From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Zhang Bo , Will Deacon Subject: [PATCH 4.4 077/117] iommu/io-pgtable-arm: Ensure we free the final level on teardown Date: Sun, 14 Feb 2016 14:21:54 -0800 Message-Id: <20160214222143.735434195@linuxfoundation.org> In-Reply-To: <20160214222141.393531627@linuxfoundation.org> References: <20160214222141.393531627@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Will Deacon commit 12c2ab09571e8aae3a87da2a4a452632a5fac1e5 upstream. When tearing down page tables, we return early for the final level since we know that we won't have any table pointers to follow. Unfortunately, this also means that we forget to free the final level, so we end up leaking memory. Fix the issue by always freeing the current level, but just don't bother to iterate over the ptes if we're at the final level. Reported-by: Zhang Bo Signed-off-by: Will Deacon Signed-off-by: Greg Kroah-Hartman --- drivers/iommu/io-pgtable-arm.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) --- a/drivers/iommu/io-pgtable-arm.c +++ b/drivers/iommu/io-pgtable-arm.c @@ -405,17 +405,18 @@ static void __arm_lpae_free_pgtable(stru arm_lpae_iopte *start, *end; unsigned long table_size; - /* Only leaf entries at the last level */ - if (lvl == ARM_LPAE_MAX_LEVELS - 1) - return; - if (lvl == ARM_LPAE_START_LVL(data)) table_size = data->pgd_size; else table_size = 1UL << data->pg_shift; start = ptep; - end = (void *)ptep + table_size; + + /* Only leaf entries at the last level */ + if (lvl == ARM_LPAE_MAX_LEVELS - 1) + end = ptep; + else + end = (void *)ptep + table_size; while (ptep != end) { arm_lpae_iopte pte = *ptep++;