diff options
| -rw-r--r-- | include/net/netlink.h | 10 | ||||
| -rw-r--r-- | include/uapi/linux/netlink.h | 2 | ||||
| -rw-r--r-- | lib/nlattr.c | 36 | ||||
| -rw-r--r-- | net/netlink/policy.c | 8 |
4 files changed, 56 insertions, 0 deletions
diff --git a/include/net/netlink.h b/include/net/netlink.h index c5aa46f379bc..2b9e41075f19 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -200,6 +200,7 @@ enum nla_policy_validation { NLA_VALIDATE_RANGE_WARN_TOO_LONG, NLA_VALIDATE_MIN, NLA_VALIDATE_MAX, + NLA_VALIDATE_MASK, NLA_VALIDATE_RANGE_PTR, NLA_VALIDATE_FUNCTION, }; @@ -317,6 +318,7 @@ struct nla_policy { u16 len; union { const u32 bitfield32_valid; + const u32 mask; const char *reject_message; const struct nla_policy *nested_policy; struct netlink_range_validation *range; @@ -368,6 +370,8 @@ struct nla_policy { (tp == NLA_S8 || tp == NLA_S16 || tp == NLA_S32 || tp == NLA_S64) #define __NLA_ENSURE(condition) BUILD_BUG_ON_ZERO(!(condition)) +#define NLA_ENSURE_UINT_TYPE(tp) \ + (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp)) + tp) #define NLA_ENSURE_UINT_OR_BINARY_TYPE(tp) \ (__NLA_ENSURE(__NLA_IS_UINT_TYPE(tp) || \ tp == NLA_MSECS || \ @@ -416,6 +420,12 @@ struct nla_policy { .max = _max, \ } +#define NLA_POLICY_MASK(tp, _mask) { \ + .type = NLA_ENSURE_UINT_TYPE(tp), \ + .validation_type = NLA_VALIDATE_MASK, \ + .mask = _mask, \ +} + #define NLA_POLICY_VALIDATE_FN(tp, fn, ...) { \ .type = NLA_ENSURE_NO_VALIDATION_PTR(tp), \ .validation_type = NLA_VALIDATE_FUNCTION, \ diff --git a/include/uapi/linux/netlink.h b/include/uapi/linux/netlink.h index eac8a6a648ea..d02e472ba54c 100644 --- a/include/uapi/linux/netlink.h +++ b/include/uapi/linux/netlink.h @@ -331,6 +331,7 @@ enum netlink_attribute_type { * the index, if limited inside the nesting (U32) * @NL_POLICY_TYPE_ATTR_BITFIELD32_MASK: valid mask for the * bitfield32 type (U32) + * @NL_POLICY_TYPE_ATTR_MASK: mask of valid bits for unsigned integers (U64) * @NL_POLICY_TYPE_ATTR_PAD: pad attribute for 64-bit alignment */ enum netlink_policy_type_attr { @@ -346,6 +347,7 @@ enum netlink_policy_type_attr { NL_POLICY_TYPE_ATTR_POLICY_MAXTYPE, NL_POLICY_TYPE_ATTR_BITFIELD32_MASK, NL_POLICY_TYPE_ATTR_PAD, + NL_POLICY_TYPE_ATTR_MASK, /* keep last */ __NL_POLICY_TYPE_ATTR_MAX, diff --git a/lib/nlattr.c b/lib/nlattr.c index 80ff9fe83696..9c99f5daa4d2 100644 --- a/lib/nlattr.c +++ b/lib/nlattr.c @@ -323,6 +323,37 @@ static int nla_validate_int_range(const struct nla_policy *pt, } } +static int nla_validate_mask(const struct nla_policy *pt, + const struct nlattr *nla, + struct netlink_ext_ack *extack) +{ + u64 value; + + switch (pt->type) { + case NLA_U8: + value = nla_get_u8(nla); + break; + case NLA_U16: + value = nla_get_u16(nla); + break; + case NLA_U32: + value = nla_get_u32(nla); + break; + case NLA_U64: + value = nla_get_u64(nla); + break; + default: + return -EINVAL; + } + + if (value & ~(u64)pt->mask) { + NL_SET_ERR_MSG_ATTR(extack, nla, "reserved bit set"); + return -EINVAL; + } + + return 0; +} + static int validate_nla(const struct nlattr *nla, int maxtype, const struct nla_policy *policy, unsigned int validate, struct netlink_ext_ack *extack, unsigned int depth) @@ -503,6 +534,11 @@ static int validate_nla(const struct nlattr *nla, int maxtype, if (err) return err; break; + case NLA_VALIDATE_MASK: + err = nla_validate_mask(pt, nla, extack); + if (err) + return err; + break; case NLA_VALIDATE_FUNCTION: if (pt->validate) { err = pt->validate(nla, extack); diff --git a/net/netlink/policy.c b/net/netlink/policy.c index cf23c0151721..ee26d01328ee 100644 --- a/net/netlink/policy.c +++ b/net/netlink/policy.c @@ -263,6 +263,14 @@ send_attribute: else type = NL_ATTR_TYPE_U64; + if (pt->validation_type == NLA_VALIDATE_MASK) { + if (nla_put_u64_64bit(skb, NL_POLICY_TYPE_ATTR_MASK, + pt->mask, + NL_POLICY_TYPE_ATTR_PAD)) + goto nla_put_failure; + break; + } + nla_get_range_unsigned(pt, &range); if (nla_put_u64_64bit(skb, NL_POLICY_TYPE_ATTR_MIN_VALUE_U, |