From 4b2cbd42bef5a22bb681acd607a7c3fbca1eeb3c Mon Sep 17 00:00:00 2001 From: Jan Engelhardt Date: Tue, 27 Apr 2010 15:34:34 +0200 Subject: [PATCH] netfilter: x_tables: rectify XT_FUNCTION_MAXNAMELEN usage There has been quite a confusion in userspace about XT_FUNCTION_MAXNAMELEN; because struct xt_entry_match used MAX-1, userspace would have to do an awkward MAX-2 for maximum length checking (due to '\0'). This patch adds a new define that matches the definition of XT_TABLE_MAXNAMELEN - being the size of the actual struct member, not one off. Signed-off-by: Jan Engelhardt Signed-off-by: Patrick McHardy --- include/linux/netfilter/x_tables.h | 14 ++++++-------- 1 file changed, 6 insertions(+), 8 deletions(-) diff --git a/include/linux/netfilter/x_tables.h b/include/linux/netfilter/x_tables.h index 50c867256ca3..eeb4884c30be 100644 --- a/include/linux/netfilter/x_tables.h +++ b/include/linux/netfilter/x_tables.h @@ -4,6 +4,7 @@ #include #define XT_FUNCTION_MAXNAMELEN 30 +#define XT_EXTENSION_MAXNAMELEN 29 #define XT_TABLE_MAXNAMELEN 32 struct xt_entry_match { @@ -12,8 +13,7 @@ struct xt_entry_match { __u16 match_size; /* Used by userspace */ - char name[XT_FUNCTION_MAXNAMELEN-1]; - + char name[XT_EXTENSION_MAXNAMELEN]; __u8 revision; } user; struct { @@ -36,8 +36,7 @@ struct xt_entry_target { __u16 target_size; /* Used by userspace */ - char name[XT_FUNCTION_MAXNAMELEN-1]; - + char name[XT_EXTENSION_MAXNAMELEN]; __u8 revision; } user; struct { @@ -70,8 +69,7 @@ struct xt_standard_target { /* The argument to IPT_SO_GET_REVISION_*. Returns highest revision * kernel supports, if >= revision. */ struct xt_get_revision { - char name[XT_FUNCTION_MAXNAMELEN-1]; - + char name[XT_EXTENSION_MAXNAMELEN]; __u8 revision; }; @@ -291,7 +289,7 @@ struct xt_tgdtor_param { struct xt_match { struct list_head list; - const char name[XT_FUNCTION_MAXNAMELEN-1]; + const char name[XT_EXTENSION_MAXNAMELEN]; u_int8_t revision; /* Return true or false: return FALSE and set *hotdrop = 1 to @@ -330,7 +328,7 @@ struct xt_match { struct xt_target { struct list_head list; - const char name[XT_FUNCTION_MAXNAMELEN-1]; + const char name[XT_EXTENSION_MAXNAMELEN]; u_int8_t revision; /* Returns verdict. Argument order changed since 2.6.9, as this -- 2.39.5