From: Johannes Berg <johannes.b...@intel.com> The parse function of course contains validate, but it's implemented a second time, sharing just the validation of a single attribute.
Introduce nla_validate_parse() that can be used for both parsing/validation and only validation, to share code. Signed-off-by: Johannes Berg <johannes.b...@intel.com> --- lib/nlattr.c | 76 +++++++++++++++++++++++++++++++----------------------------- 1 file changed, 39 insertions(+), 37 deletions(-) diff --git a/lib/nlattr.c b/lib/nlattr.c index efbd6c1aff29..46a6d79cf2d1 100644 --- a/lib/nlattr.c +++ b/lib/nlattr.c @@ -159,6 +159,37 @@ static int validate_nla(const struct nlattr *nla, int maxtype, return 0; } +static int nla_validate_parse(const struct nlattr *head, int len, int maxtype, + const struct nla_policy *policy, + struct netlink_ext_ack *extack, + struct nlattr **tb) +{ + const struct nlattr *nla; + int rem; + + nla_for_each_attr(nla, head, len, rem) { + static const char _msg[] = "Attribute failed policy validation"; + const char *msg = _msg; + u16 type = nla_type(nla); + + if (policy) { + int err = validate_nla(nla, maxtype, policy, &msg); + + if (err < 0) { + if (extack) + extack->_msg = msg; + NL_SET_BAD_ATTR(extack, nla); + return err; + } + } + + if (tb && type > 0 && type <= maxtype) + tb[type] = (struct nlattr *)nla; + } + + return rem; +} + /** * nla_validate - Validate a stream of attributes * @head: head of attribute stream @@ -177,21 +208,12 @@ int nla_validate(const struct nlattr *head, int len, int maxtype, const struct nla_policy *policy, struct netlink_ext_ack *extack) { - const struct nlattr *nla; int rem; - nla_for_each_attr(nla, head, len, rem) { - static const char _msg[] = "Attribute failed policy validation"; - const char *msg = _msg; - int err = validate_nla(nla, maxtype, policy, &msg); + rem = nla_validate_parse(head, len, maxtype, policy, extack, NULL); - if (err < 0) { - if (extack) - extack->_msg = msg; - NL_SET_BAD_ATTR(extack, nla); - return err; - } - } + if (rem < 0) + return rem; return 0; } @@ -245,39 +267,19 @@ int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head, int len, const struct nla_policy *policy, struct netlink_ext_ack *extack) { - const struct nlattr *nla; - int rem, err; + int rem; memset(tb, 0, sizeof(struct nlattr *) * (maxtype + 1)); - nla_for_each_attr(nla, head, len, rem) { - u16 type = nla_type(nla); - - if (type > 0 && type <= maxtype) { - static const char _msg[] = "Attribute failed policy validation"; - const char *msg = _msg; - - if (policy) { - err = validate_nla(nla, maxtype, policy, &msg); - if (err < 0) { - NL_SET_BAD_ATTR(extack, nla); - if (extack) - extack->_msg = msg; - goto errout; - } - } - - tb[type] = (struct nlattr *)nla; - } - } + rem = nla_validate_parse(head, len, maxtype, policy, extack, tb); + if (rem < 0) + return rem; if (unlikely(rem > 0)) pr_warn_ratelimited("netlink: %d bytes leftover after parsing attributes in process `%s'.\n", rem, current->comm); - err = 0; -errout: - return err; + return 0; } EXPORT_SYMBOL(nla_parse); -- 2.14.4