diff options
author | Jason Baron <jbaron@akamai.com> | 2020-02-17 15:38:09 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-03-11 07:53:05 +0100 |
commit | 259384b9b2c27b63ed94851932b4c5bac7f9046c (patch) | |
tree | b77043b9ad75d64d3a5e298e32686d4242128856 | |
parent | 35ce64ab81e9323af94f425f82e4c9f07a0fd6e1 (diff) |
net: sched: correct flower port blocking
[ Upstream commit 8a9093c79863b58cc2f9874d7ae788f0d622a596 ]
tc flower rules that are based on src or dst port blocking are sometimes
ineffective due to uninitialized stack data. __skb_flow_dissect() extracts
ports from the skb for tc flower to match against. However, the port
dissection is not done when when the FLOW_DIS_IS_FRAGMENT bit is set in
key_control->flags. All callers of __skb_flow_dissect(), zero-out the
key_control field except for fl_classify() as used by the flower
classifier. Thus, the FLOW_DIS_IS_FRAGMENT may be set on entry to
__skb_flow_dissect(), since key_control is allocated on the stack
and may not be initialized.
Since key_basic and key_control are present for all flow keys, let's
make sure they are initialized.
Fixes: 62230715fd24 ("flow_dissector: do not dissect l4 ports for fragments")
Co-developed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Jason Baron <jbaron@akamai.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | include/net/flow_dissector.h | 9 | ||||
-rw-r--r-- | net/sched/cls_flower.c | 1 |
2 files changed, 10 insertions, 0 deletions
diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h index 1505cf7a4aaf..7a85a4ef6868 100644 --- a/include/net/flow_dissector.h +++ b/include/net/flow_dissector.h @@ -4,6 +4,7 @@ #include <linux/types.h> #include <linux/in6.h> #include <linux/siphash.h> +#include <linux/string.h> #include <uapi/linux/if_ether.h> /** @@ -204,4 +205,12 @@ static inline void *skb_flow_dissector_target(struct flow_dissector *flow_dissec return ((char *)target_container) + flow_dissector->offset[key_id]; } +static inline void +flow_dissector_init_keys(struct flow_dissector_key_control *key_control, + struct flow_dissector_key_basic *key_basic) +{ + memset(key_control, 0, sizeof(*key_control)); + memset(key_basic, 0, sizeof(*key_basic)); +} + #endif diff --git a/net/sched/cls_flower.c b/net/sched/cls_flower.c index de03b7b49e05..18904313bd4e 100644 --- a/net/sched/cls_flower.c +++ b/net/sched/cls_flower.c @@ -141,6 +141,7 @@ static int fl_classify(struct sk_buff *skb, const struct tcf_proto *tp, if (!atomic_read(&head->ht.nelems)) return -1; + flow_dissector_init_keys(&skb_key.control, &skb_key.basic); fl_clear_masked_range(&skb_key, &head->mask); info = skb_tunnel_info(skb); |