From: Chad Dupuis <cdupuis@xxxxxxxxxxx> [ Upstream commit ad40f5256095c68dc17c991eb976261d5ea2daaa ] The MFW may make a call to qed and then to qedf for protocol statistics while the function is still probing. If this happens it's possible that some members of the struct qedf_ctx may not be fully initialized which can result in a NULL pointer dereference or general protection fault. To prevent this, add a new flag call QEDF_PROBING and set it when the __qedf_probe() function is active. Then in the qedf_get_protocol_tlv_data() function we can check if the function is still probing and return immediantely before any uninitialized structures can be touched. Link: https://lore.kernel.org/r/20200416084314.18851-9-skashyap@xxxxxxxxxxx Signed-off-by: Chad Dupuis <cdupuis@xxxxxxxxxxx> Signed-off-by: Saurav Kashyap <skashyap@xxxxxxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/scsi/qedf/qedf.h | 1 + drivers/scsi/qedf/qedf_main.c | 35 +++++++++++++++++++++++++++++++---- 2 files changed, 32 insertions(+), 4 deletions(-) diff --git a/drivers/scsi/qedf/qedf.h b/drivers/scsi/qedf/qedf.h index f3f399fe10c8..0da4e16fb23a 100644 --- a/drivers/scsi/qedf/qedf.h +++ b/drivers/scsi/qedf/qedf.h @@ -355,6 +355,7 @@ struct qedf_ctx { #define QEDF_GRCDUMP_CAPTURE 4 #define QEDF_IN_RECOVERY 5 #define QEDF_DBG_STOP_IO 6 +#define QEDF_PROBING 8 unsigned long flags; /* Miscellaneous state flags */ int fipvlan_retries; u8 num_queues; diff --git a/drivers/scsi/qedf/qedf_main.c b/drivers/scsi/qedf/qedf_main.c index 59ca98f12afd..3d0e345947c1 100644 --- a/drivers/scsi/qedf/qedf_main.c +++ b/drivers/scsi/qedf/qedf_main.c @@ -3153,7 +3153,7 @@ static int __qedf_probe(struct pci_dev *pdev, int mode) { int rc = -EINVAL; struct fc_lport *lport; - struct qedf_ctx *qedf; + struct qedf_ctx *qedf = NULL; struct Scsi_Host *host; bool is_vf = false; struct qed_ll2_params params; @@ -3183,6 +3183,7 @@ static int __qedf_probe(struct pci_dev *pdev, int mode) /* Initialize qedf_ctx */ qedf = lport_priv(lport); + set_bit(QEDF_PROBING, &qedf->flags); qedf->lport = lport; qedf->ctlr.lp = lport; qedf->pdev = pdev; @@ -3206,9 +3207,12 @@ static int __qedf_probe(struct pci_dev *pdev, int mode) } else { /* Init pointers during recovery */ qedf = pci_get_drvdata(pdev); + set_bit(QEDF_PROBING, &qedf->flags); lport = qedf->lport; } + QEDF_INFO(&qedf->dbg_ctx, QEDF_LOG_DISC, "Probe started.\n"); + host = lport->host; /* Allocate mempool for qedf_io_work structs */ @@ -3513,6 +3517,10 @@ static int __qedf_probe(struct pci_dev *pdev, int mode) else fc_fabric_login(lport); + QEDF_INFO(&qedf->dbg_ctx, QEDF_LOG_DISC, "Probe done.\n"); + + clear_bit(QEDF_PROBING, &qedf->flags); + /* All good */ return 0; @@ -3538,6 +3546,11 @@ static int __qedf_probe(struct pci_dev *pdev, int mode) err1: scsi_host_put(lport->host); err0: + if (qedf) { + QEDF_INFO(&qedf->dbg_ctx, QEDF_LOG_DISC, "Probe done.\n"); + + clear_bit(QEDF_PROBING, &qedf->flags); + } return rc; } @@ -3687,11 +3700,25 @@ void qedf_get_protocol_tlv_data(void *dev, void *data) { struct qedf_ctx *qedf = dev; struct qed_mfw_tlv_fcoe *fcoe = data; - struct fc_lport *lport = qedf->lport; - struct Scsi_Host *host = lport->host; - struct fc_host_attrs *fc_host = shost_to_fc_host(host); + struct fc_lport *lport; + struct Scsi_Host *host; + struct fc_host_attrs *fc_host; struct fc_host_statistics *hst; + if (!qedf) { + QEDF_ERR(NULL, "qedf is null.\n"); + return; + } + + if (test_bit(QEDF_PROBING, &qedf->flags)) { + QEDF_ERR(&qedf->dbg_ctx, "Function is still probing.\n"); + return; + } + + lport = qedf->lport; + host = lport->host; + fc_host = shost_to_fc_host(host); + /* Force a refresh of the fc_host stats including offload stats */ hst = qedf_fc_get_host_stats(host); -- 2.25.1
