Description (CNA)
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.
Affected (CNA)
| Vendor / product | Versions |
|---|---|
| Linux / Linux | affected f22954f8c58fd5f5489f5980796914e306757e77 before 3325628cb36b7f216c5716e7b5124d9dc81199e4; affected 41841b585e53babdfb0fa6fdfa54f6d7c28c1206 before 4c06c13317b9a08decedcd7aaf706691e336277c; affected 2c9f0293280e258606e54ed2b96fa71498432eae before 55a40406aac555defe9bdd0adec9508116ce7cb1; affected 2c9f0293280e258606e54ed2b96fa71498432eae before 09e650c3a3a7d804430260510534ccbf71c75b2e; affected 2c9f0293280e258606e54ed2b96fa71498432eae before 9f6958ba2e902f9820c594869bd710ba74b7c4c0; affected 4167aa477abcf62b0dfda51f3513280fa73cd588; affected 5.15.129 before 5.15.163; affected 6.1.50 before 6.1.98; affected 6.4.13 before 6.5 |
| Linux / Linux | affected 6.5; unaffected 0 before 6.5; unaffected 5.15.163 through 5.15.*; unaffected 6.1.98 through 6.1.*; unaffected 6.6.39 through 6.6.*; unaffected 6.9.9 through 6.9.*; unaffected 6.10 through * |
CWE
No CWE identifiers supplied.
References
- https://git.kernel.org/stable/c/3325628cb36b7f216c5716e7b5124d9dc81199e4
- https://git.kernel.org/stable/c/4c06c13317b9a08decedcd7aaf706691e336277c
- https://git.kernel.org/stable/c/55a40406aac555defe9bdd0adec9508116ce7cb1
- https://git.kernel.org/stable/c/09e650c3a3a7d804430260510534ccbf71c75b2e
- https://git.kernel.org/stable/c/9f6958ba2e902f9820c594869bd710ba74b7c4c0
ADP enrichment
No English description supplied.
- https://git.kernel.org/stable/c/3325628cb36b7f216c5716e7b5124d9dc81199e4
- https://git.kernel.org/stable/c/4c06c13317b9a08decedcd7aaf706691e336277c
- https://git.kernel.org/stable/c/55a40406aac555defe9bdd0adec9508116ce7cb1
- https://git.kernel.org/stable/c/09e650c3a3a7d804430260510534ccbf71c75b2e
- https://git.kernel.org/stable/c/9f6958ba2e902f9820c594869bd710ba74b7c4c0
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
No English description supplied.
No references supplied.