[PATCH 1/1] iommu/amd: Fix memory leak in alloc_pci_segment()

[PATCH 1/1] iommu/amd: Fix memory leak in alloc_pci_segment()

[Kun(llfl)]

Fix the memory leak issue that occurs when resource allocation fails in
alloc_pci_segment(). The dev_table, alias_table, and rlookup_table were
introduced individually in commits 04230c119930, 99fc4ac3d297,
and eda797a27795, but they all fail to release allocated resources
when other allocations fail.

Fixes: 04230c119930 ("iommu/amd: Introduce per PCI segment device table")
Reported-by: Xuchun Shang <xuchun.shang@linux.alibaba.com>
Signed-off-by: Kun(llfl) <llfl@linux.alibaba.com>
---
 drivers/iommu/amd/init.c | 15 ++++++++++++---
 1 file changed, 12 insertions(+), 3 deletions(-)

diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index ac6754a85f35..4ce567f39473 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -1642,13 +1642,22 @@ static struct amd_iommu_pci_seg *__init alloc_pci_segment(u16 id,
 	list_add_tail(&pci_seg->list, &amd_iommu_pci_seg_list);
 
 	if (alloc_dev_table(pci_seg))
-		return NULL;
+		goto alloc_dev_fail;
 	if (alloc_alias_table(pci_seg))
-		return NULL;
+		goto alloc_alias_fail;
 	if (alloc_rlookup_table(pci_seg))
-		return NULL;
+		goto alloc_rlookup_fail;
 
 	return pci_seg;
+
+alloc_rlookup_fail:
+	free_rlookup_table(pci_seg);
+alloc_alias_fail:
+	free_alias_table(pci_seg);
+alloc_dev_fail:
+	free_dev_table(pci_seg);
+	kfree(pci_seg);
+	return NULL;
 }
 
 static struct amd_iommu_pci_seg *__init get_pci_segment(u16 id,
-- 
2.43.0

Re: [PATCH] iommu/amd: Fix memory leak in alloc_pci_segment()

[Markus Elfring]

> Fix the memory leak issue that occurs when resource allocation fails in
> alloc_pci_segment(). The dev_table, alias_table, and rlookup_table were
> introduced individually in commits 04230c119930, 99fc4ac3d297,
> and eda797a27795, but they all fail to release allocated resources
> when other allocations fail.
…

Please refer not only to commit hashes.
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/Documentation/process/submitting-patches.rst?h=v6.9-rc5#n99

Would you like to extend the change description (with an enumeration)?

Regards,
Markus