From: Javed Hasan jhasan@marvell.com
[ Upstream commit 71f2bf85e90d938d4a9ef9dd9bfa8d9b0b6a03f7 ]
Handling of extra kref which is done by lookup table in case rdata is already present in list.
This issue was leading to memory leak. Trace from KMEMLEAK tool:
unreferenced object 0xffff8888259e8780 (size 512): comm "kworker/2:1", pid 182614, jiffies 4433237386 (age 113021.971s) hex dump (first 32 bytes): 58 0a ec cf 83 88 ff ff 00 00 00 00 00 00 00 00 01 00 00 00 08 00 00 00 13 7d f0 1e 0e 00 00 10 backtrace: [<000000006b25760f>] fc_rport_recv_req+0x3c6/0x18f0 [libfc] [<00000000f208d994>] fc_lport_recv_els_req+0x120/0x8a0 [libfc] [<00000000a9c437b8>] fc_lport_recv+0xb9/0x130 [libfc] [<00000000ad5be37b>] qedf_ll2_process_skb+0x73d/0xad0 [qedf] [<00000000e0eb6893>] process_one_work+0x382/0x6c0 [<000000002dfd9e21>] worker_thread+0x57/0x5c0 [<00000000b648204f>] kthread+0x1a0/0x1c0 [<0000000072f5ab20>] ret_from_fork+0x35/0x40 [<000000001d5c05d8>] 0xffffffffffffffff
Below is the log sequence which leads to memory leak. Here we get the nested "Received PLOGI request" for same port and this request leads to call the fc_rport_create() twice for the same rport.
kernel: host1: rport fffce5: Received PLOGI request kernel: host1: rport fffce5: Received PLOGI in INIT state kernel: host1: rport fffce5: Port is Ready kernel: host1: rport fffce5: Received PRLI request while in state Ready kernel: host1: rport fffce5: PRLI rspp type 8 active 1 passive 0 kernel: host1: rport fffce5: Received LOGO request while in state Ready kernel: host1: rport fffce5: Delete port kernel: host1: rport fffce5: Received PLOGI request kernel: host1: rport fffce5: Received PLOGI in state Delete - send busy
Link: https://lore.kernel.org/r/20200622101212.3922-2-jhasan@marvell.com Reviewed-by: Girish Basrur gbasrur@marvell.com Reviewed-by: Saurav Kashyap skashyap@marvell.com Reviewed-by: Shyam Sundar ssundar@marvell.com Signed-off-by: Javed Hasan jhasan@marvell.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/libfc/fc_rport.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/drivers/scsi/libfc/fc_rport.c b/drivers/scsi/libfc/fc_rport.c index 6bb8917b99a19..aabf51df3c02f 100644 --- a/drivers/scsi/libfc/fc_rport.c +++ b/drivers/scsi/libfc/fc_rport.c @@ -133,8 +133,10 @@ struct fc_rport_priv *fc_rport_create(struct fc_lport *lport, u32 port_id) lockdep_assert_held(&lport->disc.disc_mutex);
rdata = fc_rport_lookup(lport, port_id); - if (rdata) + if (rdata) { + kref_put(&rdata->kref, fc_rport_destroy); return rdata; + }
if (lport->rport_priv_size > 0) rport_priv_size = lport->rport_priv_size;