CVEvulnerability
CVE-2026-89926
- Status
- Received
- Published
- 2026-09-16
- Last modified
- 2026-10-19
- Assigner
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Description
In the Linux kernel, the following vulnerability has been resolved:
KVM: s390: Fix length check __import_wp_info()
struct kvm_hw_breakpoint::len is a __u64 that is fully controlled by user
space. This is then assigned to wp_info->len, which is an int. The bounds
check is done on the truncated value while the allocation uses the
untruncated one:
wp_info->len = bp_data->len;
[...]
if (wp_info->len < 0 || wp_info->len > MAX_WP_SIZE)
return -EINVAL;
wp_info->old_data = kmalloc(bp_data->len, GFP_KERNEL_ACCOUNT);
Use the validated value for the allocation as intended. Without this
fix userspace can trigger >4GB allocations which will fail and result
in a WARN due to MAX_PAGE_ORDER.
References
- https://git.kernel.org/stable/c/3fe801db90bdeefb0bbdda42d832846b53f64f8a git.kernel.org
- https://git.kernel.org/stable/c/4c07680a467e2f7697245bcd11691bffb2a6f0ed git.kernel.org
- https://git.kernel.org/stable/c/71153d3262517e1c02c3a66aa5094f279b2d1454 git.kernel.org
- https://git.kernel.org/stable/c/aef540194effd768bed0bd2e6a74fe135a3d7c3a git.kernel.org
- https://git.kernel.org/stable/c/b94ab9caa5d72c78226121cccff5e33f946da900 git.kernel.org
- https://git.kernel.org/stable/c/beb9c55af609c4c7308259d7191688c75a4e3d4a git.kernel.org
- https://git.kernel.org/stable/c/fec89d327d9b2b669b5bbdac209386c6317c3722 git.kernel.org