CVE-2022-48648: sfc: fix null pointer dereference in efx_hard_start_xmit

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2024-04-28 · updated 2026-06-17
Weakness: CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: sfc: fix null pointer dereference in efx_hard_start_xmit Trying to get the channel from the tx_queue variable here is wrong because we can only be here if tx_queue is NULL, so we shouldn't dereference it. As the above comment in the code says, this is very unlikely to happen, but it's wrong anyway so let's fix it. I hit this issue because of a different bug that caused tx_queue to be NULL. If that happens, this is the error message that we get here: BUG: unable to handle kernel NULL pointer dereference at 0000000000000020 [...] RIP: 0010:efx_hard_start_xmit+0x153/0x170 [sfc]

Affected products

Linux kernel: from 5.10 before 5.10.146; from 5.11 before 5.15.71; from 5.16 before 5.19.12; 6.0-rc1, 6.0-rc2, 6.0-rc3, 6.0-rc4, 6.0-rc5, 6.0-rc6 — fixed in 5.10.146, 5.15.71, 5.19.12

How to fix

Upgrade to a fixed version: Linux kernel 5.10.146, 5.15.71, 5.19.12. Check the vendor advisory for mitigations.

References

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