From: Jason Gunthorpe <jgg@xxxxxxxxxx> [ Upstream commit 38e03d092699891c3237b5aee9e8029d4ede0956 ] All entry points to the rdma_cm from a ULP must be single threaded, even this error unwinds. Add the missing locking. Fixes: 7c11910783a1 ("RDMA/ucma: Put a lock around every call to the rdma_cm layer") Link: https://lore.kernel.org/r/20200818120526.702120-11-leon@xxxxxxxxxx Signed-off-by: Leon Romanovsky <leonro@xxxxxxxxxxxx> Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/infiniband/core/ucma.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/infiniband/core/ucma.c b/drivers/infiniband/core/ucma.c index cf283b70bf877..2643d5dbe1da8 100644 --- a/drivers/infiniband/core/ucma.c +++ b/drivers/infiniband/core/ucma.c @@ -1512,7 +1512,9 @@ static ssize_t ucma_process_join(struct ucma_file *file, return 0; err3: + mutex_lock(&ctx->mutex); rdma_leave_multicast(ctx->cm_id, (struct sockaddr *) &mc->addr); + mutex_unlock(&ctx->mutex); ucma_cleanup_mc_events(mc); err2: xa_erase(&multicast_table, mc->id); -- 2.25.1