diff options
| -rw-r--r-- | lib/nlattr.c | 22 |
1 files changed, 16 insertions, 6 deletions
diff --git a/lib/nlattr.c b/lib/nlattr.c index 8bf78b4b78f0..dfa55c873c13 100644 --- a/lib/nlattr.c +++ b/lib/nlattr.c @@ -15,7 +15,11 @@ #include <linux/types.h> #include <net/netlink.h> -/* for these data types attribute length must be exactly given size */ +/* For these data types, attribute length should be exactly the given + * size. However, to maintain compatibility with broken commands, if the + * attribute length does not match the expected size a warning is emitted + * to the user that the command is sending invalid data and needs to be fixed. + */ static const u8 nla_attr_len[NLA_TYPE_MAX+1] = { [NLA_U8] = sizeof(u8), [NLA_U16] = sizeof(u16), @@ -28,8 +32,16 @@ static const u8 nla_attr_len[NLA_TYPE_MAX+1] = { }; static const u8 nla_attr_minlen[NLA_TYPE_MAX+1] = { + [NLA_U8] = sizeof(u8), + [NLA_U16] = sizeof(u16), + [NLA_U32] = sizeof(u32), + [NLA_U64] = sizeof(u64), [NLA_MSECS] = sizeof(u64), [NLA_NESTED] = NLA_HDRLEN, + [NLA_S8] = sizeof(s8), + [NLA_S16] = sizeof(s16), + [NLA_S32] = sizeof(s32), + [NLA_S64] = sizeof(s64), }; static int validate_nla_bitfield32(const struct nlattr *nla, @@ -69,11 +81,9 @@ static int validate_nla(const struct nlattr *nla, int maxtype, BUG_ON(pt->type > NLA_TYPE_MAX); - /* for data types NLA_U* and NLA_S* require exact length */ - if (nla_attr_len[pt->type]) { - if (attrlen != nla_attr_len[pt->type]) - return -ERANGE; - return 0; + if (nla_attr_len[pt->type] && attrlen != nla_attr_len[pt->type]) { + pr_warn_ratelimited("netlink: '%s': attribute type %d has an invalid length.\n", + current->comm, type); } switch (pt->type) { |