[ Upstream commit 3ee9eca760e7d0b68c55813243de66bbb499dc3b ] There is a couple of places where on domain_init() failure domain_exit() is called. While currently domain_init() can fail only if alloc_pgtable_page() has failed.
Make domain_exit() check if domain->pgd present, before calling domain_unmap(), as it theoretically should crash on clearing pte entries in dma_pte_clear_level(). Cc: David Woodhouse <[email protected]> Cc: Joerg Roedel <[email protected]> Cc: Lu Baolu <[email protected]> Cc: [email protected] Signed-off-by: Dmitry Safonov <[email protected]> Reviewed-by: Lu Baolu <[email protected]> Signed-off-by: Joerg Roedel <[email protected]> Signed-off-by: Sasha Levin <[email protected]> --- drivers/iommu/intel-iommu.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 2101601adf57d..1ad24367373f4 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -1900,7 +1900,6 @@ static int domain_init(struct dmar_domain *domain, struct intel_iommu *iommu, static void domain_exit(struct dmar_domain *domain) { - struct page *freelist; /* Remove associated devices and clear attached or cached domains */ rcu_read_lock(); @@ -1910,9 +1909,12 @@ static void domain_exit(struct dmar_domain *domain) /* destroy iovas */ put_iova_domain(&domain->iovad); - freelist = domain_unmap(domain, 0, DOMAIN_MAX_PFN(domain->gaw)); + if (domain->pgd) { + struct page *freelist; - dma_free_pagelist(freelist); + freelist = domain_unmap(domain, 0, DOMAIN_MAX_PFN(domain->gaw)); + dma_free_pagelist(freelist); + } free_domain_mem(domain); } -- 2.20.1
