From: Alin Nastac Date: Wed, 30 May 2018 13:19:36 +0000 (+0200) Subject: netfilter: ebtables: fix compat entry padding X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=9e8c8dabb78e886ace989729e763d28c76f5169e;p=linux.git netfilter: ebtables: fix compat entry padding On arm64, ebt_entry_{match,watcher,target} structs are 40 bytes long while on 32-bit arm these structs have a size of 36 bytes. COMPAT_XT_ALIGN() macro cannot be used here to determine the necessary padding for the CONFIG_COMPAT because it imposes an 8-byte boundary alignment, condition that is not found in 32-bit ebtables application. Signed-off-by: Alin Nastac Acked-by: Florian Westphal Signed-off-by: Pablo Neira Ayuso --- diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c index 6ba639f6c51d1..5f459c8b79376 100644 --- a/net/bridge/netfilter/ebtables.c +++ b/net/bridge/netfilter/ebtables.c @@ -1610,16 +1610,16 @@ struct compat_ebt_entry_mwt { compat_uptr_t ptr; } u; compat_uint_t match_size; - compat_uint_t data[0]; + compat_uint_t data[0] __attribute__ ((aligned (__alignof__(struct compat_ebt_replace)))); }; /* account for possible padding between match_size and ->data */ static int ebt_compat_entry_padsize(void) { - BUILD_BUG_ON(XT_ALIGN(sizeof(struct ebt_entry_match)) < - COMPAT_XT_ALIGN(sizeof(struct compat_ebt_entry_mwt))); - return (int) XT_ALIGN(sizeof(struct ebt_entry_match)) - - COMPAT_XT_ALIGN(sizeof(struct compat_ebt_entry_mwt)); + BUILD_BUG_ON(sizeof(struct ebt_entry_match) < + sizeof(struct compat_ebt_entry_mwt)); + return (int) sizeof(struct ebt_entry_match) - + sizeof(struct compat_ebt_entry_mwt); } static int ebt_compat_match_offset(const struct xt_match *match,