Re: [PATCH 3/7] syscalls/fanotify20: Validate incoming FID in FAN_FS_ERROR

[Matthew Bobrowski <repnop@google.com>]

On Wed, Aug 04, 2021 at 08:39:55AM +0300, Amir Goldstein wrote:
> On Wed, Aug 4, 2021 at 7:54 AM Gabriel Krisman Bertazi
> <krisman@collabora.com> wrote:
> >
> > Amir Goldstein <amir73il@gmail.com> writes:
> >
> > > On Tue, Aug 3, 2021 at 12:47 AM Gabriel Krisman Bertazi
> > > <krisman@collabora.com> wrote:
> > >>
> > >> Verify the FID provided in the event.  If the testcase has a null inode,
> > >> this is assumed to be a superblock error (i.e. null FH).
> > >>
> > >> Signed-off-by: Gabriel Krisman Bertazi <krisman@collabora.com>
> > >> ---
> > >>  .../kernel/syscalls/fanotify/fanotify20.c     | 51 +++++++++++++++++++
> > >>  1 file changed, 51 insertions(+)
> > >>
> > >> diff --git a/testcases/kernel/syscalls/fanotify/fanotify20.c b/testcases/kernel/syscalls/fanotify/fanotify20.c
> > >> index fd5cfb8744f1..d8d788ae685f 100644
> > >> --- a/testcases/kernel/syscalls/fanotify/fanotify20.c
> > >> +++ b/testcases/kernel/syscalls/fanotify/fanotify20.c
> > >> @@ -40,6 +40,14 @@
> > >>
> > >>  #define FAN_EVENT_INFO_TYPE_ERROR      4
> > >>
> > >> +#ifndef FILEID_INVALID
> > >> +#define        FILEID_INVALID          0xff
> > >> +#endif
> > >> +
> > >> +#ifndef FILEID_INO32_GEN
> > >> +#define FILEID_INO32_GEN       1
> > >> +#endif
> > >> +
> > >>  struct fanotify_event_info_error {
> > >>         struct fanotify_event_info_header hdr;
> > >>         __s32 error;
> > >> @@ -57,6 +65,9 @@ static const struct test_case {
> > >>         char *name;
> > >>         int error;
> > >>         unsigned int error_count;
> > >> +
> > >> +       /* inode can be null for superblock errors */
> > >> +       unsigned int *inode;
> > >
> > > Any reason not to use fanotify_fid_t * like fanotify16.c?
> >
> > No reason other than I didn't notice they existed. Sorry. I will get
> > this fixed.
> 
> No problem. That's what review is for ;-)
> 
> BTW, unless anyone is specifically interested I don't think there
> is a reason to re post the test patches before the submission request.
> Certainly not for the small fixes that I requested.
> 
> I do request that you post a link to a branch with the fixed test
> so that we can experiment with the kernel patches.
> 
> I've also CC'ed Matthew who may want to help with review of the test
> and man page that you posted in the cover letter [1].

I'll get around to going through both the LTP and man-page series by the
end of this week. Feel free to also loop me in directly on any subsequent
iterations of the like.

/M