diff options
author | Johannes Berg <johannes.berg@intel.com> | 2020-10-02 10:46:04 +0300 |
---|---|---|
committer | David S. Miller <davem@davemloft.net> | 2020-10-02 23:07:42 +0300 |
commit | 949ca6b82e43b342dba153a9fd643fb1b5e9f034 (patch) | |
tree | 2c6e4b48a50f0cbed8cc9600fa40c4146e9b52c3 /net | |
parent | 360f89874635b08057757376b8cc4faa221862e2 (diff) |
netlink: fix policy dump leak
[ Upstream commit a95bc734e60449e7b073ff7ff70c35083b290ae9 ]
If userspace doesn't complete the policy dump, we leak the
allocated state. Fix this.
Fixes: d07dcf9aadd6 ("netlink: add infrastructure to expose policies to userspace")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net')
-rw-r--r-- | net/netlink/genetlink.c | 9 | ||||
-rw-r--r-- | net/netlink/policy.c | 24 |
2 files changed, 18 insertions, 15 deletions
diff --git a/net/netlink/genetlink.c b/net/netlink/genetlink.c index 3a718e327515..4a95e85cf907 100644 --- a/net/netlink/genetlink.c +++ b/net/netlink/genetlink.c @@ -1079,7 +1079,7 @@ static int ctrl_dumppolicy(struct sk_buff *skb, struct netlink_callback *cb) if (err) return err; - while (netlink_policy_dump_loop(&cb->args[1])) { + while (netlink_policy_dump_loop(cb->args[1])) { void *hdr; struct nlattr *nest; @@ -1113,6 +1113,12 @@ nla_put_failure: return skb->len; } +static int ctrl_dumppolicy_done(struct netlink_callback *cb) +{ + netlink_policy_dump_free(cb->args[1]); + return 0; +} + static const struct genl_ops genl_ctrl_ops[] = { { .cmd = CTRL_CMD_GETFAMILY, @@ -1123,6 +1129,7 @@ static const struct genl_ops genl_ctrl_ops[] = { { .cmd = CTRL_CMD_GETPOLICY, .dumpit = ctrl_dumppolicy, + .done = ctrl_dumppolicy_done, }, }; diff --git a/net/netlink/policy.c b/net/netlink/policy.c index 62f977fa645a..7a9792442578 100644 --- a/net/netlink/policy.c +++ b/net/netlink/policy.c @@ -84,7 +84,6 @@ int netlink_policy_dump_start(const struct nla_policy *policy, unsigned int policy_idx; int err; - /* also returns 0 if "*_state" is our ERR_PTR() end marker */ if (*_state) return 0; @@ -140,21 +139,11 @@ static bool netlink_policy_dump_finished(struct nl_policy_dump *state) !state->policies[state->policy_idx].policy; } -bool netlink_policy_dump_loop(unsigned long *_state) +bool netlink_policy_dump_loop(unsigned long _state) { - struct nl_policy_dump *state = (void *)*_state; - - if (IS_ERR(state)) - return false; - - if (netlink_policy_dump_finished(state)) { - kfree(state); - /* store end marker instead of freed state */ - *_state = (unsigned long)ERR_PTR(-ENOENT); - return false; - } + struct nl_policy_dump *state = (void *)_state; - return true; + return !netlink_policy_dump_finished(state); } int netlink_policy_dump_write(struct sk_buff *skb, unsigned long _state) @@ -316,3 +305,10 @@ nla_put_failure: nla_nest_cancel(skb, policy); return -ENOBUFS; } + +void netlink_policy_dump_free(unsigned long _state) +{ + struct nl_policy_dump *state = (void *)_state; + + kfree(state); +} |