UBUNTU-CVE-2024-38610
In the Linux kernel, the following vulnerability has been resolved: drivers/virt/acrn: fix PFNMAP PTE checks in acrn_vm_ram_map() Patch series "mm: follow_pte() improvements and acrn follow_pte() fixes". Patch #1 fixes a bunch of issues I spotted in the acrn driver. It compiles, that's all I know. I'll appreciate some review and testing from acrn folks. Patch #2+#3 improve follow_pte(), passing a VMA instead of the MM, adding more sanity checks, and improving the documentation. Gave it a quick test on x86-64 using VM_PAT that ends up using follow_pte(). This patch (of 3): We currently miss handling various cases, resulting in a dangerous follow_pte() (previously follow_pfn()) usage. (1) We're not checking PTE write permissions. Maybe we should simply always require pte_write() like we do for pin_user_pages_fast(FOLL_WRITE)? Hard to tell, so let's check for ACRN_MEM_ACCESS_WRITE for now. (2) We're not rejecting refcounted pages. As we are not using MMU notifiers, messing with refcounted pages is dangerous and can result in use-after-free. Let's make sure to reject them. (3) We are only looking at the first PTE of a bigger range. We only lookup a single PTE, but memmap->len may span a larger area. Let's loop over all involved PTEs and make sure the PFN range is actually contiguous. Reject everything else: it couldn't have worked either way, and rather made use access PFNs we shouldn't be accessing.
02 / AFFECTED SOFTWARE
Affected packages
37 explicit affected versions
7 explicit affected versions
13 explicit affected versions
2 explicit affected versions
5 explicit affected versions
11 explicit affected versions
35 explicit affected versions
10 explicit affected versions
10 explicit affected versions
49 explicit affected versions
50 explicit affected versions
6 explicit affected versions
12 explicit affected versions
54 explicit affected versions
19 explicit affected versions
6 explicit affected versions
58 explicit affected versions
8 explicit affected versions
44 explicit affected versions
44 explicit affected versions
10 explicit affected versions
1 explicit affected versions
7 explicit affected versions
51 explicit affected versions
7 explicit affected versions
50 explicit affected versions
2 explicit affected versions
13 explicit affected versions
4 explicit affected versions
35 explicit affected versions
11 explicit affected versions
16 explicit affected versions
18 explicit affected versions
12 explicit affected versions
13 explicit affected versions
4 explicit affected versions
23 explicit affected versions
11 explicit affected versions
21 explicit affected versions
16 explicit affected versions
9 explicit affected versions
7 explicit affected versions
12 explicit affected versions
42 explicit affected versions
12 explicit affected versions
14 explicit affected versions
7 explicit affected versions
12 explicit affected versions
12 explicit affected versions
31 explicit affected versions
2 explicit affected versions
11 explicit affected versions
3 explicit affected versions
37 explicit affected versions
13 explicit affected versions
1 explicit affected versions
26 explicit affected versions
13 explicit affected versions
6 explicit affected versions
29 explicit affected versions
13 explicit affected versions
55 explicit affected versions
1 explicit affected versions
2 explicit affected versions
53 explicit affected versions
15 explicit affected versions
33 explicit affected versions
23 explicit affected versions
10 explicit affected versions
1 explicit affected versions
11 explicit affected versions
12 explicit affected versions
7 explicit affected versions
12 explicit affected versions
42 explicit affected versions
36 explicit affected versions
52 explicit affected versions
10 explicit affected versions
26 explicit affected versions
9 explicit affected versions
9 explicit affected versions
1 explicit affected versions
2 explicit affected versions
10 explicit affected versions
13 explicit affected versions
16 explicit affected versions
55 explicit affected versions
10 explicit affected versions
43 explicit affected versions
3 explicit affected versions
2 explicit affected versions
51 explicit affected versions
7 explicit affected versions
12 explicit affected versions
41 explicit affected versions
27 explicit affected versions
27 explicit affected versions
3 explicit affected versions
8 explicit affected versions
16 explicit affected versions
5 explicit affected versions
8 explicit affected versions
10 explicit affected versions
6 explicit affected versions
26 explicit affected versions
13 explicit affected versions
7 explicit affected versions
46 explicit affected versions
10 explicit affected versions
13 explicit affected versions
12 explicit affected versions
44 explicit affected versions
16 explicit affected versions
3 explicit affected versions
13 explicit affected versions
41 explicit affected versions
37 explicit affected versions
10 explicit affected versions
14 explicit affected versions
38 explicit affected versions
44 explicit affected versions
9 explicit affected versions
44 explicit affected versions
11 explicit affected versions
52 explicit affected versions
7 explicit affected versions
25 explicit affected versions
4 explicit affected versions
1 explicit affected versions
1 explicit affected versions
50 explicit affected versions
13 explicit affected versions
43 explicit affected versions
10 explicit affected versions
8 explicit affected versions
14 explicit affected versions
4 explicit affected versions
11 explicit affected versions
1 explicit affected versions
3 explicit affected versions
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
In the Linux kernel, the following vulnerability has been resolved: drivers/virt/acrn: fix PFNMAP PTE checks in acrn_vm_ram_map() Patch series "mm: follow_pte() improvements and acrn follow_pte() fixes". Patch #1 fixes a bunch of issues I spotted in the acrn driver. It compiles, that's all I know. I'll appreciate some review and testing from acrn folks. Patch #2+#3 improve follow_pte(), passing a VMA instead of the MM, adding more sanity checks, and improving the documentation. Gave it a quick test on x86-64 using VM_PAT that ends up using follow_pte(). This patch (of 3): We currently miss handling various cases, resulting in a dangerous follow_pte() (previously follow_pfn()) usage. (1) We're not checking PTE write permissions. Maybe we should simply always require pte_write() like we do for pin_user_pages_fast(FOLL_WRITE)? Hard to tell, so let's check for ACRN_MEM_ACCESS_WRITE for now. (2) We're not rejecting refcounted pages. As we are not using MMU notifiers, messing with refcounted pages is dangerous and can result in use-after-free. Let's make sure to reject them. (3) We are only looking at the first PTE of a bigger range. We only lookup a single PTE, but memmap->len may span a larger area. Let's loop over all involved PTEs and make sure the PFN range is actually contiguous. Reject everything else: it couldn't have worked either way, and rather made use access PFNs we shouldn't be accessing.
05 / REFERENCES
Further evidence
- https://git.kernel.org/linus/3d6586008f7b638f91f3332602592caa8b00b559
- https://git.kernel.org/stable/c/2c8d6e24930b8ef7d4a81787627c559ae0e0d3bb
- https://git.kernel.org/stable/c/3d6586008f7b638f91f3332602592caa8b00b559
- https://git.kernel.org/stable/c/4c4ba3cf3a15ccfbaf787d0296fa42cdb00da9b4
- https://git.kernel.org/stable/c/5c6705aa47b5b78d7ad36fea832bb69caa5bf49a
- https://git.kernel.org/stable/c/afeb0e69627695f759fc73c39c1640dbf8649b32
- https://git.kernel.org/stable/c/e873f36ec890bece26ecce850e969917bceebbb6
- https://ubuntu.com/security/CVE-2024-38610
- https://ubuntu.com/security/notices/USN-6949-1
- https://ubuntu.com/security/notices/USN-6949-2
- https://ubuntu.com/security/notices/USN-6952-1
- https://ubuntu.com/security/notices/USN-6952-2
- https://ubuntu.com/security/notices/USN-6955-1
- https://ubuntu.com/security/notices/USN-7007-1
- https://ubuntu.com/security/notices/USN-7007-2
- https://ubuntu.com/security/notices/USN-7007-3
- https://ubuntu.com/security/notices/USN-7009-1
- https://ubuntu.com/security/notices/USN-7009-2
- https://ubuntu.com/security/notices/USN-7019-1
- https://www.cve.org/CVERecord?id=CVE-2024-38610