CVE-2024-41042

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).

• linux linux kernel (>= 3.13 < 4.19.320) • linux linux kernel (>= 4.20 < 5.4.282) • linux linux kernel (>= 5.5 < 5.10.224) • linux linux kernel (>= 5.11 < 5.15.165) • linux linux kernel (>= 5.16 < 6.1.105) • linux linux kernel (>= 6.2 < 6.6.46) • linux linux kernel (>= 6.7 < 6.9.10) • linux linux kernel 6.10