diff options
| -rw-r--r-- | include/net/netlink.h | 13 | ||||
| -rw-r--r-- | lib/nlattr.c | 23 |
2 files changed, 28 insertions, 8 deletions
diff --git a/include/net/netlink.h b/include/net/netlink.h index 0c154f98e987..b318b0a9f6c3 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -180,6 +180,7 @@ enum { NLA_S32, NLA_S64, NLA_BITFIELD32, + NLA_REJECT, __NLA_TYPE_MAX, }; @@ -208,9 +209,19 @@ enum { * NLA_MSECS Leaving the length field zero will verify the * given type fits, using it verifies minimum length * just like "All other" - * NLA_BITFIELD32 A 32-bit bitmap/bitselector attribute + * NLA_BITFIELD32 Unused + * NLA_REJECT Unused * All other Minimum length of attribute payload * + * Meaning of `validation_data' field: + * NLA_BITFIELD32 This is a 32-bit bitmap/bitselector attribute and + * validation data must point to a u32 value of valid + * flags + * NLA_REJECT This attribute is always rejected and validation data + * may point to a string to report as the error instead + * of the generic one in extended ACK. + * All other Unused + * * Example: * static const struct nla_policy my_policy[ATTR_MAX+1] = { * [ATTR_FOO] = { .type = NLA_U16 }, diff --git a/lib/nlattr.c b/lib/nlattr.c index e335bcafa9e4..36d74b079151 100644 --- a/lib/nlattr.c +++ b/lib/nlattr.c @@ -69,7 +69,8 @@ static int validate_nla_bitfield32(const struct nlattr *nla, } static int validate_nla(const struct nlattr *nla, int maxtype, - const struct nla_policy *policy) + const struct nla_policy *policy, + const char **error_msg) { const struct nla_policy *pt; int minlen = 0, attrlen = nla_len(nla), type = nla_type(nla); @@ -87,6 +88,11 @@ static int validate_nla(const struct nlattr *nla, int maxtype, } switch (pt->type) { + case NLA_REJECT: + if (pt->validation_data && error_msg) + *error_msg = pt->validation_data; + return -EINVAL; + case NLA_FLAG: if (attrlen > 0) return -ERANGE; @@ -180,11 +186,10 @@ int nla_validate(const struct nlattr *head, int len, int maxtype, int rem; nla_for_each_attr(nla, head, len, rem) { - int err = validate_nla(nla, maxtype, policy); + int err = validate_nla(nla, maxtype, policy, NULL); if (err < 0) { - if (extack) - extack->bad_attr = nla; + NL_SET_BAD_ATTR(extack, nla); return err; } } @@ -250,11 +255,15 @@ int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head, 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); + err = validate_nla(nla, maxtype, policy, &msg); if (err < 0) { - NL_SET_ERR_MSG_ATTR(extack, nla, - "Attribute failed policy validation"); + NL_SET_BAD_ATTR(extack, nla); + if (extack) + extack->_msg = msg; goto errout; } } |