diff options
| author | Xin Long <lucien.xin@gmail.com> | 2017-08-18 11:01:36 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2017-08-30 10:21:42 +0200 |
| commit | 3e00bf91fefced104ba91721674efe4502cb416a (patch) | |
| tree | b5c65a0b185a5e5d23b29fcb9064294f7eadfc8c /net/sched | |
| parent | f3f5bf2755c75d43930aab28f1affd0602e6fd27 (diff) | |
net: sched: fix NULL pointer dereference when action calls some targets
[ Upstream commit 4f8a881acc9d1adaf1e552349a0b1df28933a04c ]
As we know in some target's checkentry it may dereference par.entryinfo
to check entry stuff inside. But when sched action calls xt_check_target,
par.entryinfo is set with NULL. It would cause kernel panic when calling
some targets.
It can be reproduce with:
# tc qd add dev eth1 ingress handle ffff:
# tc filter add dev eth1 parent ffff: u32 match u32 0 0 action xt \
-j ECN --ecn-tcp-remove
It could also crash kernel when using target CLUSTERIP or TPROXY.
By now there's no proper value for par.entryinfo in ipt_init_target,
but it can not be set with NULL. This patch is to void all these
panics by setting it with an ipt_entry obj with all members = 0.
Note that this issue has been there since the very beginning.
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'net/sched')
| -rw-r--r-- | net/sched/act_ipt.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/net/sched/act_ipt.c b/net/sched/act_ipt.c index a1aec0a6c789..50030519a89b 100644 --- a/net/sched/act_ipt.c +++ b/net/sched/act_ipt.c @@ -41,6 +41,7 @@ static int ipt_init_target(struct xt_entry_target *t, char *table, { struct xt_tgchk_param par; struct xt_target *target; + struct ipt_entry e = {}; int ret = 0; target = xt_request_find_target(AF_INET, t->u.user.name, @@ -51,6 +52,7 @@ static int ipt_init_target(struct xt_entry_target *t, char *table, t->u.kernel.target = target; memset(&par, 0, sizeof(par)); par.table = table; + par.entryinfo = &e; par.target = target; par.targinfo = t->data; par.hook_mask = hook; |