From bae88e3798dae246872a03c43ad4cfa6d9317717 Mon Sep 17 00:00:00 2001
From: Pavel Skripkin <paskripkin@gmail.com>
Date: Wed, 4 Aug 2021 18:52:20 +0300
Subject: [PATCH 1/7] net: vxge: fix use-after-free in vxge_device_unregister
Git-commit: 942e560a3d3862dd5dee1411dbdd7097d29b8416
Patch-mainline: v5.14-rc5
References: git-fixes
Smatch says:
drivers/net/ethernet/neterion/vxge/vxge-main.c:3518 vxge_device_unregister() error: Using vdev after free_{netdev,candev}(dev);
drivers/net/ethernet/neterion/vxge/vxge-main.c:3518 vxge_device_unregister() error: Using vdev after free_{netdev,candev}(dev);
drivers/net/ethernet/neterion/vxge/vxge-main.c:3520 vxge_device_unregister() error: Using vdev after free_{netdev,candev}(dev);
drivers/net/ethernet/neterion/vxge/vxge-main.c:3520 vxge_device_unregister() error: Using vdev after free_{netdev,candev}(dev);
Since vdev pointer is netdev private data accessing it after free_netdev()
call can cause use-after-free bug. Fix it by moving free_netdev() call at
the end of the function
Fixes: 6cca200362b4 ("vxge: cleanup probe error paths")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Reviewed-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Denis Kirjanov <denis.kirjanov@suse.com>
---
drivers/net/ethernet/neterion/vxge/vxge-main.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/drivers/net/ethernet/neterion/vxge/vxge-main.c b/drivers/net/ethernet/neterion/vxge/vxge-main.c
index 5dd5f61e1114..683b1ab8fd6e 100644
--- a/drivers/net/ethernet/neterion/vxge/vxge-main.c
+++ b/drivers/net/ethernet/neterion/vxge/vxge-main.c
@@ -3537,13 +3537,13 @@ static void vxge_device_unregister(struct __vxge_hw_device *hldev)
kfree(vdev->vpaths);
- /* we are safe to free it now */
- free_netdev(dev);
-
vxge_debug_init(vdev->level_trace, "%s: ethernet device unregistered",
buf);
vxge_debug_entryexit(vdev->level_trace, "%s: %s:%d Exiting...", buf,
__func__, __LINE__);
+
+ /* we are safe to free it now */
+ free_netdev(dev);
}
/*
--
2.16.4