[PATCH AUTOSEL 5.12 10/63] Revert "net/smc: fix a NULL pointer dereference"

[PATCH AUTOSEL 5.12 10/63] Revert "net/smc: fix a NULL pointer dereference"

[Sasha Levin]

From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

[ Upstream commit 5369ead83f5aff223b6418c99cb1fe9a8f007363 ]

This reverts commit e183d4e414b64711baf7a04e214b61969ca08dfa.

Because of recent interactions with developers from @umn.edu, all
commits from them have been recently re-reviewed to ensure if they were
correct or not.

Upon review, this commit was found to be incorrect for the reasons
below, so it must be reverted.  It will be fixed up "correctly" in a
later kernel change.

The original commit causes a memory leak and does not properly fix the
issue it claims to fix.  I will send a follow-on patch to resolve this
properly.

Cc: Kangjie Lu <kjlu@umn.edu>
Cc: Ursula Braun <ubraun@linux.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Link: https://lore.kernel.org/r/20210503115736.2104747-17-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/smc/smc_ism.c | 5 -----
 1 file changed, 5 deletions(-)

diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c
index 9c6e95882553..6558cf7643a7 100644
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -417,11 +417,6 @@ struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
 	init_waitqueue_head(&smcd->lgrs_deleted);
 	smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
 						 WQ_MEM_RECLAIM, name);
-	if (!smcd->event_wq) {
-		kfree(smcd->conn);
-		kfree(smcd);
-		return NULL;
-	}
 	return smcd;
 }
 EXPORT_SYMBOL_GPL(smcd_alloc_dev);
-- 
2.30.2

[PATCH AUTOSEL 5.12 11/63] net/smc: properly handle workqueue allocation failure

[Sasha Levin]

From: Anirudh Rayabharam <mail@anirudhrb.com>

[ Upstream commit bbeb18f27a44ce6adb00d2316968bc59dc640b9b ]

In smcd_alloc_dev(), if alloc_ordered_workqueue() fails, properly catch
it, clean up and return NULL to let the caller know there was a failure.
Move the call to alloc_ordered_workqueue higher in the function in order
to abort earlier without needing to unwind the call to device_initialize().

Cc: Ursula Braun <ubraun@linux.ibm.com>
Cc: David S. Miller <davem@davemloft.net>
Signed-off-by: Anirudh Rayabharam <mail@anirudhrb.com>
Link: https://lore.kernel.org/r/20210503115736.2104747-18-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 net/smc/smc_ism.c | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/net/smc/smc_ism.c b/net/smc/smc_ism.c
index 6558cf7643a7..94b31f2551bc 100644
--- a/net/smc/smc_ism.c
+++ b/net/smc/smc_ism.c
@@ -402,6 +402,14 @@ struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
 		return NULL;
 	}
 
+	smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
+						 WQ_MEM_RECLAIM, name);
+	if (!smcd->event_wq) {
+		kfree(smcd->conn);
+		kfree(smcd);
+		return NULL;
+	}
+
 	smcd->dev.parent = parent;
 	smcd->dev.release = smcd_release;
 	device_initialize(&smcd->dev);
@@ -415,8 +423,6 @@ struct smcd_dev *smcd_alloc_dev(struct device *parent, const char *name,
 	INIT_LIST_HEAD(&smcd->vlan);
 	INIT_LIST_HEAD(&smcd->lgr_list);
 	init_waitqueue_head(&smcd->lgrs_deleted);
-	smcd->event_wq = alloc_ordered_workqueue("ism_evt_wq-%s)",
-						 WQ_MEM_RECLAIM, name);
 	return smcd;
 }
 EXPORT_SYMBOL_GPL(smcd_alloc_dev);
-- 
2.30.2