diff options
author | Johannes Berg <johannes.berg@intel.com> | 2018-09-26 11:15:32 +0200 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2018-09-28 10:24:39 -0700 |
commit | c29f1845b2b22974411278bad3a2ac0b7815dfb4 (patch) | |
tree | 068b778699737fdf5bc184913423daa334412c1a /lib | |
parent | 48fde90a78f8c67e2bec5061f9725fe363519feb (diff) | |
download | linux-stable-c29f1845b2b22974411278bad3a2ac0b7815dfb4.tar.gz linux-stable-c29f1845b2b22974411278bad3a2ac0b7815dfb4.tar.bz2 linux-stable-c29f1845b2b22974411278bad3a2ac0b7815dfb4.zip |
netlink: move extack setting into validate_nla()
This unifies the code between nla_parse() which sets the bad
attribute pointer and an error message, and nla_validate()
which only sets the bad attribute pointer.
It also cleans up the code for NLA_REJECT and paves the way
for nested policy validation, as it will allow us to easily
skip setting the "generic" message without any extra args
like the **error_msg now, just passing the extack through is
now enough.
While at it, remove the unnecessary label in nla_parse().
Suggested-by: David Ahern <dsahern@gmail.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'lib')
-rw-r--r-- | lib/nlattr.c | 68 |
1 files changed, 36 insertions, 32 deletions
diff --git a/lib/nlattr.c b/lib/nlattr.c index e2e5b38394d5..6e03d650bec4 100644 --- a/lib/nlattr.c +++ b/lib/nlattr.c @@ -69,10 +69,11 @@ 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 char **error_msg) + struct netlink_ext_ack *extack) { const struct nla_policy *pt; int minlen = 0, attrlen = nla_len(nla), type = nla_type(nla); + int err = -ERANGE; if (type <= 0 || type > maxtype) return 0; @@ -90,24 +91,31 @@ static int validate_nla(const struct nlattr *nla, int maxtype, switch (pt->type) { case NLA_EXACT_LEN: if (attrlen != pt->len) - return -ERANGE; + goto out_err; break; case NLA_REJECT: - if (pt->validation_data && error_msg) - *error_msg = pt->validation_data; - return -EINVAL; + if (extack && pt->validation_data) { + NL_SET_BAD_ATTR(extack, nla); + extack->_msg = pt->validation_data; + return -EINVAL; + } + err = -EINVAL; + goto out_err; case NLA_FLAG: if (attrlen > 0) - return -ERANGE; + goto out_err; break; case NLA_BITFIELD32: if (attrlen != sizeof(struct nla_bitfield32)) - return -ERANGE; + goto out_err; - return validate_nla_bitfield32(nla, pt->validation_data); + err = validate_nla_bitfield32(nla, pt->validation_data); + if (err) + goto out_err; + break; case NLA_NUL_STRING: if (pt->len) @@ -115,13 +123,15 @@ static int validate_nla(const struct nlattr *nla, int maxtype, else minlen = attrlen; - if (!minlen || memchr(nla_data(nla), '\0', minlen) == NULL) - return -EINVAL; + if (!minlen || memchr(nla_data(nla), '\0', minlen) == NULL) { + err = -EINVAL; + goto out_err; + } /* fall through */ case NLA_STRING: if (attrlen < 1) - return -ERANGE; + goto out_err; if (pt->len) { char *buf = nla_data(nla); @@ -130,13 +140,13 @@ static int validate_nla(const struct nlattr *nla, int maxtype, attrlen--; if (attrlen > pt->len) - return -ERANGE; + goto out_err; } break; case NLA_BINARY: if (pt->len && attrlen > pt->len) - return -ERANGE; + goto out_err; break; case NLA_NESTED: @@ -152,10 +162,13 @@ static int validate_nla(const struct nlattr *nla, int maxtype, minlen = nla_attr_minlen[pt->type]; if (attrlen < minlen) - return -ERANGE; + goto out_err; } return 0; +out_err: + NL_SET_ERR_MSG_ATTR(extack, nla, "Attribute failed policy validation"); + return err; } /** @@ -180,12 +193,10 @@ 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, NULL); + int err = validate_nla(nla, maxtype, policy, extack); - if (err < 0) { - NL_SET_BAD_ATTR(extack, nla); + if (err < 0) return err; - } } return 0; @@ -241,7 +252,7 @@ int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head, struct netlink_ext_ack *extack) { const struct nlattr *nla; - int rem, err; + int rem; memset(tb, 0, sizeof(struct nlattr *) * (maxtype + 1)); @@ -249,17 +260,12 @@ 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, &msg); - if (err < 0) { - NL_SET_BAD_ATTR(extack, nla); - if (extack) - extack->_msg = msg; - goto errout; - } + int err = validate_nla(nla, maxtype, policy, + extack); + + if (err < 0) + return err; } tb[type] = (struct nlattr *)nla; @@ -270,9 +276,7 @@ int nla_parse(struct nlattr **tb, int maxtype, const struct nlattr *head, 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); |