CVE-2022-48647 sfc: fix TX channel offset when using legacy interrupts
A null pointer dereference in the sfc network driver causes a kernel crash when sending traffic in legacy interrupt mode with specific channel configurations.
- 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-2022-48647?
CVE-2022-48647 is a medium-severity vulnerability in Linux kernel, published on 28 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:
sfc: fix TX channel offset when using legacy interrupts
In legacy interrupt mode the tx_channel_offset was hardcoded to 1, but that's not correct if efx_sepparate_tx_channels is false. In that case, the offset is 0 because the tx queues are in the single existing channel at index 0, together with the rx queue.
Without this fix, as soon as you try to send any traffic, it tries to get the tx queues from an uninitialized channel getting these errors: WARNING: CPU: 1 PID: 0 at drivers/net/ethernet/sfc/tx.c:540 efx_hard_start_xmit+0x12e/0x170 [sfc] [...] RIP: 0010:efx_hard_start_xmit+0x12e/0x170 [sfc] [...] Call Trace: <IRQ> dev_hard_start_xmit+0xd7/0x230 sch_direct_xmit+0x9f/0x360 __dev_queue_xmit+0x890/0xa40 [...] BUG: unable to handle kernel NULL pointer dereference at 0000000000000020 [...] RIP: 0010:efx_hard_start_xmit+0x153/0x170 [sfc] [...] Call Trace: <IRQ> dev_hard_start_xmit+0xd7/0x230 sch_direct_xmit+0x9f/0x360 __dev_queue_xmit+0x890/0xa40 [...]
Weakness: CWE-476
Which versions are affected by CVE-2022-48647?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-48647?
Apply the vendor's patch.
Is CVE-2022-48647 being exploited?
There is no known exploitation of CVE-2022-48647 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-48647, GHSA-xxhf-v2m2-422x, UBUNTU-CVE-2022-48647.