FAILED: patch "[PATCH] iommu/arm-smmu-v3: Don't free page table ops twice" failed to apply to 4.4-stable tree

The patch below does not apply to the 4.4-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From: Jean-Philippe Brucker <[email protected]>
Date: Thu, 14 Dec 2017 11:03:01 +0000
Subject: [PATCH] iommu/arm-smmu-v3: Don't free page table ops twice

Kasan reports a double free when finalise_stage_fn fails: the io_pgtable ops are freed by arm_smmu_domain_finalise and then again by arm_smmu_domain_free. Prevent this by leaving pgtbl_ops empty on failure.

index f122071688fd..db4281d0e269 100644
@@ -1698,13 +1698,15 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain)
 	domain->pgsize_bitmap = pgtbl_cfg.pgsize_bitmap;
 	domain->geometry.aperture_end = (1UL << ias) - 1;
 	domain->geometry.force_aperture = true;
-	smmu_domain->pgtbl_ops = pgtbl_ops;
 
 	ret = finalise_stage_fn(smmu_domain, &pgtbl_cfg);
-	if (ret < 0)
+	if (ret < 0) {
 		free_io_pgtable_ops(pgtbl_ops);
+		return ret;
+	}
 
-	return ret;
+	smmu_domain->pgtbl_ops = pgtbl_ops;
+	return 0;
 }
 
 static __le64 *arm_smmu_get_step_for_sid(struct arm_smmu_device *smmu, u32 sid)

Hi,

Please consider applying the updated backport for 4.4-stable, below.

Thanks,
Jean

--- 8< ---

From: Jean-Philippe Brucker <[email protected]>
Date: Thu, 14 Dec 2017 11:03:01 +0000
Subject: [PATCH] iommu/arm-smmu-v3: Don't free page table ops twice

commit 57d72e159b60456c8bb281736c02ddd3164037aa upstream.

Kasan reports a double free when finalise_stage_fn fails: the io_pgtable ops are freed by arm_smmu_domain_finalise and then again by arm_smmu_domain_free. Prevent this by leaving pgtbl_ops empty on failure.

---
 drivers/iommu/arm-smmu-v3.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

index 64f1eb8fdcbc..347aaaa5a7ea 100644
@@ -1541,13 +1541,15 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain)
                return -ENOMEM;
 
        arm_smmu_ops.pgsize_bitmap = pgtbl_cfg.pgsize_bitmap;
-       smmu_domain->pgtbl_ops = pgtbl_ops;
 
        ret = finalise_stage_fn(smmu_domain, &pgtbl_cfg);
-       if (IS_ERR_VALUE(ret))
+       if (IS_ERR_VALUE(ret)) {
                free_io_pgtable_ops(pgtbl_ops);
+               return ret;
+       }
 
-       return ret;
+       smmu_domain->pgtbl_ops = pgtbl_ops;
+       return 0;
 }
 
 static struct arm_smmu_group *arm_smmu_group_get(struct device *dev)

--
2.15.1

This does not apply to the 4.4-stable tree:

checking file drivers/iommu/arm-smmu-v3.c
Hunk #1 FAILED at 1541.
1 out of 1 hunk FAILED

Are you sure you tried it?

thanks,

greg k-h

commit 57d72e159b60456c8bb281736c02ddd3164037aa upstream.

Kasan reports a double free when finalise_stage_fn fails: the io_pgtable ops are freed by arm_smmu_domain_finalise and then again by arm_smmu_domain_free. Prevent this by leaving pgtbl_ops empty on failure.

---

The whitespaces got corrupted last time, sorry about that. Let's hope this one works.

Thanks,
Jean

---
 drivers/iommu/arm-smmu-v3.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

index 64f1eb8fdcbc..347aaaa5a7ea 100644
@@ -1541,13 +1541,15 @@ static int arm_smmu_domain_finalise(struct iommu_domain *domain)
 		return -ENOMEM;
 
 	arm_smmu_ops.pgsize_bitmap = pgtbl_cfg.pgsize_bitmap;
-	smmu_domain->pgtbl_ops = pgtbl_ops;
 
 	ret = finalise_stage_fn(smmu_domain, &pgtbl_cfg);
-	if (IS_ERR_VALUE(ret))
+	if (IS_ERR_VALUE(ret)) {
 		free_io_pgtable_ops(pgtbl_ops);
+		return ret;
+	}
 
-	return ret;
+	smmu_domain->pgtbl_ops = pgtbl_ops;
+	return 0;
 }
 
 static struct arm_smmu_group *arm_smmu_group_get(struct device *dev)

2.15.1

It worked, thanks, now queued up.

greg k-h