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 <[email protected]>
Reported-by: Qian Cai <[email protected]>
Reviewed-by: Jerry Snitselaar <[email protected]>
Cc: Stable <[email protected]> #v5.3+
---
v3 -> v4:
- s/nr/new in the comment
- Added Jerry's R-b
v2 -> v3:
- directly use new->type
v1 -> v2:
- remove spurious new line
---
drivers/iommu/iommu.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c
index d658c7c6a2ab..dea1069334a4 100644
--- a/drivers/iommu/iommu.c
+++ b/drivers/iommu/iommu.c
@@ -312,8 +312,8 @@ int iommu_insert_resv_region(struct iommu_resv_region *new,
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;
}
--
2.20.1