sch_dsmark bug

[Hugo Santos <hugo@innerghost.net>]

Hi there,

I tried to contact the person whose name is in the source file but with
no success. While developing some code that handles with kernel's TC
objects direcly (by netlink) i found a small problem with dsmark (maybe
other scheds have it too, but i haven't checked). This is in linux 2.6.4
(there is no change in this context in 2.6.5); in dsmark_init, if opt is
NULL, the module will crash and TC will get stuck. the module will have a
ref count of 1 so i can't unload it, and i can't change any other TC
stuff since the netlink socket gets stuck when dsmark crashes. So, a simple

if (!opt) return -EINVAL;

would prevent such problems.

If you prefer i may send a patch, but since it's only a one line patch i didn't
send one.

Best regards,
Hugo Santos