From 3739707c4568f05842c8bf770285328067bd6679 Mon Sep 17 00:00:00 2001 From: Karsten Graul Date: Mon, 17 Feb 2020 16:24:52 +0100 Subject: [PATCH] net/smc: do not delete lgr from list twice When 2 callers call smc_lgr_terminate() at the same time for the same lgr, one gets the lgr_lock and deletes the lgr from the list and releases the lock. Then the second caller gets the lock and tries to delete it again. In smc_lgr_terminate() add a check if the link group lgr is already deleted from the link group list and prevent to try to delete it a second time. And add a check if the lgr is marked as freeing, which means that a termination is already pending. Signed-off-by: Karsten Graul Signed-off-by: Ursula Braun Signed-off-by: David S. Miller --- net/smc/smc_core.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index 8f3c1fced334..9b92b52952dd 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -629,7 +629,7 @@ void smc_lgr_terminate(struct smc_link_group *lgr, bool soft) smc_lgr_list_head(lgr, &lgr_lock); spin_lock_bh(lgr_lock); - if (lgr->terminating) { + if (list_empty(&lgr->list) || lgr->terminating || lgr->freeing) { spin_unlock_bh(lgr_lock); return; /* lgr already terminating */ }