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* net: core: add READ_ONCE/WRITE_ONCE annotations for sk->sk_bound_dev_ifEric Dumazet2022-05-161-4/+7
| | | | | | | | | | | sock_bindtoindex_locked() needs to use WRITE_ONCE(sk->sk_bound_dev_if, val), because other cpus/threads might locklessly read this field. sock_getbindtodevice(), sock_getsockopt() need READ_ONCE() because they run without socket lock held. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: allow gso_max_size to exceed 65536Alexander Duyck2022-05-161-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | The code for gso_max_size was added originally to allow for debugging and workaround of buggy devices that couldn't support TSO with blocks 64K in size. The original reason for limiting it to 64K was because that was the existing limits of IPv4 and non-jumbogram IPv6 length fields. With the addition of Big TCP we can remove this limit and allow the value to potentially go up to UINT_MAX and instead be limited by the tso_max_size value. So in order to support this we need to go through and clean up the remaining users of the gso_max_size value so that the values will cap at 64K for non-TCPv6 flows. In addition we can clean up the GSO_MAX_SIZE value so that 64K becomes GSO_LEGACY_MAX_SIZE and UINT_MAX will now be the upper limit for GSO_MAX_SIZE. v6: (edumazet) fixed a compile error if CONFIG_IPV6=n, in a new sk_trim_gso_size() helper. netif_set_tso_max_size() caps the requested TSO size with GSO_MAX_SIZE. Signed-off-by: Alexander Duyck <alexanderduyck@fb.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: align SO_RCVMARK required privileges with SO_MARKEyal Birger2022-05-051-0/+6
| | | | | | | | | | | | | | The commit referenced in the "Fixes" tag added the SO_RCVMARK socket option for receiving the skb mark in the ancillary data. Since this is a new capability, and exposes admin configured details regarding the underlying network setup to sockets, let's align the needed capabilities with those of SO_MARK. Fixes: 6fd1d51cfa25 ("net: SO_RCVMARK socket option for SO_MARK with recvmsg()") Signed-off-by: Eyal Birger <eyal.birger@gmail.com> Link: https://lore.kernel.org/r/20220504095459.2663513-1-eyal.birger@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* sock: optimise sock_def_write_space barriersPavel Begunkov2022-05-011-1/+25
| | | | | | | | | | | | Now we have a separate path for sock_def_write_space() and can go one step further. When it's called from sock_wfree() we know that there is a preceding atomic for putting down ->sk_wmem_alloc. We can use it to replace to replace smb_mb() with a less expensive smp_mb__after_atomic(). It also removes an extra RCU read lock/unlock as a small bonus. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sock: optimise UDP sock_wfree() refcountingPavel Begunkov2022-05-011-0/+14
| | | | | | | | | | | | | | | | | | For non SOCK_USE_WRITE_QUEUE sockets, sock_wfree() (atomically) puts ->sk_wmem_alloc twice. It's needed to keep the socket alive while calling ->sk_write_space() after the first put. However, some sockets, such as UDP, are freed by RCU (i.e. SOCK_RCU_FREE) and use already RCU-safe sock_def_write_space(). Carve a fast path for such sockets, put down all refs in one go before calling sock_def_write_space() but guard the socket from being freed by an RCU read section. note: because TCP sockets are marked with SOCK_USE_WRITE_QUEUE it doesn't add extra checks in its path. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sock: dedup sock_def_write_space wmem_alloc checksPavel Begunkov2022-05-011-3/+2
| | | | | | | | | | Except for minor rounding differences the first ->sk_wmem_alloc test in sock_def_write_space() is a hand coded version of sock_writeable(). Replace it with the helper, and also kill the following if duplicating the check. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: inline sock_alloc_send_skbPavel Begunkov2022-04-301-7/+0
| | | | | | | | sock_alloc_send_skb() is simple and just proxying to another function, so we can inline it and cut associated overhead. Signed-off-by: Pavel Begunkov <asml.silence@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: SO_RCVMARK socket option for SO_MARK with recvmsg()Erin MacNeil2022-04-281-0/+7
| | | | | | | | | | | | | | Adding a new socket option, SO_RCVMARK, to indicate that SO_MARK should be included in the ancillary data returned by recvmsg(). Renamed the sock_recv_ts_and_drops() function to sock_recv_cmsgs(). Signed-off-by: Erin MacNeil <lnx.erin@gmail.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Acked-by: Marc Kleine-Budde <mkl@pengutronix.de> Link: https://lore.kernel.org/r/20220427200259.2564-1-lnx.erin@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* net: generalize skb freeing deferral to per-cpu listsEric Dumazet2022-04-261-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Logic added in commit f35f821935d8 ("tcp: defer skb freeing after socket lock is released") helped bulk TCP flows to move the cost of skbs frees outside of critical section where socket lock was held. But for RPC traffic, or hosts with RFS enabled, the solution is far from being ideal. For RPC traffic, recvmsg() has to return to user space right after skb payload has been consumed, meaning that BH handler has no chance to pick the skb before recvmsg() thread. This issue is more visible with BIG TCP, as more RPC fit one skb. For RFS, even if BH handler picks the skbs, they are still picked from the cpu on which user thread is running. Ideally, it is better to free the skbs (and associated page frags) on the cpu that originally allocated them. This patch removes the per socket anchor (sk->defer_list) and instead uses a per-cpu list, which will hold more skbs per round. This new per-cpu list is drained at the end of net_action_rx(), after incoming packets have been processed, to lower latencies. In normal conditions, skbs are added to the per-cpu list with no further action. In the (unlikely) cases where the cpu does not run net_action_rx() handler fast enough, we use an IPI to raise NET_RX_SOFTIRQ on the remote cpu. Also, we do not bother draining the per-cpu list from dev_cpu_dead() This is because skbs in this list have no requirement on how fast they should be freed. Note that we can add in the future a small per-cpu cache if we see any contention on sd->defer_lock. Tested on a pair of hosts with 100Gbit NIC, RFS enabled, and /proc/sys/net/ipv4/tcp_rmem[2] tuned to 16MB to work around page recycling strategy used by NIC driver (its page pool capacity being too small compared to number of skbs/pages held in sockets receive queues) Note that this tuning was only done to demonstrate worse conditions for skb freeing for this particular test. These conditions can happen in more general production workload. 10 runs of one TCP_STREAM flow Before: Average throughput: 49685 Mbit. Kernel profiles on cpu running user thread recvmsg() show high cost for skb freeing related functions (*) 57.81% [kernel] [k] copy_user_enhanced_fast_string (*) 12.87% [kernel] [k] skb_release_data (*) 4.25% [kernel] [k] __free_one_page (*) 3.57% [kernel] [k] __list_del_entry_valid 1.85% [kernel] [k] __netif_receive_skb_core 1.60% [kernel] [k] __skb_datagram_iter (*) 1.59% [kernel] [k] free_unref_page_commit (*) 1.16% [kernel] [k] __slab_free 1.16% [kernel] [k] _copy_to_iter (*) 1.01% [kernel] [k] kfree (*) 0.88% [kernel] [k] free_unref_page 0.57% [kernel] [k] ip6_rcv_core 0.55% [kernel] [k] ip6t_do_table 0.54% [kernel] [k] flush_smp_call_function_queue (*) 0.54% [kernel] [k] free_pcppages_bulk 0.51% [kernel] [k] llist_reverse_order 0.38% [kernel] [k] process_backlog (*) 0.38% [kernel] [k] free_pcp_prepare 0.37% [kernel] [k] tcp_recvmsg_locked (*) 0.37% [kernel] [k] __list_add_valid 0.34% [kernel] [k] sock_rfree 0.34% [kernel] [k] _raw_spin_lock_irq (*) 0.33% [kernel] [k] __page_cache_release 0.33% [kernel] [k] tcp_v6_rcv (*) 0.33% [kernel] [k] __put_page (*) 0.29% [kernel] [k] __mod_zone_page_state 0.27% [kernel] [k] _raw_spin_lock After patch: Average throughput: 73076 Mbit. Kernel profiles on cpu running user thread recvmsg() looks better: 81.35% [kernel] [k] copy_user_enhanced_fast_string 1.95% [kernel] [k] _copy_to_iter 1.95% [kernel] [k] __skb_datagram_iter 1.27% [kernel] [k] __netif_receive_skb_core 1.03% [kernel] [k] ip6t_do_table 0.60% [kernel] [k] sock_rfree 0.50% [kernel] [k] tcp_v6_rcv 0.47% [kernel] [k] ip6_rcv_core 0.45% [kernel] [k] read_tsc 0.44% [kernel] [k] _raw_spin_lock_irqsave 0.37% [kernel] [k] _raw_spin_lock 0.37% [kernel] [k] native_irq_return_iret 0.33% [kernel] [k] __inet6_lookup_established 0.31% [kernel] [k] ip6_protocol_deliver_rcu 0.29% [kernel] [k] tcp_rcv_established 0.29% [kernel] [k] llist_reverse_order v2: kdoc issue (kernel bots) do not defer if (alloc_cpu == smp_processor_id()) (Paolo) replace the sk_buff_head with a single-linked list (Jakub) add a READ_ONCE()/WRITE_ONCE() for the lockless read of sd->defer_list Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Paolo Abeni <pabeni@redhat.com> Link: https://lore.kernel.org/r/20220422201237.416238-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* net: remove noblock parameter from recvmsg() entitiesOliver Hartkopp2022-04-121-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | The internal recvmsg() functions have two parameters 'flags' and 'noblock' that were merged inside skb_recv_datagram(). As a follow up patch to commit f4b41f062c42 ("net: remove noblock parameter from skb_recv_datagram()") this patch removes the separate 'noblock' parameter for recvmsg(). Analogue to the referenced patch for skb_recv_datagram() the 'flags' and 'noblock' parameters are unnecessarily split up with e.g. err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT, flags & ~MSG_DONTWAIT, &addr_len); or in err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg, sk, msg, size, flags & MSG_DONTWAIT, flags & ~MSG_DONTWAIT, &addr_len); instead of simply using only flags all the time and check for MSG_DONTWAIT where needed (to preserve for the formerly separated no(n)block condition). Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net> Link: https://lore.kernel.org/r/20220411124955.154876-1-socketcan@hartkopp.net Signed-off-by: Paolo Abeni <pabeni@redhat.com>
* net: sock: introduce sock_queue_rcv_skb_reason()Menglong Dong2022-04-111-6/+24
| | | | | | | | | | | | | | | | | | | In order to report the reasons of skb drops in 'sock_queue_rcv_skb()', introduce the function 'sock_queue_rcv_skb_reason()'. As the return value of 'sock_queue_rcv_skb()' is used as the error code, we can't make it as drop reason and have to pass extra output argument. 'sock_queue_rcv_skb()' is used in many places, so we can't change it directly. Introduce the new function 'sock_queue_rcv_skb_reason()' and make 'sock_queue_rcv_skb()' an inline call to it. Reviewed-by: Hao Peng <flyingpeng@tencent.com> Reviewed-by: Jiang Biao <benbjiang@tencent.com> Signed-off-by: Menglong Dong <imagedong@tencent.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: extract a few internals from netdevice.hJakub Kicinski2022-04-071-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | There's a number of functions and static variables used under net/core/ but not from the outside. We currently dump most of them into netdevice.h. That bad for many reasons: - netdevice.h is very cluttered, hard to figure out what the APIs are; - netdevice.h is very long; - we have to touch netdevice.h more which causes expensive incremental builds. Create a header under net/core/ and move some declarations. The new header is also a bit of a catch-all but that's fine, if we create more specific headers people will likely over-think where their declaration fit best. And end up putting them in netdevice.h, again. More work should be done on splitting netdevice.h into more targeted headers, but that'd be more time consuming so small steps. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* SO_ZEROCOPY should return -EOPNOTSUPP rather than -ENOTSUPPSamuel Thibault2022-03-081-2/+2
| | | | | | | | | | | | | | | | ENOTSUPP is documented as "should never be seen by user programs", and thus not exposed in <errno.h>, and thus applications cannot safely check against it (they get "Unknown error 524" as strerror). We should rather return the well-known -EOPNOTSUPP. This is similar to 2230a7ef5198 ("drop_monitor: Use correct error code") and 4a5cdc604b9c ("net/tls: Fix return values to avoid ENOTSUPP"), which did not seem to cause problems. Signed-off-by: Samuel Thibault <samuel.thibault@labri.fr> Acked-by: Willem de Bruijn <willemb@google.com> Link: https://lore.kernel.org/r/20220307223126.djzvg44v2o2jkjsx@begin Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2022-02-241-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | tools/testing/selftests/net/mptcp/mptcp_join.sh 34aa6e3bccd8 ("selftests: mptcp: add ip mptcp wrappers") 857898eb4b28 ("selftests: mptcp: add missing join check") 6ef84b1517e0 ("selftests: mptcp: more robust signal race test") https://lore.kernel.org/all/20220221131842.468893-1-broonie@kernel.org/ drivers/net/ethernet/mellanox/mlx5/core/en/tc/act/act.h drivers/net/ethernet/mellanox/mlx5/core/en/tc/act/ct.c fb7e76ea3f3b6 ("net/mlx5e: TC, Skip redundant ct clear actions") c63741b426e11 ("net/mlx5e: Fix MPLSoUDP encap to use MPLS action information") 09bf97923224f ("net/mlx5e: TC, Move pedit_headers_action to parse_attr") 84ba8062e383 ("net/mlx5e: Test CT and SAMPLE on flow attr") efe6f961cd2e ("net/mlx5e: CT, Don't set flow flag CT for ct clear flow") 3b49a7edec1d ("net/mlx5e: TC, Reject rules with multiple CT actions") Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| * net-timestamp: convert sk->sk_tskey to atomic_tEric Dumazet2022-02-181-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | UDP sendmsg() can be lockless, this is causing all kinds of data races. This patch converts sk->sk_tskey to remove one of these races. BUG: KCSAN: data-race in __ip_append_data / __ip_append_data read to 0xffff8881035d4b6c of 4 bytes by task 8877 on cpu 1: __ip_append_data+0x1c1/0x1de0 net/ipv4/ip_output.c:994 ip_make_skb+0x13f/0x2d0 net/ipv4/ip_output.c:1636 udp_sendmsg+0x12bd/0x14c0 net/ipv4/udp.c:1249 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:819 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg net/socket.c:725 [inline] ____sys_sendmsg+0x39a/0x510 net/socket.c:2413 ___sys_sendmsg net/socket.c:2467 [inline] __sys_sendmmsg+0x267/0x4c0 net/socket.c:2553 __do_sys_sendmmsg net/socket.c:2582 [inline] __se_sys_sendmmsg net/socket.c:2579 [inline] __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2579 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae write to 0xffff8881035d4b6c of 4 bytes by task 8880 on cpu 0: __ip_append_data+0x1d8/0x1de0 net/ipv4/ip_output.c:994 ip_make_skb+0x13f/0x2d0 net/ipv4/ip_output.c:1636 udp_sendmsg+0x12bd/0x14c0 net/ipv4/udp.c:1249 inet_sendmsg+0x5f/0x80 net/ipv4/af_inet.c:819 sock_sendmsg_nosec net/socket.c:705 [inline] sock_sendmsg net/socket.c:725 [inline] ____sys_sendmsg+0x39a/0x510 net/socket.c:2413 ___sys_sendmsg net/socket.c:2467 [inline] __sys_sendmmsg+0x267/0x4c0 net/socket.c:2553 __do_sys_sendmmsg net/socket.c:2582 [inline] __se_sys_sendmmsg net/socket.c:2579 [inline] __x64_sys_sendmmsg+0x53/0x60 net/socket.c:2579 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae value changed: 0x0000054d -> 0x0000054e Reported by Kernel Concurrency Sanitizer on: CPU: 0 PID: 8880 Comm: syz-executor.5 Not tainted 5.17.0-rc2-syzkaller-00167-gdcb85f85fa6f-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Fixes: 09c2d251b707 ("net-timestamp: add key to disambiguate concurrent datagrams") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: Willem de Bruijn <willemb@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: add sanity check in proto_register()Eric Dumazet2022-02-171-0/+4
| | | | | | | | | | | | | | | | | | | | | | | | prot->memory_allocated should only be set if prot->sysctl_mem is also set. This is a followup of commit 25206111512d ("crypto: af_alg - get rid of alg_memory_allocated"). Signed-off-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20220216171801.3604366-1-eric.dumazet@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* | net: allow SO_MARK with CAP_NET_RAW via cmsgJakub Kicinski2022-02-011-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | There's not reason SO_MARK would be allowed via setsockopt() and not via cmsg, let's keep the two consistent. See commit 079925cce1d0 ("net: allow SO_MARK with CAP_NET_RAW") for justification why NET_RAW -> SO_MARK is safe. Reviewed-by: Maciej Żenczykowski <maze@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20220131233357.52964-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* | tcp: Change SYN ACK retransmit behaviour to account for rehashAkhmat Karakotov2022-01-311-1/+2
| | | | | | | | | | | | | | | | | | | | Disabling rehash behavior did not affect SYN ACK retransmits because hash was forcefully changed bypassing the sk_rethink_hash function. This patch adds a condition which checks for rehash mode before resetting hash. Signed-off-by: Akhmat Karakotov <hmukos@yandex-team.ru> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | txhash: Add socket option to control TX hash rethink behaviorAkhmat Karakotov2022-01-311-0/+13
| | | | | | | | | | | | | | | | | | | | | | Add the SO_TXREHASH socket option to control hash rethink behavior per socket. When default mode is set, sockets disable rehash at initialization and use sysctl option when entering listen state. setsockopt() overrides default behavior. Signed-off-by: Akhmat Karakotov <hmukos@yandex-team.ru> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: Adjust sk_gso_max_size once when setDavid Ahern2022-01-251-0/+1
|/ | | | | | | | | | | | sk_gso_max_size is set based on the dst dev. Both users of it adjust the value by the same offset - (MAX_TCP_HEADER + 1). Rather than compute the same adjusted value on each call do the adjustment once when set. Signed-off-by: David Ahern <dsahern@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://lore.kernel.org/r/20220125024511.27480-1-dsahern@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* net: Flush deferred skb free on socket destroyGal Pressman2022-01-171-0/+3
| | | | | | | | | | | The cited Fixes patch moved to a deferred skb approach where the skbs are not freed immediately under the socket lock. Add a WARN_ON_ONCE() to verify the deferred list is empty on socket destroy, and empty it to prevent potential memory leaks. Fixes: f35f821935d8 ("tcp: defer skb freeing after socket lock is released") Signed-off-by: Gal Pressman <gal@nvidia.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: fix sock_timestamping_bind_phc() to release deviceMiroslav Lichvar2022-01-121-0/+2
| | | | | | | | | | Don't forget to release the device in sock_timestamping_bind_phc() after it was used to get the vclock indices. Fixes: d463126e23f1 ("net: sock: extend SO_TIMESTAMPING for PHC binding") Signed-off-by: Miroslav Lichvar <mlichvar@redhat.com> Cc: Yangbo Lu <yangbo.lu@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sock: Use sock_owned_by_user_nocheck() instead of sk_lock.owned.Kuniyuki Iwashima2021-12-101-2/+2
| | | | | | | | | This patch moves sock_release_ownership() down in include/net/sock.h and replaces some sk_lock.owned tests with sock_owned_by_user_nocheck(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp> Link: https://lore.kernel.org/r/20211208062158.54132-1-kuniyu@amazon.co.jp Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* net: add netns refcount tracker to struct sockEric Dumazet2021-12-101-3/+3
| | | | | Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* net: allow SO_MARK with CAP_NET_RAWMaciej Żenczykowski2021-11-241-1/+2
| | | | | | | | | | | | | | | | | | | | | A CAP_NET_RAW capable process can already spoof (on transmit) anything it desires via raw packet sockets... There is no good reason to not allow it to also be able to play routing tricks on packets from its own normal sockets. There is a desire to be able to use SO_MARK for routing table selection (via ip rule fwmark) from within a user process without having to run it as root. Granting it CAP_NET_RAW is much less dangerous than CAP_NET_ADMIN (CAP_NET_RAW doesn't permit persistent state change, while CAP_NET_ADMIN does - by for example allowing the reconfiguration of the routing tables and/or bringing up/down devices). Let's keep CAP_NET_ADMIN for persistent state changes, while using CAP_NET_RAW for non-configuration related stuff. Signed-off-by: Maciej Żenczykowski <maze@google.com> Link: https://lore.kernel.org/r/20211123203715.193413-1-zenczykowski@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* net: allow CAP_NET_RAW to setsockopt SO_PRIORITYMaciej Żenczykowski2021-11-241-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | CAP_NET_ADMIN is and should continue to be about configuring the system as a whole, not about configuring per-socket or per-packet parameters. Sending and receiving raw packets is what CAP_NET_RAW is all about. It can already send packets with any VLAN tag, and any IPv4 TOS mark, and any IPv6 TCLASS mark, simply by virtue of building such a raw packet. Not to mention using any protocol and source/ /destination ip address/port tuple. These are the fields that networking gear uses to prioritize packets. Hence, a CAP_NET_RAW process is already capable of affecting traffic prioritization after it hits the wire. This change makes it capable of affecting traffic prioritization even in the host at the nic and before that in the queueing disciplines (provided skb->priority is actually being used for prioritization, and not the TOS/TCLASS field) Hence it makes sense to allow a CAP_NET_RAW process to set the priority of sockets and thus packets it sends. Signed-off-by: Maciej Żenczykowski <maze@google.com> Link: https://lore.kernel.org/r/20211123203702.193221-1-zenczykowski@gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
* net: annotate accesses to dev->gso_max_segsEric Dumazet2021-11-221-1/+2
| | | | | | | | | | | | | dev->gso_max_segs is written under RTNL protection, or when the device is not yet visible, but is read locklessly. Add netif_set_gso_max_segs() helper. Add the READ_ONCE()/WRITE_ONCE() pairs, and use netif_set_gso_max_segs() where we can to better document what is going on. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: annotate accesses to dev->gso_max_sizeEric Dumazet2021-11-221-1/+2
| | | | | | | | | | | dev->gso_max_size is written under RTNL protection, or when the device is not yet visible, but is read locklessly. Add the READ_ONCE()/WRITE_ONCE() pairs, and use netif_set_gso_max_size() where we can to better document what is going on. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2021-11-181-3/+3
|\ | | | | | | Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| * sock: fix /proc/net/sockstat underflow in sk_clone_lock()Tetsuo Handa2021-11-151-3/+3
| | | | | | | | | | | | | | | | | | | | sk_clone_lock() needs to call sock_inuse_add(1) before entering the sk_free_unlock_clone() error path, for __sk_free() from sk_free() from sk_free_unlock_clone() calls sock_inuse_add(-1). Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Fixes: 648845ab7e200993 ("sock: Move the socket inuse to namespace.") Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: merge net->core.prot_inuse and net->core.sock_inuseEric Dumazet2021-11-161-11/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | net->core.sock_inuse is a per cpu variable (int), while net->core.prot_inuse is another per cpu variable of 64 integers. per cpu allocator tend to place them in very different places. Grouping them together makes sense, since it makes updates potentially faster, if hitting the same cache line. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: make sock_inuse_add() availableEric Dumazet2021-11-161-10/+0
| | | | | | | | | | | | | | MPTCP hard codes it, let us instead provide this helper. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: inline sock_prot_inuse_add()Eric Dumazet2021-11-161-11/+0
| | | | | | | | | | | | | | sock_prot_inuse_add() is very small, we can inline it. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | tcp: add RETPOLINE mitigation to sk_backlog_rcvEric Dumazet2021-11-161-1/+4
| | | | | | | | | | | | | | | | Use INDIRECT_CALL_INET() to avoid an indirect call when/if CONFIG_RETPOLINE=y Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: remove sk_route_nocapsEric Dumazet2021-11-161-1/+2
| | | | | | | | | | | | | | | | | | Instead of using a full netdev_features_t, we can use a single bit, as sk_route_nocaps is only used to remove NETIF_F_GSO_MASK from sk->sk_route_cap. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: remove sk_route_forced_capsEric Dumazet2021-11-161-1/+3
| | | | | | | | | | | | | | We were only using one bit, and we can replace it by sk_is_tcp() Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: use sk_is_tcp() in more placesEric Dumazet2021-11-161-4/+2
|/ | | | | | | Move sk_is_tcp() to include/net/sock.h and use it where we can. Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: fix possible NULL deref in sock_reserve_memoryEric Dumazet2021-11-041-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Sanity check in sock_reserve_memory() was not enough to prevent malicious user to trigger a NULL deref. In this case, the isse is that sk_prot->memory_allocated is NULL. Use standard sk_has_account() helper to deal with this. BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: null-ptr-deref in atomic_long_add_return include/linux/atomic/atomic-instrumented.h:1218 [inline] BUG: KASAN: null-ptr-deref in sk_memory_allocated_add include/net/sock.h:1371 [inline] BUG: KASAN: null-ptr-deref in sock_reserve_memory net/core/sock.c:994 [inline] BUG: KASAN: null-ptr-deref in sock_setsockopt+0x22ab/0x2b30 net/core/sock.c:1443 Write of size 8 at addr 0000000000000000 by task syz-executor.0/11270 CPU: 1 PID: 11270 Comm: syz-executor.0 Not tainted 5.15.0-syzkaller #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 04/01/2014 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 __kasan_report mm/kasan/report.c:446 [inline] kasan_report.cold+0x66/0xdf mm/kasan/report.c:459 check_region_inline mm/kasan/generic.c:183 [inline] kasan_check_range+0x13d/0x180 mm/kasan/generic.c:189 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic_long_add_return include/linux/atomic/atomic-instrumented.h:1218 [inline] sk_memory_allocated_add include/net/sock.h:1371 [inline] sock_reserve_memory net/core/sock.c:994 [inline] sock_setsockopt+0x22ab/0x2b30 net/core/sock.c:1443 __sys_setsockopt+0x4f8/0x610 net/socket.c:2172 __do_sys_setsockopt net/socket.c:2187 [inline] __se_sys_setsockopt net/socket.c:2184 [inline] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2184 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f56076d5ae9 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f5604c4b188 EFLAGS: 00000246 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 00007f56077e8f60 RCX: 00007f56076d5ae9 RDX: 0000000000000049 RSI: 0000000000000001 RDI: 0000000000000003 RBP: 00007f560772ff25 R08: 000000000000fec7 R09: 0000000000000000 R10: 0000000020000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fffb61a100f R14: 00007f5604c4b300 R15: 0000000000022000 </TASK> Fixes: 2bb2f5fb21b0 ("net: add new socket option SO_RESERVE_MEM") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: syzbot <syzkaller@googlegroups.com> Acked-by: Wei Wang <weiwan@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* vsock: Enable y2038 safe timeval for timeoutRichard Palethorpe2021-10-081-11/+24
| | | | | | | | | | | | | | | | | | | Reuse the timeval compat code from core/sock to handle 32-bit and 64-bit timeval structures. Also introduce a new socket option define to allow using y2038 safe timeval under 32-bit. The existing behavior of sock_set_timeout and vsock's timeout setter differ when the time value is out of bounds. vsocks current behavior is retained at the expense of not being able to share the full implementation. This allows the LTP test vsock01 to pass under 32-bit compat mode. Fixes: fe0c72f3db11 ("socket: move compat timeout handling into sock.c") Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com> Cc: Richard Palethorpe <rpalethorpe@richiejp.com> Reviewed-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski2021-09-301-24/+28
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | drivers/net/phy/bcm7xxx.c d88fd1b546ff ("net: phy: bcm7xxx: Fixed indirect MMD operations") f68d08c437f9 ("net: phy: bcm7xxx: Add EPHY entry for 72165") net/sched/sch_api.c b193e15ac69d ("net: prevent user from passing illegal stab size") 69508d43334e ("net_sched: Use struct_size() and flex_array_size() helpers") Both cases trivial - adjacent code additions. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
| * af_unix: fix races in sk_peer_pid and sk_peer_cred accessesEric Dumazet2021-09-301-6/+26
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Jann Horn reported that SO_PEERCRED and SO_PEERGROUPS implementations are racy, as af_unix can concurrently change sk_peer_pid and sk_peer_cred. In order to fix this issue, this patch adds a new spinlock that needs to be used whenever these fields are read or written. Jann also pointed out that l2cap_sock_get_peer_pid_cb() is currently reading sk->sk_peer_pid which makes no sense, as this field is only possibly set by AF_UNIX sockets. We will have to clean this in a separate patch. This could be done by reverting b48596d1dc25 "Bluetooth: L2CAP: Add get_peer_pid callback" or implementing what was truly expected. Fixes: 109f6e39fa07 ("af_unix: Allow SO_PEERCRED to work across namespaces.") Signed-off-by: Eric Dumazet <edumazet@google.com> Reported-by: Jann Horn <jannh@google.com> Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Luiz Augusto von Dentz <luiz.von.dentz@intel.com> Cc: Marcel Holtmann <marcel@holtmann.org> Signed-off-by: David S. Miller <davem@davemloft.net>
| * net: introduce and use lock_sock_fast_nested()Paolo Abeni2021-09-301-18/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Syzkaller reported a false positive deadlock involving the nl socket lock and the subflow socket lock: MPTCP: kernel_bind error, err=-98 ============================================ WARNING: possible recursive locking detected 5.15.0-rc1-syzkaller #0 Not tainted -------------------------------------------- syz-executor998/6520 is trying to acquire lock: ffff8880795718a0 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x267/0x7b0 net/mptcp/protocol.c:2738 but task is already holding lock: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1612 [inline] ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x23/0x7b0 net/mptcp/protocol.c:2720 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(k-sk_lock-AF_INET); lock(k-sk_lock-AF_INET); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by syz-executor998/6520: #0: ffffffff8d176c50 (cb_lock){++++}-{3:3}, at: genl_rcv+0x15/0x40 net/netlink/genetlink.c:802 #1: ffffffff8d176d08 (genl_mutex){+.+.}-{3:3}, at: genl_lock net/netlink/genetlink.c:33 [inline] #1: ffffffff8d176d08 (genl_mutex){+.+.}-{3:3}, at: genl_rcv_msg+0x3e0/0x580 net/netlink/genetlink.c:790 #2: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: lock_sock include/net/sock.h:1612 [inline] #2: ffff8880787c8c60 (k-sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_close+0x23/0x7b0 net/mptcp/protocol.c:2720 stack backtrace: CPU: 1 PID: 6520 Comm: syz-executor998 Not tainted 5.15.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_deadlock_bug kernel/locking/lockdep.c:2944 [inline] check_deadlock kernel/locking/lockdep.c:2987 [inline] validate_chain kernel/locking/lockdep.c:3776 [inline] __lock_acquire.cold+0x149/0x3ab kernel/locking/lockdep.c:5015 lock_acquire kernel/locking/lockdep.c:5625 [inline] lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5590 lock_sock_fast+0x36/0x100 net/core/sock.c:3229 mptcp_close+0x267/0x7b0 net/mptcp/protocol.c:2738 inet_release+0x12e/0x280 net/ipv4/af_inet.c:431 __sock_release net/socket.c:649 [inline] sock_release+0x87/0x1b0 net/socket.c:677 mptcp_pm_nl_create_listen_socket+0x238/0x2c0 net/mptcp/pm_netlink.c:900 mptcp_nl_cmd_add_addr+0x359/0x930 net/mptcp/pm_netlink.c:1170 genl_family_rcv_msg_doit+0x228/0x320 net/netlink/genetlink.c:731 genl_family_rcv_msg net/netlink/genetlink.c:775 [inline] genl_rcv_msg+0x328/0x580 net/netlink/genetlink.c:792 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2504 genl_rcv+0x24/0x40 net/netlink/genetlink.c:803 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline] netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1340 netlink_sendmsg+0x86d/0xdb0 net/netlink/af_netlink.c:1929 sock_sendmsg_nosec net/socket.c:704 [inline] sock_sendmsg+0xcf/0x120 net/socket.c:724 sock_no_sendpage+0x101/0x150 net/core/sock.c:2980 kernel_sendpage.part.0+0x1a0/0x340 net/socket.c:3504 kernel_sendpage net/socket.c:3501 [inline] sock_sendpage+0xe5/0x140 net/socket.c:1003 pipe_to_sendpage+0x2ad/0x380 fs/splice.c:364 splice_from_pipe_feed fs/splice.c:418 [inline] __splice_from_pipe+0x43e/0x8a0 fs/splice.c:562 splice_from_pipe fs/splice.c:597 [inline] generic_splice_sendpage+0xd4/0x140 fs/splice.c:746 do_splice_from fs/splice.c:767 [inline] direct_splice_actor+0x110/0x180 fs/splice.c:936 splice_direct_to_actor+0x34b/0x8c0 fs/splice.c:891 do_splice_direct+0x1b3/0x280 fs/splice.c:979 do_sendfile+0xae9/0x1240 fs/read_write.c:1249 __do_sys_sendfile64 fs/read_write.c:1314 [inline] __se_sys_sendfile64 fs/read_write.c:1300 [inline] __x64_sys_sendfile64+0x1cc/0x210 fs/read_write.c:1300 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f215cb69969 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 14 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc96bb3868 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f215cbad072 RCX: 00007f215cb69969 RDX: 0000000000000000 RSI: 0000000000000004 RDI: 0000000000000005 RBP: 0000000000000000 R08: 00007ffc96bb3a08 R09: 00007ffc96bb3a08 R10: 0000000100000002 R11: 0000000000000246 R12: 00007ffc96bb387c R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 the problem originates from uncorrect lock annotation in the mptcp code and is only visible since commit 2dcb96bacce3 ("net: core: Correct the sock::sk_lock.owned lockdep annotations"), but is present since the port-based endpoint support initial implementation. This patch addresses the issue introducing a nested variant of lock_sock_fast() and using it in the relevant code path. Fixes: 1729cf186d8a ("mptcp: create the listening socket for new port") Fixes: 2dcb96bacce3 ("net: core: Correct the sock::sk_lock.owned lockdep annotations") Suggested-by: Thomas Gleixner <tglx@linutronix.de> Reported-and-tested-by: syzbot+1dd53f7a89b299d59eaf@syzkaller.appspotmail.com Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>
* | net: add new socket option SO_RESERVE_MEMWei Wang2021-09-301-0/+69
|/ | | | | | | | | | | | | | | | | | | | | | This socket option provides a mechanism for users to reserve a certain amount of memory for the socket to use. When this option is set, kernel charges the user specified amount of memory to memcg, as well as sk_forward_alloc. This amount of memory is not reclaimable and is available in sk_forward_alloc for this socket. With this socket option set, the networking stack spends less cycles doing forward alloc and reclaim, which should lead to better system performance, with the cost of an amount of pre-allocated and unreclaimable memory, even under memory pressure. Note: This socket option is only available when memory cgroup is enabled and we require this reserved memory to be charged to the user's memcg. We hope this could avoid mis-behaving users to abused this feature to reserve a large amount on certain sockets and cause unfairness for others. Signed-off-by: Wei Wang <weiwan@google.com> Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net: core: Correct the sock::sk_lock.owned lockdep annotationsThomas Gleixner2021-09-191-14/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | lock_sock_fast() and lock_sock_nested() contain lockdep annotations for the sock::sk_lock.owned 'mutex'. sock::sk_lock.owned is not a regular mutex. It is just lockdep wise equivalent. In fact it's an open coded trivial mutex implementation with some interesting features. sock::sk_lock.slock is a regular spinlock protecting the 'mutex' representation sock::sk_lock.owned which is a plain boolean. If 'owned' is true, then some other task holds the 'mutex', otherwise it is uncontended. As this locking construct is obviously endangered by lock ordering issues as any other locking primitive it got lockdep annotated via a dedicated dependency map sock::sk_lock.dep_map which has to be updated at the lock and unlock sites. lock_sock_nested() is a straight forward 'mutex' lock operation: might_sleep(); spin_lock_bh(sock::sk_lock.slock) while (!try_lock(sock::sk_lock.owned)) { spin_unlock_bh(sock::sk_lock.slock); wait_for_release(); spin_lock_bh(sock::sk_lock.slock); } The lockdep annotation for sock::sk_lock.owned is for unknown reasons _after_ the lock has been acquired, i.e. after the code block above and after releasing sock::sk_lock.slock, but inside the bottom halves disabled region: spin_unlock(sock::sk_lock.slock); mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); local_bh_enable(); The placement after the unlock is obvious because otherwise the mutex_acquire() would nest into the spin lock held region. But that's from the lockdep perspective still the wrong place: 1) The mutex_acquire() is issued _after_ the successful acquisition which is pointless because in a dead lock scenario this point is never reached which means that if the deadlock is the first instance of exposing the wrong lock order lockdep does not have a chance to detect it. 2) It only works because lockdep is rather lax on the context from which the mutex_acquire() is issued. Acquiring a mutex inside a bottom halves and therefore non-preemptible region is obviously invalid, except for a trylock which is clearly not the case here. This 'works' stops working on RT enabled kernels where the bottom halves serialization is done via a local lock, which exposes this misplacement because the 'mutex' and the local lock nest the wrong way around and lockdep complains rightfully about a lock inversion. The placement is wrong since the initial commit a5b5bb9a053a ("[PATCH] lockdep: annotate sk_locks") which introduced this. Fix it by moving the mutex_acquire() in front of the actual lock acquisition, which is what the regular mutex_lock() operation does as well. lock_sock_fast() is not that straight forward. It looks at the first glance like a convoluted trylock operation: spin_lock_bh(sock::sk_lock.slock) if (!sock::sk_lock.owned) return false; while (!try_lock(sock::sk_lock.owned)) { spin_unlock_bh(sock::sk_lock.slock); wait_for_release(); spin_lock_bh(sock::sk_lock.slock); } spin_unlock(sock::sk_lock.slock); mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); local_bh_enable(); return true; But that's not the case: lock_sock_fast() is an interesting optimization for short critical sections which can run with bottom halves disabled and sock::sk_lock.slock held. This allows to shortcut the 'mutex' operation in the non contended case by preventing other lockers to acquire sock::sk_lock.owned because they are blocked on sock::sk_lock.slock, which in turn avoids the overhead of doing the heavy processing in release_sock() including waking up wait queue waiters. In the contended case, i.e. when sock::sk_lock.owned == true the behavior is the same as lock_sock_nested(). Semantically this shortcut means, that the task acquired the 'mutex' even if it does not touch the sock::sk_lock.owned field in the non-contended case. Not telling lockdep about this shortcut acquisition is hiding potential lock ordering violations in the fast path. As a consequence the same reasoning as for the above lock_sock_nested() case vs. the placement of the lockdep annotation applies. The current placement of the lockdep annotation was just copied from the original lock_sock(), now renamed to lock_sock_nested(), implementation. Fix this by moving the mutex_acquire() in front of the actual lock acquisition and adding the corresponding mutex_release() into unlock_sock_fast(). Also document the fast path return case with a comment. Reported-by: Sebastian Siewior <bigeasy@linutronix.de> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: netdev@vger.kernel.org Cc: "David S. Miller" <davem@davemloft.net> Cc: Jakub Kicinski <kuba@kernel.org> Cc: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sock: remove one redundant SKB_FRAG_PAGE_ORDER macroYunsheng Lin2021-08-261-1/+0
| | | | | | | | | | | | | Both SKB_FRAG_PAGE_ORDER are defined to the same value in net/core/sock.c and drivers/vhost/net.c. Move the SKB_FRAG_PAGE_ORDER definition to net/core/sock.h, as both net/core/sock.c and drivers/vhost/net.c include it, and it seems a reasonable file to put the macro. Signed-off-by: Yunsheng Lin <linyunsheng@huawei.com> Acked-by: Jason Wang <jasowang@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* net-memcg: pass in gfp_t mask to mem_cgroup_charge_skmem()Wei Wang2021-08-181-4/+12
| | | | | | | | | | | | | | | | Add gfp_t mask as an input parameter to mem_cgroup_charge_skmem(), to give more control to the networking stack and enable it to change memcg charging behavior. In the future, the networking stack may decide to avoid oom-kills when fallbacks are more appropriate. One behavior change in mem_cgroup_charge_skmem() by this patch is to avoid force charging by default and let the caller decide when and if force charging is needed through the presence or absence of __GFP_NOFAIL. Signed-off-by: Wei Wang <weiwan@google.com> Reviewed-by: Shakeel Butt <shakeelb@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sock: allow reading and changing sk_userlocks with setsockoptPavel Tikhomirov2021-08-041-0/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | SOCK_SNDBUF_LOCK and SOCK_RCVBUF_LOCK flags disable automatic socket buffers adjustment done by kernel (see tcp_fixup_rcvbuf() and tcp_sndbuf_expand()). If we've just created a new socket this adjustment is enabled on it, but if one changes the socket buffer size by setsockopt(SO_{SND,RCV}BUF*) it becomes disabled. CRIU needs to call setsockopt(SO_{SND,RCV}BUF*) on each socket on restore as it first needs to increase buffer sizes for packet queues restore and second it needs to restore back original buffer sizes. So after CRIU restore all sockets become non-auto-adjustable, which can decrease network performance of restored applications significantly. CRIU need to be able to restore sockets with enabled/disabled adjustment to the same state it was before dump, so let's add special setsockopt for it. Let's also export SOCK_SNDBUF_LOCK and SOCK_RCVBUF_LOCK flags to uAPI so that using these interface one can reenable automatic socket buffer adjustment on their sockets. Signed-off-by: Pavel Tikhomirov <ptikhomirov@virtuozzo.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* mctp: Add MCTP baseJeremy Kerr2021-07-291-0/+1
| | | | | | | | | Add basic Kconfig, an initial (empty) af_mctp source object, and {AF,PF}_MCTP definitions, and the required definitions for a new protocol type. Signed-off-by: Jeremy Kerr <jk@codeconstruct.com.au> Signed-off-by: David S. Miller <davem@davemloft.net>
* sock: unlock on error in sock_setsockopt()Dan Carpenter2021-07-071-2/+4
| | | | | | | | If copy_from_sockptr() then we need to unlock before returning. Fixes: d463126e23f1 ("net: sock: extend SO_TIMESTAMPING for PHC binding") Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by: David S. Miller <davem@davemloft.net>
* sock: fix error in sock_setsockopt()Eric Dumazet2021-07-021-1/+1
| | | | | | | | | | | | | | | | | | | Some tests are failing, John bisected the issue to a recent commit. sock_set_timestamp() parameters should be : 1) sk 2) optname 3) valbool Fixes: 371087aa476a ("sock: expose so_timestamp options for mptcp") Signed-off-by: Eric Dumazet <edumazet@google.com> Bisected-by: John Sperbeck <jsperbeck@google.com> Cc: Paolo Abeni <pabeni@redhat.com> Cc: Florian Westphal <fw@strlen.de> Cc: Mat Martineau <mathew.j.martineau@linux.intel.com> Reviewed-by: Florian Westphal <fw@strlen.de> Signed-off-by: David S. Miller <davem@davemloft.net>
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