CVE-2022-48976
Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: flowtable_offload: fix using __this_cpu_add in preemptible flow_offload_queue_work() can be called in workqueue without bh disabled, like the call trace showed in my act_ct testing, calling NF_FLOW_TABLE_STAT_INC() there would cause a call trace: BUG: using __this_cpu_add() in preemptible [00000000] code: kworker/u4:0/138560 caller is flow_offload_queue_work+0xec/0x1b0 [nf_flow_table] Workqueue: act_ct_workqueue tcf_ct_flow_table_cleanup_work [act_ct] Call Trace: <TASK> dump_stack_lvl+0x33/0x46 check_preemption_disabled+0xc3/0xf0 flow_offload_queue_work+0xec/0x1b0 [nf_flow_table] nf_flow_table_iterate+0x138/0x170 [nf_flow_table] nf_flow_table_free+0x140/0x1a0 [nf_flow_table] tcf_ct_flow_table_cleanup_work+0x2f/0x2b0 [act_ct] process_one_work+0x6a3/0x1030 worker_thread+0x8a/0xdf0 This patch fixes it by using NF_FLOW_TABLE_STAT_INC_ATOMIC() instead in flow_offload_queue_work(). Note that for FLOW_CLS_REPLACE branch in flow_offload_queue_work(), it may not be called in preemptible path, but it's good to use NF_FLOW_TABLE_STAT_INC_ATOMIC() for all cases in flow_offload_queue_work().
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
No mitigations published for this CVE yet.
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OS impact
SUSE Affected 1 release
| Version | Status | Fixed in |
|---|---|---|
| — | Affected | — |
Debian Fixed 5 releases
| Version | Status | Fixed in |
|---|---|---|
| trixie | Fixed | 6.1.4-1 |
| sid | Fixed | 6.1.4-1 |
| forky | Fixed | 6.1.4-1 |
| bullseye | Fixed | 0 |
| bookworm | Fixed | 6.1.4-1 |
Red Hat Fixed 1 release
| Version | Status | Fixed in |
|---|---|---|
| 9 | Fixed | — |
References
Community-verified mitigations for this CVE will appear above when contributors publish them.
Verify integrity in audit chain (admin only). AS-IS.