On Tue, May 09, 2023 at 01:21:22PM -0500, Bjorn Helgaas wrote:
> On Tue, Apr 04, 2023 at 11:11:01AM -0500, Bjorn Helgaas wrote:
> > On Thu, Mar 30, 2023 at 07:24:27PM +0300, Andy Shevchenko wrote:
> > > Provide two new helper macros to iterate over PCI device resources and
> > > convert users.
>
> > Applied 2-7 to pci/resource for v6.4, thanks, I really like this!
>
> This is 09cc90063240 ("PCI: Introduce pci_dev_for_each_resource()")
> upstream now.
>
> Coverity complains about each use,
It needs more clarification here. Use of reduced variant of the macro or all of
them? If the former one, then I can speculate that Coverity (famous for false
positives) simply doesn't understand `for (type var; var ...)` code.
> sample below from
> drivers/pci/vgaarb.c. I didn't investigate at all, so it might be a
> false positive; just FYI.
>
> 1. Condition screen_info.capabilities & (2U /* 1 << 1 */), taking
> true branch.
> 556 if (screen_info.capabilities & VIDEO_CAPABILITY_64BIT_BASE)
> 557 base |= (u64)screen_info.ext_lfb_base << 32;
> 558
> 559 limit = base + size;
> 560
> 561 /* Does firmware framebuffer belong to us? */
> 2. Condition __b < PCI_NUM_RESOURCES, taking true branch.
> 3. Condition (r = &pdev->resource[__b]) , (__b < PCI_NUM_RESOURCES),
> taking true branch.
> 6. Condition __b < PCI_NUM_RESOURCES, taking true branch.
> 7. cond_at_most: Checking __b < PCI_NUM_RESOURCES implies that __b
> may be up to 16 on the true branch.
> 8. Condition (r = &pdev->resource[__b]) , (__b < PCI_NUM_RESOURCES),
> taking true branch.
> 11. incr: Incrementing __b. The value of __b may now be up to 17.
> 12. alias: Assigning: r = &pdev->resource[__b]. r may now point to as
> high as element 17 of pdev->resource (which consists of 17 64-byte elements).
> 13. Condition __b < PCI_NUM_RESOURCES, taking true branch.
> 14. Condition (r = &pdev->resource[__b]) , (__b < PCI_NUM_RESOURCES),
> taking true branch.
> 562 pci_dev_for_each_resource(pdev, r) {
> 4. Condition resource_type(r) != 512, taking true branch.
> 9. Condition resource_type(r) != 512, taking true branch.
>
> CID 1529911 (#1 of 1): Out-of-bounds read (OVERRUN)
> 15. overrun-local: Overrunning array of 1088 bytes at byte offset 1088 by
> dereferencing pointer r. [show details]
> 563 if (resource_type(r) != IORESOURCE_MEM)
> 5. Continuing loop.
> 10. Continuing loop.
> 564 continue;
--
With Best Regards,
Andy Shevchenko
