lkml.org 
[lkml]   [2019]   [Mar]   [25]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH RESEND v3] tpm: fix an invalid condition in tpm_common_poll
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

\
 
 \ /
  Last update: 2019-03-25 15:10    [W:0.064 / U:0.184 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site