diff options
| author | Eric Dumazet <edumazet@google.com> | 2015-03-12 02:42:02 +0100 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2015-03-12 04:51:18 +0100 |
| commit | c29390c6dfeee0944ac6b5610ebbe403944378fc (patch) | |
| tree | befe951b043be948957abb1db65cee36dd7a379b | |
| parent | xen-netback: notify immediately after pushing Tx response. (diff) | |
| download | linux-c29390c6dfeee0944ac6b5610ebbe403944378fc.tar.xz linux-c29390c6dfeee0944ac6b5610ebbe403944378fc.zip | |
xps: must clear sender_cpu before forwarding
John reported that my previous commit added a regression
on his router.
This is because sender_cpu & napi_id share a common location,
so get_xps_queue() can see garbage and perform an out of bound access.
We need to make sure sender_cpu is cleared before doing the transmit,
otherwise any NIC busy poll enabled (skb_mark_napi_id()) can trigger
this bug.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: John <jw@nuclearfallout.net>
Bisected-by: John <jw@nuclearfallout.net>
Fixes: 2bd82484bb4c ("xps: fix xps for stacked devices")
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | include/linux/skbuff.h | 7 | ||||
| -rw-r--r-- | net/core/skbuff.c | 2 | ||||
| -rw-r--r-- | net/ipv4/ip_forward.c | 1 | ||||
| -rw-r--r-- | net/ipv6/ip6_output.c | 1 |
4 files changed, 10 insertions, 1 deletions
diff --git a/include/linux/skbuff.h b/include/linux/skbuff.h index 30007afe70b3..f54d6659713a 100644 --- a/include/linux/skbuff.h +++ b/include/linux/skbuff.h @@ -948,6 +948,13 @@ static inline void skb_copy_hash(struct sk_buff *to, const struct sk_buff *from) to->l4_hash = from->l4_hash; }; +static inline void skb_sender_cpu_clear(struct sk_buff *skb) +{ +#ifdef CONFIG_XPS + skb->sender_cpu = 0; +#endif +} + #ifdef NET_SKBUFF_DATA_USES_OFFSET static inline unsigned char *skb_end_pointer(const struct sk_buff *skb) { diff --git a/net/core/skbuff.c b/net/core/skbuff.c index f80507823531..434e78e5254d 100644 --- a/net/core/skbuff.c +++ b/net/core/skbuff.c @@ -4173,7 +4173,7 @@ void skb_scrub_packet(struct sk_buff *skb, bool xnet) skb->ignore_df = 0; skb_dst_drop(skb); skb->mark = 0; - skb->sender_cpu = 0; + skb_sender_cpu_clear(skb); skb_init_secmark(skb); secpath_reset(skb); nf_reset(skb); diff --git a/net/ipv4/ip_forward.c b/net/ipv4/ip_forward.c index 787b3c294ce6..d9bc28ac5d1b 100644 --- a/net/ipv4/ip_forward.c +++ b/net/ipv4/ip_forward.c @@ -67,6 +67,7 @@ static int ip_forward_finish(struct sk_buff *skb) if (unlikely(opt->optlen)) ip_forward_options(skb); + skb_sender_cpu_clear(skb); return dst_output(skb); } diff --git a/net/ipv6/ip6_output.c b/net/ipv6/ip6_output.c index 0a04a37305d5..7e80b61b51ff 100644 --- a/net/ipv6/ip6_output.c +++ b/net/ipv6/ip6_output.c @@ -318,6 +318,7 @@ static int ip6_forward_proxy_check(struct sk_buff *skb) static inline int ip6_forward_finish(struct sk_buff *skb) { + skb_sender_cpu_clear(skb); return dst_output(skb); } |