In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: unconditionally flush pending work before notifier syzbot reports: KASAN: slab-uaf in nft_ctx_update include/net/netfilter/nf_tables.h:1831 KASAN: slab-uaf in nft_commit_release net/netfilter/nf_tables_api.c:9530 KASAN: slab-uaf int nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597 Read of size 2 at addr ffff88802b0051c4 by task kworker/1:1/45 [..] Workqueue: events nf_tables_trans_destroy_work Call Trace: nft_ctx_update include/net/netfilter/nf_tables.h:1831 [inline] nft_commit_release net/netfilter/nf_tables_api.c:9530 [inline] nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597 Problem is that the notifier does a conditional flush, but its possible that the table-to-be-removed is still referenced by transactions being processed by the worker, so we need to flush unconditionally. We could make the flush_work depend on whether we found a table to delete in nf-next to avoid the flush for most cases. AFAICS this problem is only exposed in nf-next, with commit e169285f8c56 ("netfilter: nf_tables: do not store nft_ctx in transaction objects"), with this commit applied there is an unconditional fetch of table->family which is whats triggering the above splat.
History

Thu, 12 Sep 2024 02:30:00 +0000

Type Values Removed Values Added
Weaknesses CWE-416

Wed, 11 Sep 2024 13:30:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 27 Aug 2024 14:00:00 +0000

Type Values Removed Values Added
First Time appeared Linux
Linux linux Kernel
Weaknesses NVD-CWE-noinfo
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel

cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published: 2024-07-30T07:46:04.194Z

Updated: 2024-09-11T17:33:06.893Z

Reserved: 2024-07-29T15:50:41.176Z

Link: CVE-2024-42109

cve-icon Vulnrichment

Updated: 2024-09-11T12:42:14.593Z

cve-icon NVD

Status : Analyzed

Published: 2024-07-30T08:15:03.407

Modified: 2024-08-27T13:44:00.143

Link: CVE-2024-42109

cve-icon Redhat

Severity : Low

Publid Date: 2024-07-30T00:00:00Z

Links: CVE-2024-42109 - Bugzilla