diff options
author | Johannes Berg <johannes.berg@intel.com> | 2020-04-30 22:13:05 +0200 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2020-05-01 02:51:41 +0200 |
commit | 47a1494b8208461094923400c396ce4b8163c064 (patch) | |
tree | 922bbadbfa571fae66f3c3503d7e2331c403c632 /include/net/netlink.h | |
parent | Merge branch 'net-dsa-b53-ARL-improvements' (diff) | |
download | linux-47a1494b8208461094923400c396ce4b8163c064.tar.xz linux-47a1494b8208461094923400c396ce4b8163c064.zip |
netlink: remove type-unsafe validation_data pointer
In the netlink policy, we currently have a void *validation_data
that's pointing to different things:
* a u32 value for bitfield32,
* the netlink policy for nested/nested array
* the string for NLA_REJECT
Remove the pointer and place appropriate type-safe items in the
union instead.
While at it, completely dissolve the pointer for the bitfield32
case and just put the value there directly.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net/netlink.h')
-rw-r--r-- | include/net/netlink.h | 60 |
1 files changed, 32 insertions, 28 deletions
diff --git a/include/net/netlink.h b/include/net/netlink.h index 67c57d6942e3..671b29d170a8 100644 --- a/include/net/netlink.h +++ b/include/net/netlink.h @@ -217,7 +217,7 @@ enum nla_policy_validation { * NLA_NESTED, * NLA_NESTED_ARRAY Length verification is done by checking len of * nested header (or empty); len field is used if - * validation_data is also used, for the max attr + * nested_policy is also used, for the max attr * number in the nested policy. * NLA_U8, NLA_U16, * NLA_U32, NLA_U64, @@ -235,27 +235,25 @@ enum nla_policy_validation { * NLA_MIN_LEN Minimum length of attribute payload * All other Minimum length of attribute payload * - * Meaning of `validation_data' field: + * Meaning of validation union: * 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 + * `bitfield32_valid' is the u32 value of valid flags + * NLA_REJECT This attribute is always rejected and `reject_message' * may point to a string to report as the error instead * of the generic one in extended ACK. - * NLA_NESTED Points to a nested policy to validate, must also set - * `len' to the max attribute number. + * NLA_NESTED `nested_policy' to a nested policy to validate, must + * also set `len' to the max attribute number. Use the + * provided NLA_POLICY_NESTED() macro. * Note that nla_parse() will validate, but of course not * parse, the nested sub-policies. - * NLA_NESTED_ARRAY Points to a nested policy to validate, must also set - * `len' to the max attribute number. The difference to - * NLA_NESTED is the structure - NLA_NESTED has the - * nested attributes directly inside, while an array has - * the nested attributes at another level down and the - * attributes directly in the nesting don't matter. - * All other Unused - but note that it's a union - * - * Meaning of `min' and `max' fields, use via NLA_POLICY_MIN, NLA_POLICY_MAX - * and NLA_POLICY_RANGE: + * NLA_NESTED_ARRAY `nested_policy' points to a nested policy to validate, + * must also set `len' to the max attribute number. Use + * the provided NLA_POLICY_NESTED_ARRAY() macro. + * The difference to NLA_NESTED is the structure: + * NLA_NESTED has the nested attributes directly inside + * while an array has the nested attributes at another + * level down and the attribute types directly in the + * nesting don't matter. * NLA_U8, * NLA_U16, * NLA_U32, @@ -263,29 +261,31 @@ enum nla_policy_validation { * NLA_S8, * NLA_S16, * NLA_S32, - * NLA_S64 These are used depending on the validation_type - * field, if that is min/max/range then the minimum, - * maximum and both are used (respectively) to check + * NLA_S64 The `min' and `max' fields are used depending on the + * validation_type field, if that is min/max/range then + * the min, max or both are used (respectively) to check * the value of the integer attribute. * Note that in the interest of code simplicity and * struct size both limits are s16, so you cannot * enforce a range that doesn't fall within the range * of s16 - do that as usual in the code instead. + * Use the NLA_POLICY_MIN(), NLA_POLICY_MAX() and + * NLA_POLICY_RANGE() macros. * All other Unused - but note that it's a union * * Meaning of `validate' field, use via NLA_POLICY_VALIDATE_FN: - * NLA_BINARY Validation function called for the attribute, - * not compatible with use of the validation_data - * as in NLA_BITFIELD32, NLA_REJECT, NLA_NESTED and - * NLA_NESTED_ARRAY. + * NLA_BINARY Validation function called for the attribute. * All other Unused - but note that it's a union * * Example: + * + * static const u32 myvalidflags = 0xff231023; + * * static const struct nla_policy my_policy[ATTR_MAX+1] = { * [ATTR_FOO] = { .type = NLA_U16 }, * [ATTR_BAR] = { .type = NLA_STRING, .len = BARSIZ }, * [ATTR_BAZ] = { .type = NLA_EXACT_LEN, .len = sizeof(struct mystruct) }, - * [ATTR_GOO] = { .type = NLA_BITFIELD32, .validation_data = &myvalidflags }, + * [ATTR_GOO] = NLA_POLICY_BITFIELD32(myvalidflags), * }; */ struct nla_policy { @@ -293,7 +293,9 @@ struct nla_policy { u8 validation_type; u16 len; union { - const void *validation_data; + const u32 bitfield32_valid; + const char *reject_message; + const struct nla_policy *nested_policy; struct { s16 min, max; }; @@ -329,13 +331,15 @@ struct nla_policy { #define NLA_POLICY_ETH_ADDR_COMPAT NLA_POLICY_EXACT_LEN_WARN(ETH_ALEN) #define _NLA_POLICY_NESTED(maxattr, policy) \ - { .type = NLA_NESTED, .validation_data = policy, .len = maxattr } + { .type = NLA_NESTED, .nested_policy = policy, .len = maxattr } #define _NLA_POLICY_NESTED_ARRAY(maxattr, policy) \ - { .type = NLA_NESTED_ARRAY, .validation_data = policy, .len = maxattr } + { .type = NLA_NESTED_ARRAY, .nested_policy = policy, .len = maxattr } #define NLA_POLICY_NESTED(policy) \ _NLA_POLICY_NESTED(ARRAY_SIZE(policy) - 1, policy) #define NLA_POLICY_NESTED_ARRAY(policy) \ _NLA_POLICY_NESTED_ARRAY(ARRAY_SIZE(policy) - 1, policy) +#define NLA_POLICY_BITFIELD32(valid) \ + { .type = NLA_BITFIELD32, .bitfield32_valid = valid } #define __NLA_ENSURE(condition) BUILD_BUG_ON_ZERO(!(condition)) #define NLA_ENSURE_INT_TYPE(tp) \ |