CVE-2024-26786 iommufd: Fix iopt_access_list_id overwrite bug
A local attacker can trigger a kernel warning and potential crash in the iommufd subsystem due to an ID overwrite bug, causing 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-2024-26786?
CVE-2024-26786 is a high-severity vulnerability in Linux kernel, published on 4 Apr 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:
iommufd: Fix iopt_access_list_id overwrite bug
Syzkaller reported the following WARN_ON: WARNING: CPU: 1 PID: 4738 at drivers/iommu/iommufd/io_pagetable.c:1360
Call Trace: iommufd_access_change_ioas+0x2fe/0x4e0 iommufd_access_destroy_object+0x50/0xb0 iommufd_object_remove+0x2a3/0x490 iommufd_object_destroy_user iommufd_access_destroy+0x71/0xb0 iommufd_test_staccess_release+0x89/0xd0 __fput+0x272/0xb50 __fput_sync+0x4b/0x60 __do_sys_close __se_sys_close __x64_sys_close+0x8b/0x110 do_syscall_x64
The mismatch between the access pointer in the list and the passed-in pointer is resulting from an overwrite of access->iopt_access_list_id, in iopt_add_access(). Called from iommufd_access_change_ioas() when xa_alloc() succeeds but iopt_calculate_iova_alignment() fails.
Add a new_id in iopt_add_access() and only update iopt_access_list_id when returning successfully.
Weakness: CWE-476
Which versions are affected by CVE-2024-26786?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-26786?
Apply the vendor's patch.
Is CVE-2024-26786 being exploited?
There is no known exploitation of CVE-2024-26786 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2024-26786, DEBIAN-CVE-2024-26786, GHSA-jv67-jxg9-q8v4, UBUNTU-CVE-2024-26786.