kernel/linux.git/include/net/sock.h, branch v4.19.67

packets: Always register packet sk in the same order

2019-04-03T04:26:17+00:00

[ Upstream commit a4dc6a49156b1f8d6e17251ffda17c9e6a5db78a ] When using fanouts with AF_PACKET, the demux functions such as fanout_demux_cpu will return an index in the fanout socket array, which corresponds to the selected socket. The ordering of this array depends on the order the sockets were added to a given fanout group, so for FANOUT_CPU this means sockets are bound to cpus in the order they are configured, which is OK. However, when stopping then restarting the interface these sockets are bound to, the sockets are reassigned to the fanout group in the reverse order, due to the fact that they were inserted at the head of the interface's AF_PACKET socket list. This means that traffic that was directed to the first socket in the fanout group is now directed to the last one after an interface restart. In the case of FANOUT_CPU, traffic from CPU0 will be directed to the socket that used to receive traffic from the last CPU after an interface restart. This commit introduces a helper to add a socket at the tail of a list, then uses it to register AF_PACKET sockets. Note that this changes the order in which sockets are listed in /proc and with sock_diag. Fixes: dc99f600698d ("packet: Add fanout support") Signed-off-by: Maxime Chevallier Acked-by: Willem de Bruijn Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

sock: Make sock->sk_stamp thread-safe

2019-01-09T16:38:33+00:00

[ Upstream commit 3a0ed3e9619738067214871e9cb826fa23b2ddb9 ] Al Viro mentioned (Message-ID <20170626041334.GZ10672@ZenIV.linux.org.uk>) that there is probably a race condition lurking in accesses of sk_stamp on 32-bit machines. sock->sk_stamp is of type ktime_t which is always an s64. On a 32 bit architecture, we might run into situations of unsafe access as the access to the field becomes non atomic. Use seqlocks for synchronization. This allows us to avoid using spinlocks for readers as readers do not need mutual exclusion. Another approach to solve this is to require sk_lock for all modifications of the timestamps. The current approach allows for timestamps to have their own lock: sk_stamp_lock. This allows for the patch to not compete with already existing critical sections, and side effects are limited to the paths in the patch. The addition of the new field maintains the data locality optimizations from commit 9115e8cd2a0c ("net: reorganize struct sock for better data locality") Note that all the instances of the sk_stamp accesses are either through the ioctl or the syscall recvmsg. Signed-off-by: Deepa Dinamani Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

tcp: do not release socket ownership in tcp_close()

2018-12-01T08:37:28+00:00

commit 8873c064d1de579ea23412a6d3eee972593f142b upstream. syzkaller was able to hit the WARN_ON(sock_owned_by_user(sk)); in tcp_close() While a socket is being closed, it is very possible other threads find it in rtnetlink dump. tcp_get_info() will acquire the socket lock for a short amount of time (slow = lock_sock_fast(sk)/unlock_sock_fast(sk, slow);), enough to trigger the warning. Fixes: 67db3e4bfbc9 ("tcp: no longer hold ehash lock while calling tcp_get_info()") Signed-off-by: Eric Dumazet Reported-by: syzbot Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

Revert "net: simplify sock_poll_wait"

2018-11-04T13:50:51+00:00

[ Upstream commit 89ab066d4229acd32e323f1569833302544a4186 ] This reverts commit dd979b4df817e9976f18fb6f9d134d6bc4a3c317. This broke tcp_poll for SMC fallback: An AF_SMC socket establishes an internal TCP socket for the initial handshake with the remote peer. Whenever the SMC connection can not be established this TCP socket is used as a fallback. All socket operations on the SMC socket are then forwarded to the TCP socket. In case of poll, the file->private_data pointer references the SMC socket because the TCP socket has no file assigned. This causes tcp_poll to wait on the wrong socket. Signed-off-by: Karsten Graul Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: remove bogus RCU annotations on socket.wq

2018-07-31T19:40:22+00:00

We never use RCU protection for it, just a lot of cargo-cult rcu_deference_protects calls. Note that we do keep the kfree_rcu call for it, as the references through struct sock are RCU protected and thus might require a grace period before freeing. Signed-off-by: Christoph Hellwig Reviewed-by: Eric Dumazet Acked-by: Paul E. McKenney Signed-off-by: David S. Miller

net: don not detour through struct sock to find the poll waitqueue

2018-07-30T16:10:25+00:00

For any open socket file descriptor sock->sk->sk_wq->wait will always point to sock->wq->wait. That means we can do the shorter dereference and removal a NULL check and don't have to not worry about any RCU protection. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

net: simplify sock_poll_wait

2018-07-30T16:10:25+00:00

The wait_address argument is always directly derived from the filp argument, so remove it. Signed-off-by: Christoph Hellwig Signed-off-by: David S. Miller

sock: sockc cookie initializer

2018-07-07T01:58:49+00:00

Initialize the cookie in one location to reduce code duplication and avoid bugs from inconsistent initialization, such as that fixed in commit 9887cba19978 ("ip: limit use of gso_size to udp"). Signed-off-by: Willem de Bruijn Signed-off-by: David S. Miller

net/sched: Make etf report drops on error_queue

2018-07-04T13:30:28+00:00

Use the socket error queue for reporting dropped packets if the socket has enabled that feature through the SO_TXTIME API. Packets are dropped either on enqueue() if they aren't accepted by the qdisc or on dequeue() if the system misses their deadline. Those are reported as different errors so applications can react accordingly. Userspace can retrieve the errors through the socket error queue and the corresponding cmsg interfaces. A struct sock_extended_err* is used for returning the error data, and the packet's timestamp can be retrieved by adding both ee_data and ee_info fields as e.g.: ((__u64) serr->ee_data << 32) + serr->ee_info This feature is disabled by default and must be explicitly enabled by applications. Enabling it can bring some overhead for the Tx cycles of the application. Signed-off-by: Jesus Sanchez-Palencia Signed-off-by: David S. Miller

net: Add a new socket option for a future transmit time.

2018-07-04T13:30:27+00:00

This patch introduces SO_TXTIME. User space enables this option in order to pass a desired future transmit time in a CMSG when calling sendmsg(2). The argument to this socket option is a 8-bytes long struct provided by the uapi header net_tstamp.h defined as: struct sock_txtime { clockid_t clockid; u32 flags; }; Note that new fields were added to struct sock by filling a 2-bytes hole found in the struct. For that reason, neither the struct size or number of cachelines were altered. Signed-off-by: Richard Cochran Signed-off-by: Jesus Sanchez-Palencia Signed-off-by: David S. Miller