net: usb: fix possible use-after-free in smsc75xx_bind
authorDongliang Mu <mudongliangabcd@gmail.com>
Wed, 16 Jun 2021 02:48:33 +0000 (10:48 +0800)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 23 Jun 2021 12:42:46 +0000 (14:42 +0200)
commit570a52cf3e01d19f7fd1a251dfc52b0cd86c13cb
tree09461826763d68bd268950556f70e53206fd38bf
parent70c8418469fb22a679fe5015ebe60fe15011ea43
net: usb: fix possible use-after-free in smsc75xx_bind

[ Upstream commit 56b786d86694e079d8aad9b314e015cd4ac02a3d ]

The commit 46a8b29c6306 ("net: usb: fix memory leak in smsc75xx_bind")
fails to clean up the work scheduled in smsc75xx_reset->
smsc75xx_set_multicast, which leads to use-after-free if the work is
scheduled to start after the deallocation. In addition, this patch
also removes a dangling pointer - dev->data[0].

This patch calls cancel_work_sync to cancel the scheduled work and set
the dangling pointer to NULL.

Fixes: 46a8b29c6306 ("net: usb: fix memory leak in smsc75xx_bind")
Signed-off-by: Dongliang Mu <mudongliangabcd@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/net/usb/smsc75xx.c