CVE-2024-42082 xdp: Remove WARN() from __xdp_reg_mem_model()
A local attacker can trigger a kernel warning via BPF XDP tests, potentially causing 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-2024-42082?
CVE-2024-42082 is a medium-severity denial of service vulnerability in Linux kernel, published on 29 Jul 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:
xdp: Remove WARN() from __xdp_reg_mem_model()
syzkaller reports a warning in __xdp_reg_mem_model().
The warning occurs only if __mem_id_init_hash_table() returns an error. It returns the error in two cases:
1. memory allocation fails; 2. rhashtable_init() fails when some fields of rhashtable_params struct are not initialized properly.
The second case cannot happen since there is a static const rhashtable_params struct with valid fields. So, warning is only triggered when there is a problem with memory allocation.
Thus, there is no sense in using WARN() to handle this error and it can be safely removed.
WARNING: CPU: 0 PID: 5065 at net/core/xdp.c:299 __xdp_reg_mem_model+0x2d9/0x650 net/core/xdp.c:299
CPU: 0 PID: 5065 Comm: syz-executor883 Not tainted 6.8.0-syzkaller-05271-gf99c5f563c17 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 RIP: 0010:__xdp_reg_mem_model+0x2d9/0x650 net/core/xdp.c:299
Call Trace: xdp_reg_mem_model+0x22/0x40 net/core/xdp.c:344 xdp_test_run_setup net/bpf/test_run.c:188 [inline] bpf_test_run_xdp_live+0x365/0x1e90 net/bpf/test_run.c:377 bpf_prog_test_run_xdp+0x813/0x11b0 net/bpf/test_run.c:1267 bpf_prog_test_run+0x33a/0x3b0 kernel/bpf/syscall.c:4240 __sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5649 __do_sys_bpf kernel/bpf/syscall.c:5738 [inline] __se_sys_bpf kernel/bpf/syscall.c:5736 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5736 do_syscall_64+0xfb/0x240 entry_SYSCALL_64_after_hwframe+0x6d/0x75
Found by Linux Verification Center (linuxtesting.org) with syzkaller.
Weakness: CWE-770
Which versions are affected by CVE-2024-42082?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-42082?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2024-42082 being exploited?
There is no known exploitation of CVE-2024-42082 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-47148, BELL-CVE-2024-42082, DEBIAN-CVE-2024-42082, GHSA-p649-hp44-fr85, UBUNTU-CVE-2024-42082.