[issue2019] panic: file desc: malloc limit exceeded

[Matthew Dillon]

:Venkatesh Srinivas <vsrinivas at dragonflybsd.org> added the comment:
:
:Commit 2994659f1e6c1ef260241491bceca91c9d2553b3 is a partial fix to the problem;
:it does not handle overflows in the spinlock loop path in fdcopy and it is still
:possible to make the system unusable with the sample program posted below.
:
:Perhaps we should also raise the malloc zone limit to maxproc * MAX_FDS_PER_PROC?

   No, won't work, the maximum will baloon well past any reasonable limit
   when you try to do that.

   We have a kern.maxfilesperuser that's supposed to handle that sort of
   attack, is it not working?  It might not be applicable to root though.

					-Matt
					Matthew Dillon 
					<dillon at backplane.com>