CVE-2023-52910 iommu/iova: Fix alloc iova overflows issue
An integer overflow in the Linux kernel IOMMU allocator can cause incorrect memory allocation, potentially leading to system instability or denial of service.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-52910?
CVE-2023-52910 is a high-severity vulnerability in Linux kernel, published on 21 Aug 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
iommu/iova: Fix alloc iova overflows issue
In __alloc_and_insert_iova_range, there is an issue that retry_pfn overflows. The value of iovad->anchor.pfn_hi is ~0UL, then when iovad->cached_node is iovad->anchor, curr_iova->pfn_hi + 1 will overflow. As a result, if the retry logic is executed, low_pfn is updated to 0, and then new_pfn < low_pfn returns false to make the allocation successful.
This issue occurs in the following two situations: 1. The first iova size exceeds the domain size. When initializing iova domain, iovad->cached_node is assigned as iovad->anchor. For example, the iova domain size is 10M, start_pfn is 0x1_F000_0000, and the iova size allocated for the first time is 11M. The following is the log information, new->pfn_lo is smaller than iovad->cached_node.
Example log as follows: [ 223.798112][T1705487] sh: [name:iova&]__alloc_and_insert_iova_range start_pfn:0x1f0000,retry_pfn:0x0,size:0xb00,limit_pfn:0x1f0a00 [ 223.799590][T1705487] sh: [name:iova&]__alloc_and_insert_iova_range success start_pfn:0x1f0000,new->pfn_lo:0x1efe00,new->pfn_hi:0x1f08ff
2. The node with the largest iova->pfn_lo value in the iova domain is deleted, iovad->cached_node will be updated to iovad->anchor, and then the alloc iova size exceeds the maximum iova size that can be allocated in the domain.
After judging that retry_pfn is less than limit_pfn, call retry_pfn+1 to fix the overflow issue.
Which versions are affected by CVE-2023-52910?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2023-52910?
Apply the vendor's patch.
Is CVE-2023-52910 being exploited?
There is no known exploitation of CVE-2023-52910 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2023-52910, DEBIAN-CVE-2023-52910, GHSA-f5pw-c669-x4x7, UBUNTU-CVE-2023-52910.