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| author | Jakub Kicinski <kuba@kernel.org> | 2020-10-09 20:22:49 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2020-10-09 20:22:49 -0700 |
| commit | c77fb07fae36a02c382b729f856d45dade88a581 (patch) | |
| tree | e36d5d8e5795a8992618cc2f756c5bc38d977434 /include/linux | |
| parent | c4cc0b9c771a5199ef4e37f65e12dd25c56859d6 (diff) | |
| parent | 44f3625bc61653ea3bde9960298faf2f5518fda5 (diff) | |
| download | cachepc-linux-c77fb07fae36a02c382b729f856d45dade88a581.tar.gz cachepc-linux-c77fb07fae36a02c382b729f856d45dade88a581.zip | |
Merge branch 'netlink-export-policy-on-validation-failures'
Johannes Berg says:
====================
netlink: export policy on validation failures
Export the policy used for attribute validation when it fails,
so e.g. for an out-of-range attribute userspace immediately gets
the valid ranges back.
v2 incorporates the suggestion from Jakub to have a function to
estimate the size (netlink_policy_dump_attr_size_estimate()) and
check that it does the right thing on the *normal* policy dumps,
not (just) when calling it from the error scenario.
v3 only addresses a few minor style issues.
v4 fixes up a forgotten 'git add' ... sorry.
v5 is a resend, I messed up v4's cover letter subject (saying v3)
and apparently the second patch didn't go out at all.
Tested using nl80211/iw in a few scenarios, seems to work fine
and return the policy back, e.g.
kernel reports: integer out of range
policy: 04 00 0b 00 0c 00 04 00 01 00 00 00 00 00 00 00
^ padding
^ minimum allowed value
policy: 04 00 0b 00 0c 00 05 00 ff ff ff ff 00 00 00 00
^ padding
^ maximum allowed value
policy: 08 00 01 00 04 00 00 00
^ type 4 == U32
for an out-of-range case.
====================
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'include/linux')
| -rw-r--r-- | include/linux/netlink.h | 30 |
1 files changed, 20 insertions, 10 deletions
diff --git a/include/linux/netlink.h b/include/linux/netlink.h index e3e49f0e5c13..666cd0390699 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -68,12 +68,14 @@ netlink_kernel_create(struct net *net, int unit, struct netlink_kernel_cfg *cfg) * @_msg: message string to report - don't access directly, use * %NL_SET_ERR_MSG * @bad_attr: attribute with error + * @policy: policy for a bad attribute * @cookie: cookie data to return to userspace (for success) * @cookie_len: actual cookie data length */ struct netlink_ext_ack { const char *_msg; const struct nlattr *bad_attr; + const struct nla_policy *policy; u8 cookie[NETLINK_MAX_COOKIE_LEN]; u8 cookie_len; }; @@ -95,21 +97,29 @@ struct netlink_ext_ack { #define NL_SET_ERR_MSG_MOD(extack, msg) \ NL_SET_ERR_MSG((extack), KBUILD_MODNAME ": " msg) -#define NL_SET_BAD_ATTR(extack, attr) do { \ - if ((extack)) \ +#define NL_SET_BAD_ATTR_POLICY(extack, attr, pol) do { \ + if ((extack)) { \ (extack)->bad_attr = (attr); \ + (extack)->policy = (pol); \ + } \ } while (0) -#define NL_SET_ERR_MSG_ATTR(extack, attr, msg) do { \ - static const char __msg[] = msg; \ - struct netlink_ext_ack *__extack = (extack); \ - \ - if (__extack) { \ - __extack->_msg = __msg; \ - __extack->bad_attr = (attr); \ - } \ +#define NL_SET_BAD_ATTR(extack, attr) NL_SET_BAD_ATTR_POLICY(extack, attr, NULL) + +#define NL_SET_ERR_MSG_ATTR_POL(extack, attr, pol, msg) do { \ + static const char __msg[] = msg; \ + struct netlink_ext_ack *__extack = (extack); \ + \ + if (__extack) { \ + __extack->_msg = __msg; \ + __extack->bad_attr = (attr); \ + __extack->policy = (pol); \ + } \ } while (0) +#define NL_SET_ERR_MSG_ATTR(extack, attr, msg) \ + NL_SET_ERR_MSG_ATTR_POL(extack, attr, NULL, msg) + static inline void nl_set_extack_cookie_u64(struct netlink_ext_ack *extack, u64 cookie) { |