CVE-2025-39911 i40e: fix IRQ freeing in i40e_vsi_request_irq_msix error path
A bug in the i40e network driver error path causes incorrect IRQ freeing, leading to kernel warnings and potential instability during interface configuration.
- 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-2025-39911?
CVE-2025-39911 is a high-severity vulnerability in Debian Debian Linux, published on 1 Oct 2025. 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:
i40e: fix IRQ freeing in i40e_vsi_request_irq_msix error path
If request_irq() in i40e_vsi_request_irq_msix() fails in an iteration later than the first, the error path wants to free the IRQs requested so far. However, it uses the wrong dev_id argument for free_irq(), so it does not free the IRQs correctly and instead triggers the warning:
Trying to free already-free IRQ 173 WARNING: CPU: 25 PID: 1091 at kernel/irq/manage.c:1829 __free_irq+0x192/0x2c0 Modules linked in: i40e(+) [...] CPU: 25 UID: 0 PID: 1091 Comm: NetworkManager Not tainted 6.17.0-rc1+ #1 PREEMPT(lazy) Hardware name: [...] RIP: 0010:__free_irq+0x192/0x2c0 [...] Call Trace: <TASK> free_irq+0x32/0x70 i40e_vsi_request_irq_msix.cold+0x63/0x8b [i40e] i40e_vsi_request_irq+0x79/0x80 [i40e] i40e_vsi_open+0x21f/0x2f0 [i40e] i40e_open+0x63/0x130 [i40e] __dev_open+0xfc/0x210 __dev_change_flags+0x1fc/0x240 netif_change_flags+0x27/0x70 do_setlink.isra.0+0x341/0xc70 rtnl_newlink+0x468/0x860 rtnetlink_rcv_msg+0x375/0x450 netlink_rcv_skb+0x5c/0x110 netlink_unicast+0x288/0x3c0 netlink_sendmsg+0x20d/0x430 ____sys_sendmsg+0x3a2/0x3d0 ___sys_sendmsg+0x99/0xe0 __sys_sendmsg+0x8a/0xf0 do_syscall_64+0x82/0x2c0 entry_SYSCALL_64_after_hwframe+0x76/0x7e [...] </TASK> ---[ end trace 0000000000000000 ]---
Use the same dev_id for free_irq() as for request_irq().
I tested this with inserting code to fail intentionally.
Which versions are affected by CVE-2025-39911?
It affects 2 products.
Products include Debian Debian Linux, Linux kernel.
How do I fix CVE-2025-39911?
Apply the vendor's patch.
Is CVE-2025-39911 being exploited?
There is no known exploitation of CVE-2025-39911 in the wild and no public exploit code.
Other vulnerabilities in Debian Debian Linux
Sources
Also known as AZL-68043, AZL-74754, BELL-CVE-2025-39911, DEBIAN-CVE-2025-39911, GHSA-53x5-9xgx-8wwp, ROOT-OS-DEBIAN-11-CVE-2025-39911 and 3 more.