IOMMU Archive on lore.kernel.org
 help / color / Atom feed
* [PATCH v4] iommu: fix KASAN use-after-free in iommu_insert_resv_region
@ 2019-11-26 17:54 Eric Auger
  0 siblings, 0 replies; only message in thread
From: Eric Auger @ 2019-11-26 17:54 UTC (permalink / raw)
  To: eric.auger.pro, eric.auger, joro, hch, cai, iommu, linux-kernel

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+

---

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

_______________________________________________
iommu mailing list
iommu@lists.linux-foundation.org
https://lists.linuxfoundation.org/mailman/listinfo/iommu

^ permalink raw reply	[flat|nested] only message in thread

only message in thread, back to index

Thread overview: (only message) (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-11-26 17:54 [PATCH v4] iommu: fix KASAN use-after-free in iommu_insert_resv_region Eric Auger

IOMMU Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-iommu/0 linux-iommu/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-iommu linux-iommu/ https://lore.kernel.org/linux-iommu \
		iommu@lists.linux-foundation.org
	public-inbox-index linux-iommu

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.linux-foundation.lists.iommu


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git