[PATCH] RDMA/cma: Fix listener leak in rdma_cma_listen_on_all() failure

From: Tao Liu
Date: Mon Sep 13 2021 - 05:41:31 EST


rdma_cma_listen_on_all() just destroy listener which lead to an error,
but not including those already added in listen_list. Then cm state
fallbacks to RDMA_CM_ADDR_BOUND.

When user destroys id, the listeners will not be destroyed, and
process stucks.

task:rping state:D stack: 0 pid:19605 ppid: 47036 flags:0x00000084
Call Trace:
__schedule+0x29a/0x780
? free_unref_page_commit+0x9b/0x110
schedule+0x3c/0xa0
schedule_timeout+0x215/0x2b0
? __flush_work+0x19e/0x1e0
wait_for_completion+0x8d/0xf0
_destroy_id+0x144/0x210 [rdma_cm]
ucma_close_id+0x2b/0x40 [rdma_ucm]
__destroy_id+0x93/0x2c0 [rdma_ucm]
? __xa_erase+0x4a/0xa0
ucma_destroy_id+0x9a/0x120 [rdma_ucm]
ucma_write+0xb8/0x130 [rdma_ucm]
vfs_write+0xb4/0x250
ksys_write+0xb5/0xd0
? syscall_trace_enter.isra.19+0x123/0x190
do_syscall_64+0x33/0x40
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Fixes: c80a0c52d85c ("RDMA/cma: Add missing error handling of listen_id")
Signed-off-by: Tao Liu <thomas.liu@xxxxxxxxx>
---
drivers/infiniband/core/cma.c | 22 +++++++++++++++-------
1 file changed, 15 insertions(+), 7 deletions(-)

diff --git a/drivers/infiniband/core/cma.c b/drivers/infiniband/core/cma.c
index c40791b..d8cea33 100644
--- a/drivers/infiniband/core/cma.c
+++ b/drivers/infiniband/core/cma.c
@@ -1746,16 +1746,11 @@ static void cma_cancel_route(struct rdma_id_private *id_priv)
}
}

-static void cma_cancel_listens(struct rdma_id_private *id_priv)
+static void _cma_cancel_listens(struct rdma_id_private *id_priv)
{
struct rdma_id_private *dev_id_priv;

- /*
- * Remove from listen_any_list to prevent added devices from spawning
- * additional listen requests.
- */
- mutex_lock(&lock);
- list_del(&id_priv->list);
+ lockdep_assert_held(&lock);

while (!list_empty(&id_priv->listen_list)) {
dev_id_priv = list_entry(id_priv->listen_list.next,
@@ -1768,6 +1763,18 @@ static void cma_cancel_listens(struct rdma_id_private *id_priv)
rdma_destroy_id(&dev_id_priv->id);
mutex_lock(&lock);
}
+}
+
+static void cma_cancel_listens(struct rdma_id_private *id_priv)
+{
+ /*
+ * Remove from listen_any_list to prevent added devices from spawning
+ * additional listen requests.
+ */
+ mutex_lock(&lock);
+ list_del(&id_priv->list);
+
+ _cma_cancel_listens(id_priv);
mutex_unlock(&lock);
}

@@ -2575,6 +2582,7 @@ static int cma_listen_on_all(struct rdma_id_private *id_priv)

err_listen:
list_del(&id_priv->list);
+ _cma_cancel_listens(id_priv);
mutex_unlock(&lock);
if (to_destroy)
rdma_destroy_id(&to_destroy->id);
--
1.8.3.1