From: Juliana Rodrigueiro juliana.rodrigueiro@intra2net.com
[ Upstream commit 89a26cd4b501e9511d3cd3d22327fc76a75a38b3 ]
When running a 64-bit kernel with a 32-bit iptables binary, the size of the xt_nfacct_match_info struct diverges.
kernel: sizeof(struct xt_nfacct_match_info) : 40 iptables: sizeof(struct xt_nfacct_match_info)) : 36
Trying to append nfacct related rules results in an unhelpful message. Although it is suggested to look for more information in dmesg, nothing can be found there.
# iptables -A <chain> -m nfacct --nfacct-name <acct-object> iptables: Invalid argument. Run `dmesg' for more information.
This patch fixes the memory misalignment by enforcing 8-byte alignment within the struct's first revision. This solution is often used in many other uapi netfilter headers.
Signed-off-by: Juliana Rodrigueiro juliana.rodrigueiro@intra2net.com Acked-by: Florian Westphal fw@strlen.de Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Sasha Levin sashal@kernel.org --- include/uapi/linux/netfilter/xt_nfacct.h | 5 ++++ net/netfilter/xt_nfacct.c | 36 ++++++++++++++++-------- 2 files changed, 30 insertions(+), 11 deletions(-)
diff --git a/include/uapi/linux/netfilter/xt_nfacct.h b/include/uapi/linux/netfilter/xt_nfacct.h index 5c8a4d760ee34..b5123ab8d54a8 100644 --- a/include/uapi/linux/netfilter/xt_nfacct.h +++ b/include/uapi/linux/netfilter/xt_nfacct.h @@ -11,4 +11,9 @@ struct xt_nfacct_match_info { struct nf_acct *nfacct; };
+struct xt_nfacct_match_info_v1 { + char name[NFACCT_NAME_MAX]; + struct nf_acct *nfacct __attribute__((aligned(8))); +}; + #endif /* _XT_NFACCT_MATCH_H */ diff --git a/net/netfilter/xt_nfacct.c b/net/netfilter/xt_nfacct.c index 6f92d25590a85..ea447b437f122 100644 --- a/net/netfilter/xt_nfacct.c +++ b/net/netfilter/xt_nfacct.c @@ -55,25 +55,39 @@ nfacct_mt_destroy(const struct xt_mtdtor_param *par) nfnl_acct_put(info->nfacct); }
-static struct xt_match nfacct_mt_reg __read_mostly = { - .name = "nfacct", - .family = NFPROTO_UNSPEC, - .checkentry = nfacct_mt_checkentry, - .match = nfacct_mt, - .destroy = nfacct_mt_destroy, - .matchsize = sizeof(struct xt_nfacct_match_info), - .usersize = offsetof(struct xt_nfacct_match_info, nfacct), - .me = THIS_MODULE, +static struct xt_match nfacct_mt_reg[] __read_mostly = { + { + .name = "nfacct", + .revision = 0, + .family = NFPROTO_UNSPEC, + .checkentry = nfacct_mt_checkentry, + .match = nfacct_mt, + .destroy = nfacct_mt_destroy, + .matchsize = sizeof(struct xt_nfacct_match_info), + .usersize = offsetof(struct xt_nfacct_match_info, nfacct), + .me = THIS_MODULE, + }, + { + .name = "nfacct", + .revision = 1, + .family = NFPROTO_UNSPEC, + .checkentry = nfacct_mt_checkentry, + .match = nfacct_mt, + .destroy = nfacct_mt_destroy, + .matchsize = sizeof(struct xt_nfacct_match_info_v1), + .usersize = offsetof(struct xt_nfacct_match_info_v1, nfacct), + .me = THIS_MODULE, + }, };
static int __init nfacct_mt_init(void) { - return xt_register_match(&nfacct_mt_reg); + return xt_register_matches(nfacct_mt_reg, ARRAY_SIZE(nfacct_mt_reg)); }
static void __exit nfacct_mt_exit(void) { - xt_unregister_match(&nfacct_mt_reg); + xt_unregister_matches(nfacct_mt_reg, ARRAY_SIZE(nfacct_mt_reg)); }
module_init(nfacct_mt_init);