From: Javed Hasan Date: Mon, 22 Jun 2020 10:12:11 +0000 (-0700) Subject: scsi: libfc: Handling of extra kref X-Git-Tag: v5.10.7~2072^2~9 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=71f2bf85e90d938d4a9ef9dd9bfa8d9b0b6a03f7;p=platform%2Fkernel%2Flinux-rpi.git scsi: libfc: Handling of extra kref 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 Reviewed-by: Saurav Kashyap Reviewed-by: Shyam Sundar Signed-off-by: Javed Hasan Signed-off-by: Martin K. Petersen --- diff --git a/drivers/scsi/libfc/fc_rport.c b/drivers/scsi/libfc/fc_rport.c index 773c45a..67eae8b 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;