[PATCH 2/3] arch/s390/kvm: copy userspace-array safely

[Philipp Stanner]

guestdbg.c utilizes memdup_user() to copy a userspace array. This,
currently, does not check for an overflow.

Use the new wrapper memdup_array_user() to copy the array more safely.

Suggested-by: Dave Airlie <airlied@xxxxxxxxxx>
Signed-off-by: Philipp Stanner <pstanner@xxxxxxxxxx>
---
 arch/s390/kvm/guestdbg.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/s390/kvm/guestdbg.c b/arch/s390/kvm/guestdbg.c
index 3765c4223bf9..80879fc73c90 100644
--- a/arch/s390/kvm/guestdbg.c
+++ b/arch/s390/kvm/guestdbg.c
@@ -213,8 +213,8 @@ int kvm_s390_import_bp_data(struct kvm_vcpu *vcpu,
 	else if (dbg->arch.nr_hw_bp > MAX_BP_COUNT)
 		return -EINVAL;
 
-	bp_data = memdup_user(dbg->arch.hw_bp,
-			      sizeof(*bp_data) * dbg->arch.nr_hw_bp);
+	bp_data = memdup_array_user(dbg->arch.hw_bp, dbg->arch.nr_hw_bp,
+				    sizeof(*bp_data));
 	if (IS_ERR(bp_data))
 		return PTR_ERR(bp_data);
 
-- 
2.41.0