The Linux kernel before 2.6.25.10 does not properly perform tty operations which allows local users to cause a denial of service (system crash) or possibly gain privileges via vectors involving NULL pointer dereference of function pointers in (1) hamradio/6pack.c (2) hamradio/mkiss.c (3) irda/irtty-sir.c (4) ppp_async.c (5) ppp_synctty.c (6) slip.c (7) wan/x25_asy.c and (8) wireless/strip.c in drivers/net/.