scsi: lpfc: Don't release final kref on Fport node while ABTS outstanding
authorJames Smart <jsmart2021@gmail.com>
Fri, 10 Sep 2021 23:31:47 +0000 (16:31 -0700)
committerMartin K. Petersen <martin.petersen@oracle.com>
Wed, 15 Sep 2021 03:33:20 +0000 (23:33 -0400)
commit982fc3965d1350d3332e04046b0e101006184ba9
treebd21d7fe5441718b15fabd7739e53d9eaa17cce9
parent99154581b05c8fb22607afb7c3d66c1bace6aa5d
scsi: lpfc: Don't release final kref on Fport node while ABTS outstanding

In a rarely executed path, FLOGI failure, there is a refcounting error.  If
FLOGI completed with an error, typically a timeout, the initial completion
handler would remove the job reference. However, the job completion isn't
the actual end of the job/exchange as the timeout usually initiates an
ABTS, and upon that ABTS completion, a final completion is sent. The driver
removes the reference again in the final completion. Thus the imbalance.

In the buggy cases, if there was a link bounce while the delayed response
is outstanding, the fport node may be referenced again but there was no
additional reference as it is already present. The delayed completion then
occurs and removes the last reference freeing the node and causing issues
in the link up processed that is using the node.

Fix this scenario by removing the snippet that removed the reference in the
initial FLOGI completion. The bad snippet was poorly trying to identify the
FLOGI as OK to do so by realizing the node was not registered with either
SCSI or NVMe transport.

Link: https://lore.kernel.org/r/20210910233159.115896-3-jsmart2021@gmail.com
Fixes: 618e2ee146d4 ("scsi: lpfc: Fix FLOGI failure due to accessing a freed node")
Cc: <stable@vger.kernel.org> # v5.13+
Co-developed-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: Justin Tee <justin.tee@broadcom.com>
Signed-off-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/scsi/lpfc/lpfc_els.c
drivers/scsi/lpfc/lpfc_hbadisc.c
drivers/scsi/lpfc/lpfc_nvme.c