6.11-stable review patch. If anyone has any objections, please let me know.
------------------
From: Jason Gunthorpe jgg@nvidia.com
[ Upstream commit 322d889ae7d39f8538a6deac35869aa3be1855bd ]
It is a serious bug if the domain is still mapped to any DTEs when it is freed as we immediately start freeing page table memory, so any remaining HW touch will UAF.
If it is not mapped then dev_list is empty and amd_iommu_domain_update() does nothing.
Remove it and add a WARN_ON() to catch this class of bug.
Reviewed-by: Vasant Hegde vasant.hegde@amd.com Signed-off-by: Jason Gunthorpe jgg@nvidia.com Link: https://lore.kernel.org/r/4-v2-831cdc4d00f3+1a315-amd_iopgtbl_jgg@nvidia.com Signed-off-by: Joerg Roedel jroedel@suse.de Stable-dep-of: 016991606aa0 ("iommu/amd/pgtbl_v2: Take protection domain lock before invalidating TLB") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/iommu/amd/io_pgtable.c | 3 --- drivers/iommu/amd/iommu.c | 2 ++ 2 files changed, 2 insertions(+), 3 deletions(-)
diff --git a/drivers/iommu/amd/io_pgtable.c b/drivers/iommu/amd/io_pgtable.c index 05aed3cb46f1b..b3991ad1ae8ea 100644 --- a/drivers/iommu/amd/io_pgtable.c +++ b/drivers/iommu/amd/io_pgtable.c @@ -578,9 +578,6 @@ static void v1_free_pgtable(struct io_pgtable *iop)
/* Update data structure */ amd_iommu_domain_clr_pt_root(dom); - - /* Make changes visible to IOMMUs */ - amd_iommu_domain_update(dom); }
static struct io_pgtable *v1_alloc_pgtable(struct io_pgtable_cfg *cfg, void *cookie) diff --git a/drivers/iommu/amd/iommu.c b/drivers/iommu/amd/iommu.c index 1a61f14459e4f..881f6c589257c 100644 --- a/drivers/iommu/amd/iommu.c +++ b/drivers/iommu/amd/iommu.c @@ -2262,6 +2262,8 @@ void protection_domain_free(struct protection_domain *domain) if (!domain) return;
+ WARN_ON(!list_empty(&domain->dev_list)); + if (domain->iop.pgtbl_cfg.tlb) free_io_pgtable_ops(&domain->iop.iop.ops);