diff options
Diffstat (limited to 'net/netfilter/x_tables.c')
-rw-r--r-- | net/netfilter/x_tables.c | 104 |
1 files changed, 64 insertions, 40 deletions
diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c index 2f685ee1f9c8..4aa01c90e9d1 100644 --- a/net/netfilter/x_tables.c +++ b/net/netfilter/x_tables.c @@ -423,6 +423,36 @@ textify_hooks(char *buf, size_t size, unsigned int mask, uint8_t nfproto) return buf; } +/** + * xt_check_proc_name - check that name is suitable for /proc file creation + * + * @name: file name candidate + * @size: length of buffer + * + * some x_tables modules wish to create a file in /proc. + * This function makes sure that the name is suitable for this + * purpose, it checks that name is NUL terminated and isn't a 'special' + * name, like "..". + * + * returns negative number on error or 0 if name is useable. + */ +int xt_check_proc_name(const char *name, unsigned int size) +{ + if (name[0] == '\0') + return -EINVAL; + + if (strnlen(name, size) == size) + return -ENAMETOOLONG; + + if (strcmp(name, ".") == 0 || + strcmp(name, "..") == 0 || + strchr(name, '/')) + return -EINVAL; + + return 0; +} +EXPORT_SYMBOL(xt_check_proc_name); + int xt_check_match(struct xt_mtchk_param *par, unsigned int size, u_int8_t proto, bool inv_proto) { @@ -434,36 +464,35 @@ int xt_check_match(struct xt_mtchk_param *par, * ebt_among is exempt from centralized matchsize checking * because it uses a dynamic-size data set. */ - pr_err("%s_tables: %s.%u match: invalid size " - "%u (kernel) != (user) %u\n", - xt_prefix[par->family], par->match->name, - par->match->revision, - XT_ALIGN(par->match->matchsize), size); + pr_err_ratelimited("%s_tables: %s.%u match: invalid size %u (kernel) != (user) %u\n", + xt_prefix[par->family], par->match->name, + par->match->revision, + XT_ALIGN(par->match->matchsize), size); return -EINVAL; } if (par->match->table != NULL && strcmp(par->match->table, par->table) != 0) { - pr_err("%s_tables: %s match: only valid in %s table, not %s\n", - xt_prefix[par->family], par->match->name, - par->match->table, par->table); + pr_info_ratelimited("%s_tables: %s match: only valid in %s table, not %s\n", + xt_prefix[par->family], par->match->name, + par->match->table, par->table); return -EINVAL; } if (par->match->hooks && (par->hook_mask & ~par->match->hooks) != 0) { char used[64], allow[64]; - pr_err("%s_tables: %s match: used from hooks %s, but only " - "valid from %s\n", - xt_prefix[par->family], par->match->name, - textify_hooks(used, sizeof(used), par->hook_mask, - par->family), - textify_hooks(allow, sizeof(allow), par->match->hooks, - par->family)); + pr_info_ratelimited("%s_tables: %s match: used from hooks %s, but only valid from %s\n", + xt_prefix[par->family], par->match->name, + textify_hooks(used, sizeof(used), + par->hook_mask, par->family), + textify_hooks(allow, sizeof(allow), + par->match->hooks, + par->family)); return -EINVAL; } if (par->match->proto && (par->match->proto != proto || inv_proto)) { - pr_err("%s_tables: %s match: only valid for protocol %u\n", - xt_prefix[par->family], par->match->name, - par->match->proto); + pr_info_ratelimited("%s_tables: %s match: only valid for protocol %u\n", + xt_prefix[par->family], par->match->name, + par->match->proto); return -EINVAL; } if (par->match->checkentry != NULL) { @@ -814,36 +843,35 @@ int xt_check_target(struct xt_tgchk_param *par, int ret; if (XT_ALIGN(par->target->targetsize) != size) { - pr_err("%s_tables: %s.%u target: invalid size " - "%u (kernel) != (user) %u\n", - xt_prefix[par->family], par->target->name, - par->target->revision, - XT_ALIGN(par->target->targetsize), size); + pr_err_ratelimited("%s_tables: %s.%u target: invalid size %u (kernel) != (user) %u\n", + xt_prefix[par->family], par->target->name, + par->target->revision, + XT_ALIGN(par->target->targetsize), size); return -EINVAL; } if (par->target->table != NULL && strcmp(par->target->table, par->table) != 0) { - pr_err("%s_tables: %s target: only valid in %s table, not %s\n", - xt_prefix[par->family], par->target->name, - par->target->table, par->table); + pr_info_ratelimited("%s_tables: %s target: only valid in %s table, not %s\n", + xt_prefix[par->family], par->target->name, + par->target->table, par->table); return -EINVAL; } if (par->target->hooks && (par->hook_mask & ~par->target->hooks) != 0) { char used[64], allow[64]; - pr_err("%s_tables: %s target: used from hooks %s, but only " - "usable from %s\n", - xt_prefix[par->family], par->target->name, - textify_hooks(used, sizeof(used), par->hook_mask, - par->family), - textify_hooks(allow, sizeof(allow), par->target->hooks, - par->family)); + pr_info_ratelimited("%s_tables: %s target: used from hooks %s, but only usable from %s\n", + xt_prefix[par->family], par->target->name, + textify_hooks(used, sizeof(used), + par->hook_mask, par->family), + textify_hooks(allow, sizeof(allow), + par->target->hooks, + par->family)); return -EINVAL; } if (par->target->proto && (par->target->proto != proto || inv_proto)) { - pr_err("%s_tables: %s target: only valid for protocol %u\n", - xt_prefix[par->family], par->target->name, - par->target->proto); + pr_info_ratelimited("%s_tables: %s target: only valid for protocol %u\n", + xt_prefix[par->family], par->target->name, + par->target->proto); return -EINVAL; } if (par->target->checkentry != NULL) { @@ -1004,10 +1032,6 @@ struct xt_table_info *xt_alloc_table_info(unsigned int size) if (sz < sizeof(*info)) return NULL; - /* Pedantry: prevent them from hitting BUG() in vmalloc.c --RR */ - if ((size >> PAGE_SHIFT) + 2 > totalram_pages) - return NULL; - /* __GFP_NORETRY is not fully supported by kvmalloc but it should * work reasonably well if sz is too large and bail out rather * than shoot all processes down before realizing there is nothing |