CVE request: kernel: pipe_fcntl local DoS

[Eugene Teo <eugene () redhat com>]

"Export 'get_pipe_info()' to other users

And in particular, use it in 'pipe_fcntl()'.

The other pipe functions do not need to use the 'careful' version, since 
they are only ever called for things that are already known to be pipes.

The normal read/write/ioctl functions are called through the file 
operations structures, so if a file isn't a pipe, they'd never get 
called.  But pipe_fcntl() is special, and called directly from the 
generic fcntl code, and needs to use the same careful function that the 
splice code is using."

In other words, this is a pipe_fcntl local DoS.

http://git.kernel.org/linus/71993e62a47dabddf10302807d6aa260455503f4
http://git.kernel.org/linus/c66fb347946ebdd5b10908866ecc9fa05ee2cf3d

Introduced in v2.6.35-rc1

Thanks, Eugene