On Mon, Jun 03, 2013 at 09:07:05PM +0200, Oleg Nesterov wrote: > 1. proc_task_readdir() truncates f_pos to long, this can lead > to wrong result on 32bit. > > 2. first_tid() truncates f_pos to int, this is wrong even on > 64bit. > > We could check that f_pos < PID_MAX or even INT_MAX in > proc_task_readdir(), but this patch simply checks the > potential overflow in first_tid(), this check is nop on > 64bit. We do not care if it was negative and the new > unsigned value is huge, all we need to ensure is that we > never wrongly return !NULL. > > 3. Remove the 2nd "nr != 0" check before get_nr_threads(), > nr_threads == 0 is not distinguishable from !pid_task() > above.
Oleg, please take a look at the series in vfs.git#experimental; at the very least, we don't want to access file->f_pos in any foo_readdir() - it's too messy and race-prone. It's pretty much independent from the issues you are dealing with, but let's avoid creating pointless conflicts... -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/