CVE-2022-49378 sfc: fix considering that all channels have TX queues
A null pointer dereference in the sfc network driver causes a kernel crash when using separate TX channels, 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-2022-49378?
CVE-2022-49378 is a medium-severity vulnerability in Linux kernel, published on 26 Feb 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:
sfc: fix considering that all channels have TX queues
Normally, all channels have RX and TX queues, but this is not true if modparam efx_separate_tx_channels=1 is used. In that cases, some channels only have RX queues and others only TX queues (or more preciselly, they have them allocated, but not initialized).
Fix efx_channel_has_tx_queues to return the correct value for this case too.
Messages shown at probe time before the fix: sfc 0000:03:00.0 ens6f0np0: MC command 0x82 inlen 544 failed rc=-22 (raw=0) arg=0 ------------[ cut here ]------------ netdevice: ens6f0np0: failed to initialise TXQ -1 WARNING: CPU: 1 PID: 626 at drivers/net/ethernet/sfc/ef10.c:2393 efx_ef10_tx_init+0x201/0x300 [sfc] [...] stripped RIP: 0010:efx_ef10_tx_init+0x201/0x300 [sfc] [...] stripped Call Trace: efx_init_tx_queue+0xaa/0xf0 [sfc] efx_start_channels+0x49/0x120 [sfc] efx_start_all+0x1f8/0x430 [sfc] efx_net_open+0x5a/0xe0 [sfc] __dev_open+0xd0/0x190 __dev_change_flags+0x1b3/0x220 dev_change_flags+0x21/0x60 [...] stripped
Messages shown at remove time before the fix: sfc 0000:03:00.0 ens6f0np0: failed to flush 10 queues sfc 0000:03:00.0 ens6f0np0: failed to flush queues
Which versions are affected by CVE-2022-49378?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2022-49378?
Apply the vendor's patch.
Is CVE-2022-49378 being exploited?
There is no known exploitation of CVE-2022-49378 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as DEBIAN-CVE-2022-49378, GHSA-6gpm-qxpm-qmwf, UBUNTU-CVE-2022-49378.