diff options
author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2022-05-05 10:53:53 +0900 |
---|---|---|
committer | Jakub Kicinski <kuba@kernel.org> | 2022-05-05 16:44:49 -0700 |
commit | 6997fbd7a3dafa754f81d541498ace35b43246d8 (patch) | |
tree | 9903b4be70449cb3b8759040ed1b57bdf4d89ed4 /net/rds/tcp.h | |
parent | 68533eb1fb197a413fd8612ebb88e111ade3beac (diff) |
net: rds: use maybe_get_net() when acquiring refcount on TCP sockets
Eric Dumazet is reporting addition on 0 problem at rds_tcp_tune(), for
delayed works queued in rds_wq might be invoked after a net namespace's
refcount already reached 0.
Since rds_tcp_exit_net() from cleanup_net() calls flush_workqueue(rds_wq),
it is guaranteed that we can instead use maybe_get_net() from delayed work
functions until rds_tcp_exit_net() returns.
Note that I'm not convinced that all works which might access a net
namespace are already queued in rds_wq by the moment rds_tcp_exit_net()
calls flush_workqueue(rds_wq). If some race is there, rds_tcp_exit_net()
will fail to wait for work functions, and kmem_cache_free() could be
called from net_free() before maybe_get_net() is called from
rds_tcp_tune().
Reported-by: Eric Dumazet <edumazet@google.com>
Fixes: 3a58f13a881ed351 ("net: rds: acquire refcount on TCP sockets")
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/41d09faf-bc78-1a87-dfd1-c6d1b5984b61@I-love.SAKURA.ne.jp
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/rds/tcp.h')
-rw-r--r-- | net/rds/tcp.h | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/rds/tcp.h b/net/rds/tcp.h index dc8d745d6857..f8b5930d7b34 100644 --- a/net/rds/tcp.h +++ b/net/rds/tcp.h @@ -49,7 +49,7 @@ struct rds_tcp_statistics { }; /* tcp.c */ -void rds_tcp_tune(struct socket *sock); +bool rds_tcp_tune(struct socket *sock); void rds_tcp_set_callbacks(struct socket *sock, struct rds_conn_path *cp); void rds_tcp_reset_callbacks(struct socket *sock, struct rds_conn_path *cp); void rds_tcp_restore_callbacks(struct socket *sock, |