| Message ID | 2a77e65a-9d81-9ddb-f7af-b3b6da095a10@virtuozzo.com |
|---|---|
| State | Accepted |
| Delegated to: | David Miller |
| Headers | show |
| Series | tcp: detecting the misuse of .sendpage for Slab objects | expand |
On 03/06/2019 03:10 AM, Vasily Averin wrote: > 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> > --- > net/ipv4/tcp.c | 4 ++++ > 1 file changed, 4 insertions(+) > > diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c > index ad07dd71063d..dbb08140cdc9 100644 > --- a/net/ipv4/tcp.c > +++ b/net/ipv4/tcp.c > @@ -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. > SGTM David, this probably can be merged into net tree. Signed-off-by: Eric Dumazet <edumazet@google.com>
From: Vasily Averin <vvs@virtuozzo.com> Date: Wed, 6 Mar 2019 14:10:22 +0300 > 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> Applied.
diff --git a/net/ipv4/tcp.c b/net/ipv4/tcp.c index ad07dd71063d..dbb08140cdc9 100644 --- a/net/ipv4/tcp.c +++ b/net/ipv4/tcp.c @@ -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.
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> --- net/ipv4/tcp.c | 4 ++++ 1 file changed, 4 insertions(+)