On Thu, Mar 21, 2019 at 04:02:12PM -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.
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
drivers/char/tpm/tpm-dev-common.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-)
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This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read: https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html for how to do this properly.
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