4.9-stable review patch. If anyone has any objections, please let me know.
------------------ From: Gilad Ben-Yossef <[email protected]> commit a5dfefb1c3f3db81662556393fd9283511e08430 upstream. drbg_kcapi_sym_ctr() was using wait_for_completion_interruptible() to wait for completion of async crypto op but if a signal occurs it may return before DMA ops of HW crypto provider finish, thus corrupting the output buffer. Resolve this by using wait_for_completion() instead. Reported-by: Eric Biggers <[email protected]> Signed-off-by: Gilad Ben-Yossef <[email protected]> Signed-off-by: Herbert Xu <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- crypto/drbg.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/crypto/drbg.c +++ b/crypto/drbg.c @@ -1768,9 +1768,8 @@ static int drbg_kcapi_sym_ctr(struct drb break; case -EINPROGRESS: case -EBUSY: - ret = wait_for_completion_interruptible( - &drbg->ctr_completion); - if (!ret && !drbg->ctr_async_err) { + wait_for_completion(&drbg->ctr_completion); + if (!drbg->ctr_async_err) { reinit_completion(&drbg->ctr_completion); break; }
