Coverity: iommufd_vfio_iommu_get_info(): Code maintainability issues

coverity-bot
2022-11-02T19:55:27Z

Hello!

This is an experimental semi-automated report about issues detected by
Coverity from a scan of next-20221102 as part of the linux-next scan project:
https://scan.coverity.com/projects/linux-next-weekly-scan

You're getting this email because you were associated with the identified
lines of code (noted below) that were touched by commits:

Mon Oct 31 13:37:58 2022 -0300
32c328dc9b73 ("iommufd: vfio container FD ioctl compatibility")

Coverity reported the following:

*** CID 1527093: Code maintainability issues (UNUSED_VALUE)
/drivers/iommu/iommufd/vfio_compat.c: 411 in iommufd_vfio_iommu_get_info()
405 */
406 if (info.argsz >= total_cap_size)
407 info.cap_offset = sizeof(info);
408 info.argsz = total_cap_size;
409 info.flags |= VFIO_IOMMU_INFO_CAPS;
410 if (copy_to_user(arg, &info, minsz))
vvv CID 1527093: Code maintainability issues (UNUSED_VALUE)
vvv Assigning value "-14" to "rc" here, but that stored value is overwritten before it can be used.
411 rc = -EFAULT;
412 rc = 0;
413
414 out_put:
415 up_read(&ioas->iopt.iova_rwsem);
416 iommufd_put_object(&ioas->obj);

If this is a false positive, please let us know so we can mark it as
such, or teach the Coverity rules to be smarter. If not, please make
sure fixes get into linux-next. :) For patches fixing this, please
include these lines (but double-check the "Fixes" first):

Reported-by: coverity-bot <keescook+coverity-bot@chromium.org>
Addresses-Coverity-ID: 1527093 ("Code maintainability issues")
Fixes: 32c328dc9b73 ("iommufd: vfio container FD ioctl compatibility")

This looks more like a "goto" is missing after the -EFAULT assignment?

Thanks for your attention!

--
Coverity-bot