Re: [RFC][PATCH] procfs: Add /proc/<pid>/mapped_files

[Calvin Owens]

On Wednesday 01/14 at 18:33 +0300, Cyrill Gorcunov wrote:
> On Wed, Jan 14, 2015 at 05:25:01PM +0200, Kirill A. Shutemov wrote:
> ...
> > > 
> > > This gives lsof and suchlike a way to determine the pathnames of files
> > > mapped into a process without incurring the O(N^2) behavior of the
> > > maps file.
> > 
> > We already have /proc/PID/map_files/ directory which lists all mapped
> > files. Should we consider relaxing permission checking there and move it
> > outside CONFIG_CHECKPOINT_RESTORE instead?
> > 
> > Restriction to CAP_SYSADMIN for follow_link is undertansble, but why do we
> > restrict readdir and readlink?
> 
> We didn't think this functionality might be needed someone but us (criu camp),
> so that the rule of thumb was CONFIG_CHECKPOINT_RESTORE + CAP_SYSADMIN, until
> otherwise strictly needed. So I think now we can relax security rules a bit
> and allow to readdir and such for owners.

Ah, I feel silly for missing that. I'll send a patch to move map_files
out from behind CONFIG_CHECKPOINT_RESTORE and change the permissions.

Thanks,
Calvin
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/