netfilter: nft_set_pipapo: prefer kvmalloc for scratch maps

The scratchmap size depends on the number of elements in the set.
For huge sets, each scratch map can easily require very large
allocations, e.g. for 100k entries each scratch map will require
close to 64kbyte of memory.

Signed-off-by: Florian Westphal <fw@strlen.de>
Reviewed-by: Stefano Brivio <sbrivio@redhat.com>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

Author: Florian Westphal

net/netfilter/nft_set_pipapo.c

@@ -1152,7 +1152,7 @@ static void pipapo_free_scratch(const struct nft_pipapo_match *m, unsigned int c
 
 	mem = s;
 	mem -= s->align_off;
-	kfree(mem);
+	kvfree(mem);
 }
 
 /**
@@ -1173,10 +1173,9 @@ static int pipapo_realloc_scratch(struct nft_pipapo_match *clone,
 		void *scratch_aligned;
 		u32 align_off;
 #endif
-		scratch = kzalloc_node(struct_size(scratch, map,
-						   bsize_max * 2) +
-				       NFT_PIPAPO_ALIGN_HEADROOM,
-				       GFP_KERNEL_ACCOUNT, cpu_to_node(i));
+		scratch = kvzalloc_node(struct_size(scratch, map, bsize_max * 2) +
+					NFT_PIPAPO_ALIGN_HEADROOM,
+					GFP_KERNEL_ACCOUNT, cpu_to_node(i));
 		if (!scratch) {
 			/* On failure, there's no need to undo previous
 			 * allocations: this means that some scratch maps have