netfilter: nf_tables: handle more than 8 * PAGE_SIZE set name allocations

We currently have a limit of 8 * PAGE_SIZE anonymous sets. Lift that limit
by continuing the scan if the entire page is exhausted.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/net/netfilter/nf_tables_api.c b/net/netfilter/nf_tables_api.c
index 60feca9aa70a0c0f5e3a8115287028c6bdc5a035..1c5e6335b2e3cae4774c0ac98205f1e28dece02e 100644 (file)
--- a/net/netfilter/nf_tables_api.c
+++ b/net/netfilter/nf_tables_api.c
@@ -2049,7 +2049,7 @@ static int nf_tables_set_alloc_name(struct nft_ctx *ctx, struct nft_set *set,
        const struct nft_set *i;
        const char *p;
        unsigned long *inuse;
-       unsigned int n = 0;
+       unsigned int n = 0, min = 0;
 
        p = strnchr(name, IFNAMSIZ, '%');
        if (p != NULL) {
@@ -2059,23 +2059,28 @@ static int nf_tables_set_alloc_name(struct nft_ctx *ctx, struct nft_set *set,
                inuse = (unsigned long *)get_zeroed_page(GFP_KERNEL);
                if (inuse == NULL)
                        return -ENOMEM;
-
+cont:
                list_for_each_entry(i, &ctx->table->sets, list) {
                        int tmp;
 
                        if (!sscanf(i->name, name, &tmp))
                                continue;
-                       if (tmp < 0 || tmp >= BITS_PER_BYTE * PAGE_SIZE)
+                       if (tmp < min || tmp >= min + BITS_PER_BYTE * PAGE_SIZE)
                                continue;
 
-                       set_bit(tmp, inuse);
+                       set_bit(tmp - min, inuse);
                }
 
                n = find_first_zero_bit(inuse, BITS_PER_BYTE * PAGE_SIZE);
+               if (n >= BITS_PER_BYTE * PAGE_SIZE) {
+                       min += BITS_PER_BYTE * PAGE_SIZE;
+                       memset(inuse, 0, PAGE_SIZE);
+                       goto cont;
+               }
                free_page((unsigned long)inuse);
        }
 
-       snprintf(set->name, sizeof(set->name), name, n);
+       snprintf(set->name, sizeof(set->name), name, min + n);
        list_for_each_entry(i, &ctx->table->sets, list) {
                if (!strcmp(set->name, i->name))
                        return -ENFILE;