Hi Matthew,
On Wed, 27 Feb 2019 at 08:39, Matthew Bobrowski
<mbobrowski@xxxxxxxxxxxxxx> wrote:
>
> Hi Michael,
>
> On Tue, Feb 26, 2019 at 04:43:01PM +0100, Michael Kerrisk (man-pages) wrote:
> > Hello Matthew,
> >
> > On 1/12/19 2:56 AM, Matthew Bobrowski wrote:
> > > New event masks have been added to the fanotify API. Documentation to
> > > support the use and behaviour of these new masks has been added
> > > accordingly.
> > >
> > > Signed-off-by: Matthew Bobrowski <mbobrowski@xxxxxxxxxxxxxx>
> > > Reviewed-by: Amir Goldstein <amir73il@xxxxxxxxx>
> >
> > Thanks for the patch. I've applied, but I have a question below.
>
> Sure, response to your question is inline below.
>
> > > ---
> > > man2/fanotify_mark.2 | 60 ++++++++++++++++++++++++++++++++++++++++++++
> > > man7/fanotify.7 | 18 +++++++++++++
> > > 2 files changed, 78 insertions(+)
> > >
> > > diff --git a/man2/fanotify_mark.2 b/man2/fanotify_mark.2
> > > index a9a482fe7..613c86cc4 100644
> > > --- a/man2/fanotify_mark.2
> > > +++ b/man2/fanotify_mark.2
> > > @@ -149,6 +149,12 @@ Create an event when a read-only file or directory is closed.
> > > .B FAN_OPEN
> > > Create an event when a file or directory is opened.
> > > .TP
> > > +.B FAN_OPEN_EXEC
> > > +Create an event when a file is opened with the intent to be executed.
> > > +See
> > > +.B NOTES
> > > +for additional details.
> > > +.TP
> > > .B FAN_Q_OVERFLOW
> > > Create an event when an overflow of the event queue occurs.
> > > The size of the event queue is limited to 16384 entries if
> > > @@ -164,6 +170,18 @@ or
> > > .B FAN_CLASS_CONTENT
> > > is required.
> > > .TP
> > > +.B FAN_OPEN_EXEC_PERM
> > > +Create an event when a permission to open a file for execution is
> > > +requested.
> > > +An fanotify file descriptor created with
> > > +.B FAN_CLASS_PRE_CONTENT
> > > +or
> > > +.B FAN_CLASS_CONTENT
> > > +is required.
> > > +See
> > > +.B NOTES
> > > +for additional details.
> > > +.TP
> > > .B FAN_ACCESS_PERM
> > > Create an event when a permission to read a file or directory is requested.
> > > An fanotify file descriptor created with
> > > @@ -309,6 +327,48 @@ was introduced in version 2.6.36 of the Linux kernel and enabled in version
> > > 2.6.37.
> > > .SH CONFORMING TO
> > > This system call is Linux-specific.
> > > +.SH NOTES
> > > +When using either
> > > +.B FAN_OPEN_EXEC
> > > +or
> > > +.B FAN_OPEN_EXEC_PERM
> > > +within the
> > > +.IR mask ,
> > > +events of these types will only be returned when the direct execution of a
> > > +program occurs.
> > > +More specifically, this means that events of these types shall be generated
> > > +for files that are opened using system calls
> > > +.BR execve(2) ,
> > > +.BR execveat(2) ,
> > > +or
> > > +.BR uselib(2) .
> > > +Events of these types will not be raised in the situation where an
> > > +interpreter reads data as input and subsequently results in arbitrary
> > > +computation.
> >
> > This last sentence is not so clear to me. Are you here talking about
> > the situation where (say) awk(1) reads a script file and interprets
> > its contents?
>
> That's correct. Another very similar situation would be where Python is passed
> a file for interpretation.
Thanks. I changed that piece to:
Events of these types will not be raised in the situation where
an interpreter is passed (or reads) a script file for interpre‐
tation.
Cheers,
Michael
--
Michael Kerrisk
Linux man-pages maintainer; http://www.kernel.org/doc/man-pages/
Linux/UNIX System Programming Training: http://man7.org/training/
