iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

netfilter: nft_compat: explicitly reject ERROR and standard target

Browse Source 
iptables-nft never requests these, but make this explicitly illegal.
If it were quested, kernel could oops as ->eval is NULL, furthermore,
the builtin targets have no owning module so its possible to rmmod
eb/ip/ip6_tables module even if they would be loaded.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
This commit is contained in:
Florian Westphal 2018-07-06 20:06:05 +02:00 committed by Pablo Neira Ayuso
parent e240cd0df4
commit 21d5e07819
1 changed files with 13 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

13
net/netfilter/nft_compat.c
View File

@ -832,10 +832,18 @@ nft_target_select_ops(const struct nft_ctx *ctx,
rev = ntohl(nla_get_be32(tb[NFTA_TARGET_REV]));
family = ctx->family;
if (strcmp(tg_name, XT_ERROR_TARGET) == 0 ||
strcmp(tg_name, XT_STANDARD_TARGET) == 0 ||
strcmp(tg_name, "standard") == 0)
return ERR_PTR(-EINVAL);
/* Re-use the existing target if it's already loaded. */
list_for_each_entry(nft_target, &nft_target_list, head) {
struct xt_target *target = nft_target->ops.data;
if (!target->target)
continue;
if (nft_target_cmp(target, tg_name, rev, family))
return &nft_target->ops;
}
@ -844,6 +852,11 @@ nft_target_select_ops(const struct nft_ctx *ctx,
if (IS_ERR(target))
return ERR_PTR(-ENOENT);
if (!target->target) {
err = -EINVAL;
goto err;
}
if (target->targetsize > nla_len(tb[NFTA_TARGET_INFO])) {
err = -EINVAL;
goto err;