Bug 1223508 (CVE-2022-48645)

Summary: VUL-0: CVE-2022-48645: kernel: net: enetc: deny offload of tc-based TSN features on VF interfaces
Product: [Novell Products] SUSE Security Incidents Reporter: SMASH SMASH <smash_bz>
Component: IncidentsAssignee: Denis Kirjanov <denis.kirjanov>
Status: NEW --- QA Contact: Security Team bot <security-team>
Severity: Normal    
Priority: P3 - Medium CC: rfrohl, vasant.karasulli
Version: unspecified   
Target Milestone: ---   
Hardware: Other   
OS: Other   
URL: https://smash.suse.de/issue/403402/
Whiteboard: CVSSv3.1:SUSE:CVE-2022-48645:5.5:(AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
Found By: Security Response Team Services Priority:
Business Priority: Blocker: ---
Marketing QA Status: --- IT Deployment: ---

Description SMASH SMASH 2024-04-29 10:11:25 UTC 
In the Linux kernel, the following vulnerability has been resolved:

net: enetc: deny offload of tc-based TSN features on VF interfaces

TSN features on the ENETC (taprio, cbs, gate, police) are configured
through a mix of command BD ring messages and port registers:
enetc_port_rd(), enetc_port_wr().

Port registers are a region of the ENETC memory map which are only
accessible from the PCIe Physical Function. They are not accessible from
the Virtual Functions.

Moreover, attempting to access these registers crashes the kernel:

$ echo 1 > /sys/bus/pci/devices/0000\:00\:00.0/sriov_numvfs
pci 0000:00:01.0: [1957:ef00] type 00 class 0x020001
fsl_enetc_vf 0000:00:01.0: Adding to iommu group 15
fsl_enetc_vf 0000:00:01.0: enabling device (0000 -> 0002)
fsl_enetc_vf 0000:00:01.0 eno0vf0: renamed from eth0
$ tc qdisc replace dev eno0vf0 root taprio num_tc 8 map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 base-time 0 \
	sched-entry S 0x7f 900000 sched-entry S 0x80 100000 flags 0x2
Unable to handle kernel paging request at virtual address ffff800009551a08
Internal error: Oops: 96000007 [#1] PREEMPT SMP
pc : enetc_setup_tc_taprio+0x170/0x47c
lr : enetc_setup_tc_taprio+0x16c/0x47c
Call trace:
 enetc_setup_tc_taprio+0x170/0x47c
 enetc_setup_tc+0x38/0x2dc
 taprio_change+0x43c/0x970
 taprio_init+0x188/0x1e0
 qdisc_create+0x114/0x470
 tc_modify_qdisc+0x1fc/0x6c0
 rtnetlink_rcv_msg+0x12c/0x390

Split enetc_setup_tc() into separate functions for the PF and for the
VF drivers. Also remove enetc_qos.o from being included into
enetc-vf.ko, since it serves absolutely no purpose there.

References:
http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2022-48645
https://www.cve.org/CVERecord?id=CVE-2022-48645
https://git.kernel.org/stable/c/23022b74b1a23bed044f6bc96cf92f6ca5f3e75f
https://git.kernel.org/stable/c/510e703e4ed0e011db860bc21228aff48fc9eea7
https://git.kernel.org/stable/c/5641c751fe2f92d3d9e8a8e03c1263ac8caa0b42
https://git.kernel.org/pub/scm/linux/security/vulns.git/plain/cve/published/2022/CVE-2022-48645.mbox