netfilter: nft_set_pipapo_avx2: add missing vzeroupper

Since pipapo_get_avx2() uses YMM registers, execute vzeroupper before
returning from it.  This is needed to avoid degrading the performance of
any later SSE code that may happen to be executed.

Fixes: 7400b063969b ("nft_set_pipapo: Introduce AVX2-based lookup implementation")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@kernel.org>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nft_set_pipapo_avx2.c b/net/netfilter/nft_set_pipapo_avx2.c
index b3f105520a85bdd8d7db150860b04fb4e006ee91..21f5be68c703694ce4372f25aa06945e5475ec3c 100644 (file)
--- a/net/netfilter/nft_set_pipapo_avx2.c
+++ b/net/netfilter/nft_set_pipapo_avx2.c
@@ -1134,6 +1134,7 @@ struct nft_pipapo_elem *pipapo_get_avx2(const struct nft_pipapo_match *m,
        struct nft_pipapo_scratch *scratch;
        const struct nft_pipapo_field *f;
        unsigned long *res, *fill, *map;
+       struct nft_pipapo_elem *e;
        bool map_index;
        int ret = 0;
        int i;
@@ -1207,14 +1208,11 @@ struct nft_pipapo_elem *pipapo_get_avx2(const struct nft_pipapo_match *m,
 next_match:
                if (ret < 0) {
                        scratch->map_index = map_index;
-                       kernel_fpu_end();
-                       __local_unlock_nested_bh(&scratch->bh_lock);
-                       return NULL;
+                       e = NULL;
+                       goto out;
                }
 
                if (last) {
-                       struct nft_pipapo_elem *e;
-
                        e = f->mt[ret].e;
                        if (unlikely(__nft_set_elem_expired(&e->ext, tstamp) ||
                                     !nft_set_elem_active(&e->ext, genmask))) {
@@ -1224,9 +1222,7 @@ next_match:
                        }
 
                        scratch->map_index = map_index;
-                       kernel_fpu_end();
-                       __local_unlock_nested_bh(&scratch->bh_lock);
-                       return e;
+                       goto out;
                }
 
                map_index = !map_index;
@@ -1234,9 +1230,12 @@ next_match:
                data += NFT_PIPAPO_GROUPS_PADDED_SIZE(f);
        }
 
+       e = NULL;
+out:
+       asm volatile("vzeroupper");
        kernel_fpu_end();
        __local_unlock_nested_bh(&scratch->bh_lock);
-       return NULL;
+       return e;
 }
 
 /**