kevin/linux
1
Fork 0
Code

netfilter: nft_set_pipapo_avx2: disable softinterrupts

Browse Source 
We need to disable softinterrupts, else we get following problem:

1. pipapo_avx2 called from process context; fpu usable
2. preempt_disable() called, pcpu scratchmap in use
3. softirq handles rx or tx, we re-enter pipapo_avx2
4. fpu busy, fallback to generic non-avx version
5. fallback reuses scratch map and index, which are in use
   by the preempted process

Handle this same way as generic version by first disabling
softinterrupts while the scratchmap is in use.

Fixes: f0b3d33806 ("netfilter: nft_set_pipapo_avx2: Add irq_fpu_usable() check, fallback to non-AVX2 version")
Cc: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2024-07-19 13:19:26 +02:00 committed by Pablo Neira Ayuso
parent 3ba359c0cd
commit a16909ae99
1 changed files with 10 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
net/netfilter/nft_set_pipapo_avx2.c
View File

@ -1139,8 +1139,14 @@ bool nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
bool map_index;
int i, ret = 0;
if (unlikely(!irq_fpu_usable()))
return nft_pipapo_lookup(net, set, key, ext);
local_bh_disable();
if (unlikely(!irq_fpu_usable())) {
bool fallback_res = nft_pipapo_lookup(net, set, key, ext);
local_bh_enable();
return fallback_res;
}
m = rcu_dereference(priv->match);
@ -1155,6 +1161,7 @@ bool nft_pipapo_avx2_lookup(const struct net *net, const struct nft_set *set,
scratch = *raw_cpu_ptr(m->scratch);
if (unlikely(!scratch)) {
kernel_fpu_end();
local_bh_enable();
return false;
}
@ -1235,6 +1242,7 @@ out:
if (i % 2)
scratch->map_index = !map_index;
kernel_fpu_end();
local_bh_enable();
return ret >= 0;
}