CVE-2024-50133 LoongArch: Don't crash in stack_top() for tasks without vDSO
A null pointer dereference in the LoongArch Linux kernel causes a crash when tasks without vDSO call stack_top, leading to 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-2024-50133?
CVE-2024-50133 is a medium-severity vulnerability in Linux kernel, published on 5 Nov 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:
LoongArch: Don't crash in stack_top() for tasks without vDSO
Not all tasks have a vDSO mapped, for example kthreads never do. If such a task ever ends up calling stack_top(), it will derefence the NULL vdso pointer and crash.
This can for example happen when using kunit:
[<9000000000203874>] stack_top+0x58/0xa8 [<90000000002956cc>] arch_pick_mmap_layout+0x164/0x220 [<90000000003c284c>] kunit_vm_mmap_init+0x108/0x12c [<90000000003c1fbc>] __kunit_add_resource+0x38/0x8c [<90000000003c2704>] kunit_vm_mmap+0x88/0xc8 [<9000000000410b14>] usercopy_test_init+0xbc/0x25c [<90000000003c1db4>] kunit_try_run_case+0x5c/0x184 [<90000000003c3d54>] kunit_generic_run_threadfn_adapter+0x24/0x48 [<900000000022e4bc>] kthread+0xc8/0xd4 [<9000000000200ce8>] ret_from_kernel_thread+0xc/0xa4
Weakness: CWE-476
Which versions are affected by CVE-2024-50133?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-50133?
Apply the vendor's patch.
Is CVE-2024-50133 being exploited?
There is no known exploitation of CVE-2024-50133 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-52326, BELL-CVE-2024-50133, DEBIAN-CVE-2024-50133, GHSA-x3fm-x4jg-jw2h, UBUNTU-CVE-2024-50133.