linux-stable.git/net/tipc/socket.c, branch linux-4.9.y

net: tipc: fix possible refcount leak in tipc_sk_create()

2022-07-21T18:40:32+00:00

[ Upstream commit 00aff3590fc0a73bddd3b743863c14e76fd35c0c ]

Free sk in case tipc_sk_insert() fails.

Signed-off-by: Hangyu Hua 
Reviewed-by: Tung Nguyen 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

tipc: increase timeout in tipc_sk_enqueue()

2021-09-22T09:43:09+00:00

commit f4bb62e64c88c93060c051195d3bbba804e56945 upstream.

In tipc_sk_enqueue() we use hardcoded 2 jiffies to extract
socket buffer from generic queue to particular socket.
The 2 jiffies is too short in case there are other high priority
tasks get CPU cycles for multiple jiffies update. As result, no
buffer could be enqueued to particular socket.

To solve this, we switch to use constant timeout 20msecs.
Then, the function will be expired between 2 jiffies (CONFIG_100HZ)
and 20 jiffies (CONFIG_1000HZ).

Fixes: c637c1035534 ("tipc: resolve race problem at unicast message reception")
Acked-by: Jon Maloy 
Signed-off-by: Hoang Le 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tipc: fix sleeping in tipc accept routine

2021-08-04T09:58:03+00:00

[ Upstream commit d237a7f11719ff9320721be5818352e48071aab6 ]

The release_sock() is blocking function, it would change the state
after sleeping. In order to evaluate the stated condition outside
the socket lock context, switch to use wait_woken() instead.

Fixes: 6398e23cdb1d8 ("tipc: standardize accept routine")
Acked-by: Jon Maloy 
Signed-off-by: Hoang Le 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

Revert "net:tipc: Fix a double free in tipc_sk_mcast_rcv"

2021-06-03T06:23:30+00:00

commit 75016891357a628d2b8acc09e2b9b2576c18d318 upstream.

This reverts commit 6bf24dc0cc0cc43b29ba344b66d78590e687e046.
Above fix is not correct and caused memory leak issue.

Fixes: 6bf24dc0cc0c ("net:tipc: Fix a double free in tipc_sk_mcast_rcv")
Acked-by: Jon Maloy 
Acked-by: Tung Nguyen 
Signed-off-by: Hoang Le 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

net:tipc: Fix a double free in tipc_sk_mcast_rcv

2021-04-16T09:59:08+00:00

[ Upstream commit 6bf24dc0cc0cc43b29ba344b66d78590e687e046 ]

In the if(skb_peek(arrvq) == skb) branch, it calls __skb_dequeue(arrvq) to get
the skb by skb = skb_peek(arrvq). Then __skb_dequeue() unlinks the skb from arrvq
and returns the skb which equals to skb_peek(arrvq). After __skb_dequeue(arrvq)
finished, the skb is freed by kfree_skb(__skb_dequeue(arrvq)) in the first time.

Unfortunately, the same skb is freed in the second time by kfree_skb(skb) after
the branch completed.

My patch removes kfree_skb() in the if(skb_peek(arrvq) == skb) branch, because
this skb will be freed by kfree_skb(skb) finally.

Fixes: cb1b728096f54 ("tipc: eliminate race condition at multicast reception")
Signed-off-by: Lv Yunlong 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

tipc: use lock_sock() in tipc_sk_reinit()

2019-01-09T15:16:41+00:00

[ Upstream commit 15ef70e286176165d28b0b8a969b422561a68dfc ]

lock_sock() must be used in process context to be race-free with
other lock_sock() callers, for example, tipc_release(). Otherwise
using the spinlock directly can't serialize a parallel tipc_release().

As it is blocking, we have to hold the sock refcnt before
rhashtable_walk_stop() and release it after rhashtable_walk_start().

Fixes: 07f6c4bc048a ("tipc: convert tipc reference table to use generic rhashtable")
Reported-by: Dmitry Vyukov 
Cc: Ying Xue 
Cc: Jon Maloy 
Signed-off-by: Cong Wang 
Signed-off-by: David S. Miller 
Signed-off-by: Greg Kroah-Hartman

tipc: Fix tipc_sk_reinit handling of -EAGAIN

2018-11-10T15:42:46+00:00

[ Upstream commit 6c7e983b220f89e03286dc70a41c7ef3a8b409df ]

In 9dbbfb0ab6680c6a85609041011484e6658e7d3c function tipc_sk_reinit
had additional logic added to loop in the event that function
rhashtable_walk_next() returned -EAGAIN. No worries.

However, if rhashtable_walk_start returns -EAGAIN, it does "continue",
and therefore skips the call to rhashtable_walk_stop(). That has
the effect of calling rcu_read_lock() without its paired call to
rcu_read_unlock(). Since rcu_read_lock() may be nested, the problem
may not be apparent for a while, especially since resize events may
be rare. But the comments to rhashtable_walk_start() state:

 * ...Note that we take the RCU lock in all
 * cases including when we return an error.  So you must always call
 * rhashtable_walk_stop to clean up.

This patch replaces the continue with a goto and label to ensure a
matching call to rhashtable_walk_stop().

Signed-off-by: Bob Peterson 
Acked-by: Herbert Xu 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin

tipc: Fix tipc_sk_reinit race conditions

2017-06-17T04:41:49+00:00

[ Upstream commit 9dbbfb0ab6680c6a85609041011484e6658e7d3c ]

There are two problems with the function tipc_sk_reinit.  Firstly
it's doing a manual walk over an rhashtable.  This is broken as
an rhashtable can be resized and if you manually walk over it
during a resize then you may miss entries.

Secondly it's missing memory barriers as previously the code used
spinlocks which provide the barriers implicitly.

This patch fixes both problems.

Fixes: 07f6c4bc048a ("tipc: convert tipc reference table to...")
Signed-off-by: Herbert Xu 
Acked-by: Ying Xue 
Signed-off-by: David S. Miller 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

tipc: resolve connection flow control compatibility problem

2016-11-26T02:38:16+00:00

In commit 10724cc7bb78 ("tipc: redesign connection-level flow control")
we replaced the previous message based flow control with one based on
1k blocks. In order to ensure backwards compatibility the mechanism
falls back to using message as base unit when it senses that the peer
doesn't support the new algorithm. The default flow control window,
i.e., how many units can be sent before the sender blocks and waits
for an acknowledge (aka advertisement) is 512. This was tested against
the previous version, which uses an acknowledge frequency of on ack per
256 received message, and found to work fine.

However, we missed the fact that versions older than Linux 3.15 use an
acknowledge frequency of 512, which is exactly the limit where a 4.6+
sender will stop and wait for acknowledge. This would also work fine if
it weren't for the fact that if the first sent message on a 4.6+ server
side is an empty SYNACK, this one is also is counted as a sent message,
while it is not counted as a received message on a legacy 3.15-receiver.
This leads to the sender always being one step ahead of the receiver, a
scenario causing the sender to block after 512 sent messages, while the
receiver only has registered 511 read messages. Hence, the legacy
receiver is not trigged to send an acknowledge, with a permanently
blocked sender as result.

We solve this deadlock by simply allowing the sender to send one more
message before it blocks, i.e., by a making minimal change to the
condition used for determining connection congestion.

Signed-off-by: Jon Maloy 
Signed-off-by: David S. Miller

tipc: eliminate obsolete socket locking policy description

2016-11-20T03:15:41+00:00

The comment block in socket.c describing the locking policy is
obsolete, and does not reflect current reality. We remove it in this
commit.

Since the current locking policy is much simpler and follows a
mainstream approach, we see no need to add a new description.

Signed-off-by: Jon Maloy 
Signed-off-by: David S. Miller