release/5.2.27/cxgb4-fix-panic-when-attaching-to-ULD-fail.patch

From 11ccb2b93320436010e2269175eeae2c1ae011a0 Mon Sep 17 00:00:00 2001
From: Vishal Kulkarni <vishal@chelsio.com>
Date: Wed, 30 Oct 2019 20:17:57 +0530
Subject: [PATCH] cxgb4: fix panic when attaching to ULD fail

commit fc89cc358fb64e2429aeae0f37906126636507ec upstream.

Release resources when attaching to ULD fail. Otherwise, data
mismatch is seen between LLD and ULD later on, which lead to
kernel panic when accessing resources that should not even
exist in the first place.

Fixes: 94cdb8bb993a ("cxgb4: Add support for dynamic allocation of resources for ULD")
Signed-off-by: Shahjada Abul Husain <shahjada@chelsio.com>
Signed-off-by: Vishal Kulkarni <vishal@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>

diff --git a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c
index bf17cf3ef613..96d2b7806e28 100644
--- a/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c
+++ b/drivers/net/ethernet/chelsio/cxgb4/cxgb4_uld.c
@@ -686,10 +686,10 @@ static void uld_init(struct adapter *adap, struct cxgb4_lld_info *lld)
 	lld->write_cmpl_support = adap->params.write_cmpl_support;
 }
 
-static void uld_attach(struct adapter *adap, unsigned int uld)
+static int uld_attach(struct adapter *adap, unsigned int uld)
 {
-	void *handle;
 	struct cxgb4_lld_info lli;
+	void *handle;
 
 	uld_init(adap, &lli);
 	uld_queue_init(adap, uld, &lli);
@@ -699,7 +699,7 @@ static void uld_attach(struct adapter *adap, unsigned int uld)
 		dev_warn(adap->pdev_dev,
 			 "could not attach to the %s driver, error %ld\n",
 			 adap->uld[uld].name, PTR_ERR(handle));
-		return;
+		return PTR_ERR(handle);
 	}
 
 	adap->uld[uld].handle = handle;
@@ -707,22 +707,22 @@ static void uld_attach(struct adapter *adap, unsigned int uld)
 
 	if (adap->flags & CXGB4_FULL_INIT_DONE)
 		adap->uld[uld].state_change(handle, CXGB4_STATE_UP);
+
+	return 0;
 }
 
-/**
- *	cxgb4_register_uld - register an upper-layer driver
- *	@type: the ULD type
- *	@p: the ULD methods
+/* cxgb4_register_uld - register an upper-layer driver
+ * @type: the ULD type
+ * @p: the ULD methods
  *
- *	Registers an upper-layer driver with this driver and notifies the ULD
- *	about any presently available devices that support its type.  Returns
- *	%-EBUSY if a ULD of the same type is already registered.
+ * Registers an upper-layer driver with this driver and notifies the ULD
+ * about any presently available devices that support its type.
  */
 void cxgb4_register_uld(enum cxgb4_uld type,
 			const struct cxgb4_uld_info *p)
 {
-	int ret = 0;
 	struct adapter *adap;
+	int ret = 0;
 
 	if (type >= CXGB4_ULD_MAX)
 		return;
@@ -754,8 +754,12 @@ void cxgb4_register_uld(enum cxgb4_uld type,
 		if (ret)
 			goto free_irq;
 		adap->uld[type] = *p;
-		uld_attach(adap, type);
+		ret = uld_attach(adap, type);
+		if (ret)
+			goto free_txq;
 		continue;
+free_txq:
+		release_sge_txq_uld(adap, type);
 free_irq:
 		if (adap->flags & CXGB4_FULL_INIT_DONE)
 			quiesce_rx_uld(adap, type);
-- 
2.7.4