Restoring a corrupted collection entry (like an out of range ID) is
being ignored and treated as success. More specifically, a
vgic_its_restore_cte failure is treated as success by
vgic_its_restore_collection_table. vgic_its_restore_cte uses positive
and negative numbers to return error, and +1 to return success. The
caller then uses "ret > 0" to check for success.
Fix this by having vgic_its_restore_cte only return negative numbers on
error. Do this by changing alloc_collection return codes to only return
negative numbers on error.
Signed-off-by: Ricardo Koller <ricarkol@xxxxxxxxxx>
---
arch/arm64/kvm/vgic/vgic-its.c | 27 +++++++++++++++++++++++----
1 file changed, 23 insertions(+), 4 deletions(-)
diff --git a/arch/arm64/kvm/vgic/vgic-its.c b/arch/arm64/kvm/vgic/vgic-its.c
index 8a7db839e3bf..f34e09cc86dc 100644
--- a/arch/arm64/kvm/vgic/vgic-its.c
+++ b/arch/arm64/kvm/vgic/vgic-its.c
@@ -999,15 +999,16 @@ static bool vgic_its_check_event_id(struct vgic_its *its, struct its_device *dev
return __is_visible_gfn_locked(its, gpa);
}
+/*
+ * Add a new collection into the ITS collection table.
+ * Returns 0 on success, and a negative error value for generic errors.
+ */
static int vgic_its_alloc_collection(struct vgic_its *its,
struct its_collection **colp,
u32 coll_id)
{
struct its_collection *collection;
- if (!vgic_its_check_id(its, its->baser_coll_table, coll_id, NULL))
- return E_ITS_MAPC_COLLECTION_OOR;
-
collection = kzalloc(sizeof(*collection), GFP_KERNEL_ACCOUNT);
if (!collection)
return -ENOMEM;
@@ -1101,7 +1102,12 @@ static int vgic_its_cmd_handle_mapi(struct kvm *kvm, struct vgic_its *its,
collection = find_collection(its, coll_id);
if (!collection) {
- int ret = vgic_its_alloc_collection(its, &collection, coll_id);
+ int ret;
+
+ if (!vgic_its_check_id(its, its->baser_coll_table, coll_id, NULL))
+ return E_ITS_MAPC_COLLECTION_OOR;
+
+ ret = vgic_its_alloc_collection(its, &collection, coll_id);
if (ret)
return ret;
new_coll = collection;
@@ -1256,6 +1262,10 @@ static int vgic_its_cmd_handle_mapc(struct kvm *kvm, struct vgic_its *its,
if (!collection) {
int ret;
+ if (!vgic_its_check_id(its, its->baser_coll_table,
+ coll_id, NULL))
+ return E_ITS_MAPC_COLLECTION_OOR;
+
ret = vgic_its_alloc_collection(its, &collection,
coll_id);
if (ret)
@@ -2491,6 +2501,11 @@ static int vgic_its_save_cte(struct vgic_its *its,
return kvm_write_guest_lock(its->dev->kvm, gpa, &val, esz);
}
+/*
+ * Restore a collection entry into the ITS collection table.
+ * Return +1 on success, 0 if the entry was invalid (which should be
+ * interpreted as end-of-table), and a negative error value for generic errors.
+ */
static int vgic_its_restore_cte(struct vgic_its *its, gpa_t gpa, int esz)
{
struct its_collection *collection;
@@ -2517,6 +2532,10 @@ static int vgic_its_restore_cte(struct vgic_its *its, gpa_t gpa, int esz)
collection = find_collection(its, coll_id);
if (collection)
return -EEXIST;
+
+ if (!vgic_its_check_id(its, its->baser_coll_table, coll_id, NULL))
+ return -EINVAL;
+
ret = vgic_its_alloc_collection(its, &collection, coll_id);
if (ret)
return ret;
--
2.36.0.512.ge40c2bad7a-goog
