Description
In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: prefer nft_chain_validate nft_chain_validate already performs loop detection because a cycle will result in a call stack overflow (ctx->level >= NFT_JUMP_STACK_SIZE). It also follows maps via ->validate callback in nft_lookup, so there appears no reason to iterate the maps again. nf_tables_check_loops() and all its helper functions can be removed. This improves ruleset load time significantly, from 23s down to 12s. This also fixes a crash bug. Old loop detection code can result in unbounded recursion: BUG: TASK stack guard page was hit at .... Oops: stack guard page: 0000 [#1] PREEMPT SMP KASAN CPU: 4 PID: 1539 Comm: nft Not tainted 6.10.0-rc5+ #1 [..] with a suitable ruleset during validation of register stores. I can't see any actual reason to attempt to check for this from nft_validate_register_store(), at this point the transaction is still in progress, so we don't have a full picture of the rule graph. For nf-next it might make sense to either remove it or make this depend on table->validate_state in case we could catch an error earlier (for improved error reporting to userspace).
Affected products
Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.
Linux Linux
Default version status: unaffected
20a69341f2d00cd042e81c82289fba8a13c05a25 to < 1947e4c3346faa8ac7e343652c0fd3b3e394202faffected20a69341f2d00cd042e81c82289fba8a13c05a25 to < cd4348e0a50286282c314ad6d2b0740e7c812c24affected20a69341f2d00cd042e81c82289fba8a13c05a25 to < 31c35f9f89ef585f1edb53e17ac73a0ca4a9712baffected20a69341f2d00cd042e81c82289fba8a13c05a25 to < 8246b7466c8da49d0d9e85e26cbd69dd6d3e3d1eaffected20a69341f2d00cd042e81c82289fba8a13c05a25 to < b6b6e430470e1c3c5513311cb35a15a205595abeaffected20a69341f2d00cd042e81c82289fba8a13c05a25 to < 717c91c6ed73e248de6a15bc53adefb81446c9d0affected20a69341f2d00cd042e81c82289fba8a13c05a25 to < 9df785aeb7dcc8efd1d4110bb27d26005298ebaeaffected20a69341f2d00cd042e81c82289fba8a13c05a25 to < cff3bd012a9512ac5ed858d38e6ed65f6391008caffected
Linux Linux
Default version status: affected
3.13affected0 to < 3.13unaffected4.19.320 to ≤ 4.19.*unaffected5.4.282 to ≤ 5.4.*unaffected5.10.224 to ≤ 5.10.*unaffected5.15.165 to ≤ 5.15.*unaffected6.1.105 to ≤ 6.1.*unaffected6.6.46 to ≤ 6.6.*unaffected6.9.10 to ≤ 6.9.*unaffected6.10 to ≤ *unaffected
References
- https://git.kernel.org/stable/c/1947e4c3346faa8ac7e343652c0fd3b3e394202f ↗
- https://git.kernel.org/stable/c/cd4348e0a50286282c314ad6d2b0740e7c812c24 ↗
- https://git.kernel.org/stable/c/31c35f9f89ef585f1edb53e17ac73a0ca4a9712b ↗
- https://git.kernel.org/stable/c/8246b7466c8da49d0d9e85e26cbd69dd6d3e3d1e ↗
- https://git.kernel.org/stable/c/b6b6e430470e1c3c5513311cb35a15a205595abe ↗
- https://git.kernel.org/stable/c/717c91c6ed73e248de6a15bc53adefb81446c9d0 ↗
- https://git.kernel.org/stable/c/9df785aeb7dcc8efd1d4110bb27d26005298ebae ↗
- https://git.kernel.org/stable/c/cff3bd012a9512ac5ed858d38e6ed65f6391008c ↗
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html ↗
- https://lists.debian.org/debian-lts-announce/2024/10/msg00003.html ↗