
in some situations it can trigger BUG_ON on receiving side.

Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Vasily Averin 2019-03-06 14:10:22 +03:00 committed by David S. Miller
parent 7b83762376
commit a10674bf24

View File

@ -943,6 +943,10 @@ ssize_t do_tcp_sendpages(struct sock *sk, struct page *page, int offset,
ssize_t copied;
long timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT);
if (IS_ENABLED(CONFIG_DEBUG_VM) &&
WARN_ONCE(PageSlab(page), "page must not be a Slab one"))
return -EINVAL;
/* Wait for a connection to finish. One exception is TCP Fast Open
* (passive side) where data is allowed to be sent before a connection
* is fully established.