net: enetc: Do not configure preemptible TCs if SIs do not support
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: partial
Summary
In the Linux kernel, the following vulnerability has been resolved: net: enetc: Do not configure preemptible TCs if SIs do not support Both ENETC PF and VF drivers share enetc_setup_tc_mqprio() to configure MQPRIO. And enetc_setup_tc_mqprio() calls enetc_change_preemptible_tcs() to configure preemptible TCs. However, only PF is able to configure preemptible TCs. Because only PF has related registers, while VF does not have these registers. So for VF, its hw->port pointer is NULL. Therefore, VF will access an invalid pointer when accessing a non-existent register, which will cause a crash issue. The simplified log is as follows. root@ls1028ardb:~# tc qdisc add dev eno0vf0 parent root handle 100: \ mqprio num_tc 4 map 0 0 1 1 2 2 3 3 queues 1@0 1@1 1@2 1@3 hw 1 [ 187.290775] Unable to handle kernel paging request at virtual address 0000000000001f00 [ 187.424831] pc : enetc_mm_commit_preemptible_tcs+0x1c4/0x400 [ 187.430518] lr : enetc_mm_commit_preemptible_tcs+0x30c/0x400 [ 187.511140] Call trace: [ 187.513588] enetc_mm_commit_preemptible_tcs+0x1c4/0x400 [ 187.518918] enetc_setup_tc_mqprio+0x180/0x214 [ 187.523374] enetc_vf_setup_tc+0x1c/0x30 [ 187.527306] mqprio_enable_offload+0x144/0x178 [ 187.531766] mqprio_init+0x3ec/0x668 [ 187.535351] qdisc_create+0x15c/0x488 [ 187.539023] tc_modify_qdisc+0x398/0x73c [ 187.542958] rtnetlink_rcv_msg+0x128/0x378 [ 187.547064] netlink_rcv_skb+0x60/0x130 [ 187.550910] rtnetlink_rcv+0x18/0x24 [ 187.554492] netlink_unicast+0x300/0x36c [ 187.558425] netlink_sendmsg+0x1a8/0x420 [ 187.606759] ---[ end trace 0000000000000000 ]--- In addition, some PFs also do not support configuring preemptible TCs, such as eno1 and eno3 on LS1028A. It won't crash like it does for VFs, but we should prevent these PFs from accessing these unimplemented registers.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- Linux Linux
Version range not reported
- Linux Linux
6.4