[PATCH 5.12 385/700] RDMA/rtrs-srv: Fix memory leak of unfreed rtrs_srv_stats object
From: Greg Kroah-Hartman
Date: Mon Jul 12 2021 - 03:45:39 EST
From: Gioh Kim <gi-oh.kim@xxxxxxxxxxxxxxx>
[ Upstream commit 2371c40354509746e4a4dad09a752e027a30f148 ]
When closing a session, currently the rtrs_srv_stats object in the
closing session is freed by kobject release. But if it failed
to create a session by various reasons, it must free the rtrs_srv_stats
object directly because kobject is not created yet.
This problem is found by kmemleak as below:
1. One client machine maps /dev/nullb0 with session name 'bla':
root@test1:~# echo "sessname=bla path=ip:192.168.122.190 \
device_path=/dev/nullb0" > /sys/devices/virtual/rnbd-client/ctl/map_device
2. Another machine failed to create a session with the same name 'bla':
root@test2:~# echo "sessname=bla path=ip:192.168.122.190 \
device_path=/dev/nullb1" > /sys/devices/virtual/rnbd-client/ctl/map_device
-bash: echo: write error: Connection reset by peer
3. The kmemleak on server machine reported an error:
unreferenced object 0xffff888033cdc800 (size 128):
comm "kworker/2:1", pid 83, jiffies 4295086585 (age 2508.680s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000a72903b2>] __alloc_sess+0x1d4/0x1250 [rtrs_server]
[<00000000d1e5321e>] rtrs_srv_rdma_cm_handler+0xc31/0xde0 [rtrs_server]
[<00000000bb2f6e7e>] cma_ib_req_handler+0xdc5/0x2b50 [rdma_cm]
[<00000000e896235d>] cm_process_work+0x2d/0x100 [ib_cm]
[<00000000b6866c5f>] cm_req_handler+0x11bc/0x1c40 [ib_cm]
[<000000005f5dd9aa>] cm_work_handler+0xe65/0x3cf2 [ib_cm]
[<00000000610151e7>] process_one_work+0x4bc/0x980
[<00000000541e0f77>] worker_thread+0x78/0x5c0
[<00000000423898ca>] kthread+0x191/0x1e0
[<000000005a24b239>] ret_from_fork+0x3a/0x50
Fixes: 39c2d639ca183 ("RDMA/rtrs-srv: Set .release function for rtrs srv device during device init")
Link: https://lore.kernel.org/r/20210528113018.52290-18-jinpu.wang@xxxxxxxxx
Signed-off-by: Gioh Kim <gi-oh.kim@xxxxxxxxx>
Signed-off-by: Md Haris Iqbal <haris.iqbal@xxxxxxxxx>
Signed-off-by: Jack Wang <jinpu.wang@xxxxxxxxx>
Signed-off-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/infiniband/ulp/rtrs/rtrs-srv.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/drivers/infiniband/ulp/rtrs/rtrs-srv.c b/drivers/infiniband/ulp/rtrs/rtrs-srv.c
index d071809e3ed2..8c0acfc48392 100644
--- a/drivers/infiniband/ulp/rtrs/rtrs-srv.c
+++ b/drivers/infiniband/ulp/rtrs/rtrs-srv.c
@@ -1477,6 +1477,7 @@ static void free_sess(struct rtrs_srv_sess *sess)
kobject_del(&sess->kobj);
kobject_put(&sess->kobj);
} else {
+ kfree(sess->stats);
kfree(sess);
}
}
--
2.30.2