Messages in this thread | | | Date | Mon, 25 Mar 2019 16:09:54 +0200 | From | Jarkko Sakkinen <> | Subject | Re: [PATCH RESEND v3] tpm: fix an invalid condition in tpm_common_poll |
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On Fri, Mar 22, 2019 at 05:59:17PM +0200, Jarkko Sakkinen wrote: > On Fri, Mar 22, 2019 at 07:38:58AM -0700, Tadeusz Struk wrote: > > The poll condition should only check response_length, > > because reads should only be issued if there is data to read. > > The response_read flag only prevents double writes. > > The problem was that the write set the response_read to false, > > enqued a tpm job, and returned. Then application called poll > > which checked the response_read flag and returned EPOLLIN. > > Then the application called read, but got nothing. > > After all that the async_work kicked in. > > Added also mutex_lock around the poll check to prevent > > other possible race conditions. > > > > Cc: stable@vger.kernel.org > > Fixes: 9488585b21bef0df12 ("tpm: add support for partial reads") > > Reported-by: Mantas Mikulėnas <grawity@gmail.com> > > Tested-by: Mantas Mikulėnas <grawity@gmail.com> > > Signed-off-by: Tadeusz Struk <tadeusz.struk@intel.com> > > Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
It is still missing the comment I asked to add. Otherwise, it is good.
/Jarkko
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