On Fri, 2019-12-13 at 21:53 +0100, Arnd Bergmann wrote:
Most kernel interfaces that take a timespec require normalized representation with tv_nsec between 0 and NSEC_PER_SEC.
Passing values larger than 0x100000000ull further behaves differently on 32-bit and 64-bit kernels, and can cause the latter to spend a long time counting seconds in timespec64_sub()/set_normalized_timespec64().
Reject those large values at the user interface to enforce sane and portable behavior.
Signed-off-by: Arnd Bergmann arnd@arndb.de
drivers/gpu/drm/etnaviv/etnaviv_drv.c | 9 +++++++++ 1 file changed, 9 insertions(+)
diff --git a/drivers/gpu/drm/etnaviv/etnaviv_drv.c b/drivers/gpu/drm/etnaviv/etnaviv_drv.c index 1f9c01be40d7..95d72dc00280 100644 --- a/drivers/gpu/drm/etnaviv/etnaviv_drv.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_drv.c @@ -297,6 +297,9 @@ static int etnaviv_ioctl_gem_cpu_prep(struct drm_device *dev, void *data, if (args->op & ~(ETNA_PREP_READ | ETNA_PREP_WRITE | ETNA_PREP_NOSYNC)) return -EINVAL;
- if (args->timeout.tv_nsec > NSEC_PER_SEC)
[...]
There's an off-by-one error between the subject line and the actual changes. The subject line seems to have the correct comparison.
Ben.