diff options
| author | Karsten Graul <kgraul@linux.ibm.com> | 2019-01-30 18:51:02 +0100 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-12-05 15:37:57 +0100 |
| commit | bbd45bd490f0a71a59c364d6fc664c1086771721 (patch) | |
| tree | eec8f9a27ea2cd390318921f8f9008560fc1dfc8 /net | |
| parent | b89c62555ab774d816c7b3d341cfb9f3b27c7a59 (diff) | |
net/smc: prevent races between smc_lgr_terminate() and smc_conn_free()
[ Upstream commit 77f838ace755d2f466536c44dac6c856f62cd901 ]
To prevent races between smc_lgr_terminate() and smc_conn_free() add an
extra check of the lgr field before accessing it, and cancel a delayed
free_work when a new smc connection is created.
This fixes the problem that free_work cleared the lgr variable but
smc_lgr_terminate() or smc_conn_free() still access it in parallel.
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Ursula Braun <ubraun@linux.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/smc/smc_core.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index f04a037dc967..0de788fa43e9 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -103,6 +103,8 @@ static void smc_lgr_unregister_conn(struct smc_connection *conn) struct smc_link_group *lgr = conn->lgr; int reduced = 0; + if (!lgr) + return; write_lock_bh(&lgr->conns_lock); if (conn->alert_token_local) { reduced = 1; @@ -431,6 +433,8 @@ int smc_conn_create(struct smc_sock *smc, __be32 peer_in_addr, local_contact = SMC_REUSE_CONTACT; conn->lgr = lgr; smc_lgr_register_conn(conn); /* add smc conn to lgr */ + if (delayed_work_pending(&lgr->free_work)) + cancel_delayed_work(&lgr->free_work); write_unlock_bh(&lgr->conns_lock); break; } |