Alex Williamson 5321908ef7 vfio/type1: Unpin zero pages ... commit 873aefb376 upstream. There's currently a reference count leak on the zero page. We increment the reference via pin_user_pages_remote(), but the page is later handled as an invalid/reserved page, therefore it's not accounted against the user and not unpinned by our put_pfn(). Introducing special zero page handling in put_pfn() would resolve the leak, but without accounting of the zero page, a single user could still create enough mappings to generate a reference count overflow. The zero page is always resident, so for our purposes there's no reason to keep it pinned. Therefore, add a loop to walk pages returned from pin_user_pages_remote() and unpin any zero pages. Cc: stable@vger.kernel.org Reported-by: Luboslav Pivarc <lpivarc@redhat.com> Reviewed-by: David Hildenbrand <david@redhat.com> Link: https://lore.kernel.org/r/166182871735.3518559.8884121293045337358.stgit@omen Signed-off-by: Alex Williamson <alex.williamson@redhat.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2022-09-15 11:30:02 +02:00
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fsl-mc	vfio: Use kconfig if XX/endif blocks instead of repeating 'depends on'	2021-08-26 10:36:51 -06:00
mdev	VFIO update for v5.15-rc1	2021-09-02 13:41:33 -07:00
pci	vfio/pci: Fix vf_token mechanism when device-specific VF drivers are used	2022-04-20 09:34:13 +02:00
platform	Merge branches 'v5.15/vfio/spdx-license-cleanups', 'v5.15/vfio/dma-valid-waited-v3', 'v5.15/vfio/vfio-pci-core-v5' and 'v5.15/vfio/vfio-ap' into v5.15/vfio/next	2021-08-26 11:08:50 -06:00
Kconfig	vfio: Use kconfig if XX/endif blocks instead of repeating 'depends on'	2021-08-26 10:36:51 -06:00
Makefile	vfio/fsl-mc: Add VFIO framework skeleton for fsl-mc devices	2020-10-07 14:17:33 -06:00
vfio.c	vfio: Clear the caps->buf to NULL after free	2022-08-25 11:40:41 +02:00
vfio_iommu_spapr_tce.c	vfio/spapr_tce: convert get_user_pages() --> pin_user_pages()	2020-07-27 13:43:38 -06:00
vfio_iommu_type1.c	vfio/type1: Unpin zero pages	2022-09-15 11:30:02 +02:00
vfio_spapr_eeh.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500	2019-06-19 17:09:55 +02:00
virqfd.c	vfio/virqfd: Drain events from eventfd in virqfd_wakeup()	2020-11-15 09:49:10 -05:00