From: Eric Auger eric.auger@redhat.com
commit 4c80ba392bf603d468ea827d902f8e7b2505fbf4 upstream.
In case the new region gets merged into another one, the nr list node is freed. Checking its type while completing the merge algorithm leads to a use-after-free. Use new->type instead.
Fixes: 4dbd258ff63e ("iommu: Revisit iommu_insert_resv_region() implementation") Signed-off-by: Eric Auger eric.auger@redhat.com Reported-by: Qian Cai cai@lca.pw Reviewed-by: Jerry Snitselaar jsnitsel@redhat.com Cc: Stable stable@vger.kernel.org #v5.3+ Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/iommu/iommu.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/iommu/iommu.c +++ b/drivers/iommu/iommu.c @@ -312,8 +312,8 @@ int iommu_insert_resv_region(struct iomm list_for_each_entry_safe(iter, tmp, regions, list) { phys_addr_t top_end, iter_end = iter->start + iter->length - 1;
- /* no merge needed on elements of different types than @nr */ - if (iter->type != nr->type) { + /* no merge needed on elements of different types than @new */ + if (iter->type != new->type) { list_move_tail(&iter->list, &stack); continue; }