[lkml]   [2004]   [Oct]   [6]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRE: UDP recvmsg blocks after select(), 2.6 bug?
> Hua Zhong wrote:
> > How hard is it to treat the next read to the fd as
> NON_BLOCKING, even if
> > it's not set?
> Userspace likely would not properly handle EAGAIN on a
> nonblocking socket.

But it's better than blocking the call, isn't it?

If the caller is using NON_BLOCKING already, no change in behavior,
otherwise it returns an error which the app may or may not handle, instead
of blocking it (which is usually fatal). Plus it hopefully gives Posix

I can see there could be remote DoS attacks by just sending malformed UDP

> As far as I can tell, either you block, or you have to scan
> the checksum before
> select() returns.
> Would it be so bad to do the checksum before marking the
> socket readable?
> Chances are we're going to receive the message "soon"
> anyways, so there is at
> least a chance it will stay hot in the cache, no?
> Chris

To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to
More majordomo info at
Please read the FAQ at

 \ /
  Last update: 2005-03-22 14:06    [from the cache]
©2003-2014 Jasper Spaans. hosted at Digital Ocean