kernel/linux.git/net/core/sock.c, branch v4.9.331

net: Fix a data-race around sysctl_net_busy_read.

2022-09-05T08:23:55+00:00

[ Upstream commit e59ef36f0795696ab229569c153936bfd068d21c ] While reading sysctl_net_busy_read, it can be changed concurrently. Thus, we need to add READ_ONCE() to its reader. Fixes: 2d48d67fa8cd ("net: poll/select low latency socket support") Signed-off-by: Kuniyuki Iwashima Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

af_unix: fix races in sk_peer_pid and sk_peer_cred accesses

2021-10-09T11:25:58+00:00

commit 35306eb23814444bd4021f8a1c3047d3cb0c8b2b upstream. 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 Reported-by: Jann Horn Cc: Eric W. Biederman Cc: Luiz Augusto von Dentz Cc: Marcel Holtmann Signed-off-by: David S. Miller [backport note: 4.4 and 4.9 don't have SO_PEERGROUPS, only SO_PEERCRED] [backport note: got rid of sk_get_peer_cred(), no users in 4.4/4.9] Signed-off-by: Jann Horn Signed-off-by: Greg Kroah-Hartman

net/compat: Add missing sock updates for SCM_RIGHTS

2020-08-21T09:02:08+00:00

commit d9539752d23283db4692384a634034f451261e29 upstream. Add missed sock updates to compat path via a new helper, which will be used more in coming patches. (The net/core/scm.c code is left as-is here to assist with -stable backports for the compat path.) Cc: Christoph Hellwig Cc: Sargun Dhillon Cc: Jakub Kicinski Cc: stable@vger.kernel.org Fixes: 48a87cc26c13 ("net: netprio: fd passed in SCM_RIGHTS datagram not set correctly") Fixes: d84295067fc7 ("net: net_cls: fd passed in SCM_RIGHTS datagram not set correctly") Acked-by: Christian Brauner Signed-off-by: Kees Cook Signed-off-by: Greg Kroah-Hartman

cgroup: fix cgroup_sk_alloc() for sk_clone_lock()

2020-07-22T07:10:48+00:00

[ Upstream commit ad0f75e5f57ccbceec13274e1e242f2b5a6397ed ] When we clone a socket in sk_clone_lock(), its sk_cgrp_data is copied, so the cgroup refcnt must be taken too. And, unlike the sk_alloc() path, sock_update_netprioidx() is not called here. Therefore, it is safe and necessary to grab the cgroup refcnt even when cgroup_sk_alloc is disabled. sk_clone_lock() is in BH context anyway, the in_interrupt() would terminate this function if called there. And for sk_alloc() skcd->val is always zero. So it's safe to factor out the code to make it more readable. The global variable 'cgroup_sk_alloc_disabled' is used to determine whether to take these reference counts. It is impossible to make the reference counting correct unless we save this bit of information in skcd->val. So, add a new bit there to record whether the socket has already taken the reference counts. This obviously relies on kmalloc() to align cgroup pointers to at least 4 bytes, ARCH_KMALLOC_MINALIGN is certainly larger than that. This bug seems to be introduced since the beginning, commit d979a39d7242 ("cgroup: duplicate cgroup reference when cloning sockets") tried to fix it but not compeletely. It seems not easy to trigger until the recent commit 090e28b229af ("netprio_cgroup: Fix unlimited memory leak of v2 cgroups") was merged. Fixes: bd1060a1d671 ("sock, cgroup: add sock->sk_cgroup") Reported-by: Cameron Berkenpas Reported-by: Peter Geis Reported-by: Lu Fengqi Reported-by: Daniël Sonck Reported-by: Zhang Qiang Tested-by: Cameron Berkenpas Tested-by: Peter Geis Tested-by: Thomas Lamprecht Cc: Daniel Borkmann Cc: Zefan Li Cc: Tejun Heo Cc: Roman Gushchin Signed-off-by: Cong Wang Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: Do not clear the sock TX queue in sk_set_socket()

2020-06-30T19:38:39+00:00

[ Upstream commit 41b14fb8724d5a4b382a63cb4a1a61880347ccb8 ] Clearing the sock TX queue in sk_set_socket() might cause unexpected out-of-order transmit when called from sock_orphan(), as outstanding packets can pick a different TX queue and bypass the ones already queued. This is undesired in general. More specifically, it breaks the in-order scheduling property guarantee for device-offloaded TLS sockets. Remove the call to sk_tx_queue_clear() in sk_set_socket(), and add it explicitly only where needed. Fixes: e022f0b4a03f ("net: Introduce sk_tx_queue_mapping") Signed-off-by: Tariq Toukan Reviewed-by: Boris Pismenny Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: fix possible overflow in __sk_mem_raise_allocated()

2019-12-05T14:35:13+00:00

[ Upstream commit 5bf325a53202b8728cf7013b72688c46071e212e ] With many active TCP sockets, fat TCP sockets could fool __sk_mem_raise_allocated() thanks to an overflow. They would increase their share of the memory, instead of decreasing it. Signed-off-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

Revert "sock: Reset dst when changing sk_mark via setsockopt"

2019-11-29T08:31:24+00:00

This reverts commit 597b389bd8d496c050b7a02058702d27bf0ae3fa which is commit 50254256f382c56bde87d970f3d0d02fdb76ec70 upstream. It breaks a number of runtime Android networking tests, so something is wrong with the backport, or something else also needed to be backported at the same time. So I'm dropping this from the tree as regressions are not good. Cc: David Barmann Cc: Eric Dumazet Cc: David S. Miller Cc: Sasha Levin Signed-off-by: Greg Kroah-Hartman

sock: Reset dst when changing sk_mark via setsockopt

2019-11-28T17:29:01+00:00

[ Upstream commit 50254256f382c56bde87d970f3d0d02fdb76ec70 ] When setting the SO_MARK socket option, if the mark changes, the dst needs to be reset so that a new route lookup is performed. This fixes the case where an application wants to change routing by setting a new sk_mark. If this is done after some packets have already been sent, the dst is cached and has no effect. Signed-off-by: David Barmann Reviewed-by: Eric Dumazet Signed-off-by: David S. Miller Signed-off-by: Sasha Levin

net: Unpublish sk from sk_reuseport_cb before call_rcu

2019-10-07T16:53:21+00:00

[ Upstream commit 8c7138b33e5c690c308b2a7085f6313fdcb3f616 ] The "reuse->sock[]" array is shared by multiple sockets. The going away sk must unpublish itself from "reuse->sock[]" before making call_rcu() call. However, this unpublish-action is currently done after a grace period and it may cause use-after-free. The fix is to move reuseport_detach_sock() to sk_destruct(). Due to the above reason, any socket with sk_reuseport_cb has to go through the rcu grace period before freeing it. It is a rather old bug (~3 yrs). The Fixes tag is not necessary the right commit but it is the one that introduced the SOCK_RCU_FREE logic and this fix is depending on it. Fixes: a4298e4522d6 ("net: add SOCK_RCU_FREE socket flag") Cc: Eric Dumazet Suggested-by: Eric Dumazet Signed-off-by: Martin KaFai Lau Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman

net: call sk_dst_reset when set SO_DONTROUTE

2019-01-26T08:38:34+00:00

[ Upstream commit 0fbe82e628c817e292ff588cd5847fc935e025f2 ] after set SO_DONTROUTE to 1, the IP layer should not route packets if the dest IP address is not in link scope. But if the socket has cached the dst_entry, such packets would be routed until the sk_dst_cache expires. So we should clean the sk_dst_cache when a user set SO_DONTROUTE option. Below are server/client python scripts which could reprodue this issue: server side code: ========================================================================== import socket import struct import time s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.bind(('0.0.0.0', 9000)) s.listen(1) sock, addr = s.accept() sock.setsockopt(socket.SOL_SOCKET, socket.SO_DONTROUTE, struct.pack('i', 1)) while True: sock.send(b'foo') time.sleep(1) ========================================================================== client side code: ========================================================================== import socket import time s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.connect(('server_address', 9000)) while True: data = s.recv(1024) print(data) ========================================================================== Signed-off-by: yupeng Signed-off-by: David S. Miller Signed-off-by: Sasha Levin