Commit a92ce570 authored by Dan Carpenter's avatar Dan Carpenter Committed by Corey Minyard
Browse files

ipmi: fix use after free in _ipmi_destroy_user() 



The intf_free() function frees the "intf" pointer so we cannot
dereference it again on the next line.

Fixes: cbb79863 ("ipmi: Don't allow device module unload when in use")
Signed-off-by: default avatarDan Carpenter <error27@gmail.com>
Message-Id: <Y3M8xa1drZv4CToE@kili>
Cc: <stable@vger.kernel.org> # 5.5+
Signed-off-by: default avatarCorey Minyard <cminyard@mvista.com>
parent 0eb1762f

drivers/char/ipmi/ipmi_msghandler.c

+3 −1
Original line number Diff line number Diff line
@@ -1330,6 +1330,7 @@ static void _ipmi_destroy_user(struct ipmi_user *user) 
	unsigned long    flags;

	struct cmd_rcvr  *rcvr;

	struct cmd_rcvr  *rcvrs = NULL;

	struct module    *owner;



	if (!acquire_ipmi_user(user, &i)) {

		/*
@@ -1392,8 +1393,9 @@ static void _ipmi_destroy_user(struct ipmi_user *user) 
		kfree(rcvr);

	}



	owner = intf->owner;

	kref_put(&intf->refcount, intf_free);

	module_put(intf->owner);

	module_put(owner);

}



int ipmi_destroy_user(struct ipmi_user *user)