4.15-stable review patch. If anyone has any objections, please let me know.
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From: James Smart jsmart2021@gmail.com
[ Upstream commit 6fda20283e55b9d288cd56822ce39fc8e64f2208 ]
The current fcloop driver gets its lport structure from the private area co-allocated with the fc_localport. All is fine except the teardown path, which wants to wait on the completion, which is marked complete by the delete_localport callback performed after unregister_localport. The issue is, the nvme_fc transport frees the localport structure immediately after delete_localport is called, meaning the original routine is trying to wait on a complete that was just freed.
Change such that a lport struct is allocated coincident with the addition and registration of a localport. The private area of the localport now contains just a backpointer to the real lport struct. Now, the completion can be waited for, and after completing, the new structure can be kfree'd.
Signed-off-by: James Smart james.smart@broadcom.com Signed-off-by: Christoph Hellwig hch@lst.de Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/nvme/target/fcloop.c | 35 +++++++++++++++++++++++++---------- 1 file changed, 25 insertions(+), 10 deletions(-)
--- a/drivers/nvme/target/fcloop.c +++ b/drivers/nvme/target/fcloop.c @@ -204,6 +204,10 @@ struct fcloop_lport { struct completion unreg_done; };
+struct fcloop_lport_priv { + struct fcloop_lport *lport; +}; + struct fcloop_rport { struct nvme_fc_remote_port *remoteport; struct nvmet_fc_target_port *targetport; @@ -657,7 +661,8 @@ fcloop_nport_get(struct fcloop_nport *np static void fcloop_localport_delete(struct nvme_fc_local_port *localport) { - struct fcloop_lport *lport = localport->private; + struct fcloop_lport_priv *lport_priv = localport->private; + struct fcloop_lport *lport = lport_priv->lport;
/* release any threads waiting for the unreg to complete */ complete(&lport->unreg_done); @@ -697,7 +702,7 @@ static struct nvme_fc_port_template fcte .max_dif_sgl_segments = FCLOOP_SGL_SEGS, .dma_boundary = FCLOOP_DMABOUND_4G, /* sizes of additional private data for data structures */ - .local_priv_sz = sizeof(struct fcloop_lport), + .local_priv_sz = sizeof(struct fcloop_lport_priv), .remote_priv_sz = sizeof(struct fcloop_rport), .lsrqst_priv_sz = sizeof(struct fcloop_lsreq), .fcprqst_priv_sz = sizeof(struct fcloop_ini_fcpreq), @@ -728,11 +733,17 @@ fcloop_create_local_port(struct device * struct fcloop_ctrl_options *opts; struct nvme_fc_local_port *localport; struct fcloop_lport *lport; - int ret; + struct fcloop_lport_priv *lport_priv; + unsigned long flags; + int ret = -ENOMEM; + + lport = kzalloc(sizeof(*lport), GFP_KERNEL); + if (!lport) + return -ENOMEM;
opts = kzalloc(sizeof(*opts), GFP_KERNEL); if (!opts) - return -ENOMEM; + goto out_free_lport;
ret = fcloop_parse_options(opts, buf); if (ret) @@ -752,23 +763,25 @@ fcloop_create_local_port(struct device *
ret = nvme_fc_register_localport(&pinfo, &fctemplate, NULL, &localport); if (!ret) { - unsigned long flags; - /* success */ - lport = localport->private; + lport_priv = localport->private; + lport_priv->lport = lport; + lport->localport = localport; INIT_LIST_HEAD(&lport->lport_list);
spin_lock_irqsave(&fcloop_lock, flags); list_add_tail(&lport->lport_list, &fcloop_lports); spin_unlock_irqrestore(&fcloop_lock, flags); - - /* mark all of the input buffer consumed */ - ret = count; }
out_free_opts: kfree(opts); +out_free_lport: + /* free only if we're going to fail */ + if (ret) + kfree(lport); + return ret ? ret : count; }
@@ -790,6 +803,8 @@ __wait_localport_unreg(struct fcloop_lpo
wait_for_completion(&lport->unreg_done);
+ kfree(lport); + return ret; }