On Sat, Oct 30, 2010 at 06:37:16PM +0200, Jesper Juhl wrote: > I noticed that the return value of the > vmalloc() call in arch/mips/kernel/vpe.c::vpe_open() is not checked, so we > potentially store a null pointer in v->pbuffer. As far as I can tell this > will be a problem. However, I don't know the mips code at all, so there > may be something, somewhere where I did not look, that handles this in a > safe manner but I couldn't find it. > > To me it looks like we should do what the patch below implements and check > for a null return and then return -ENOMEM in that case. Comments? All users check if the buffer was successfully allocated so the code is safe wrt. to that. Doesn't mean that it's not a pukeogenic piece of code. Look at the use of v->pbuffer in vpe_release for example. First use it the vmalloc'ed memory then carefully check the pointer for being non-NULL before calling vfree. If the pointer could actually be non-NULL that's too late and vfree does that check itself anyway. And more such gems, general uglyness and freedom of concept. It used to be even worse. Ralf
