lkml.org 
[lkml]   [2015]   [Dec]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
From
Date
SubjectRe: [PATCH] devpts: Sensible /dev/ptmx & force newinstance
On Fri, Dec 11, 2015 at 1:11 PM, Eric W. Biederman
<ebiederm@xmission.com> wrote:
> Al Viro <viro@ZenIV.linux.org.uk> writes:
>
>> On Fri, Dec 11, 2015 at 01:40:40PM -0600, Eric W. Biederman wrote:
>>
>>> + inode = path.dentry->d_inode;
>>> + filp->f_path = path;
>>> + filp->f_inode = inode;
>>> + filp->f_mapping = inode->i_mapping;
>>> + path_put(&old);
>>
>> Don't. You are creating a fairly subtle constraint on what the code in
>> fs/open.c and fs/namei.c can do, for no good reason. You can bloody
>> well maintain the information you need without that.
>
> There is a good reason. We can not write a race free version of ptsname
> without it.

As long as this is for new userspace code, would it make sense to just
add a new ioctl to ask "does this ptmx fd match this /dev/pts fd?"

--Andy


\
 
 \ /
  Last update: 2015-12-11 23:01    [W:0.622 / U:0.044 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site