diff options
author | Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> | 2022-05-05 04:53:53 +0300 |
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committer | Jakub Kicinski <kuba@kernel.org> | 2022-05-06 02:44:49 +0300 |
commit | 6997fbd7a3dafa754f81d541498ace35b43246d8 (patch) | |
tree | 9903b4be70449cb3b8759040ed1b57bdf4d89ed4 /net/rds/tcp_listen.c | |
parent | 68533eb1fb197a413fd8612ebb88e111ade3beac (diff) | |
download | linux-6997fbd7a3dafa754f81d541498ace35b43246d8.tar.xz |
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_listen.c')
-rw-r--r-- | net/rds/tcp_listen.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/net/rds/tcp_listen.c b/net/rds/tcp_listen.c index 09cadd556d1e..7edf2e69d3fe 100644 --- a/net/rds/tcp_listen.c +++ b/net/rds/tcp_listen.c @@ -133,7 +133,10 @@ int rds_tcp_accept_one(struct socket *sock) __module_get(new_sock->ops->owner); rds_tcp_keepalive(new_sock); - rds_tcp_tune(new_sock); + if (!rds_tcp_tune(new_sock)) { + ret = -EINVAL; + goto out; + } inet = inet_sk(new_sock->sk); |