* [PATCH] net: Fix sk_dst_check() to reset the obsolete dst_entry of a socket.
@ 2010-10-06 7:27 Chung-Yih Wang (王崇懿)
2010-10-06 7:35 ` David Miller
0 siblings, 1 reply; 6+ messages in thread
From: Chung-Yih Wang (王崇懿) @ 2010-10-06 7:27 UTC (permalink / raw)
To: netdev; +Cc: linux-kernel
The issue is caused by the CL d11a4dc18bf41719c9f0d7ed494d295dd2973b92
which will never reset the dst_entry of a socket if its current entry
is freed(obsolete) for ipv4. This will block the socket's traffic
instead of looking up a new dst_entry.
Signed-off-by: Chung-yih Wang <cywang@google.com>
---
diff --git a/net/core/sock.c b/net/core/sock.c
index ef30e9d..b508819 100644
--- a/net/core/sock.c
+++ b/net/core/sock.c
@@ -382,7 +382,8 @@ struct dst_entry *__sk_dst_check(struct sock *sk,
u32 cookie)
{
struct dst_entry *dst = __sk_dst_get(sk);
- if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
+ if (dst && dst->obsolete && ((dst->obsolete > 0) ||
+ (dst->ops->check(dst, cookie) == NULL))) {
sk_tx_queue_clear(sk);
rcu_assign_pointer(sk->sk_dst_cache, NULL);
dst_release(dst);
@@ -397,7 +398,8 @@ struct dst_entry *sk_dst_check(struct sock *sk, u32 cookie)
{
struct dst_entry *dst = sk_dst_get(sk);
- if (dst && dst->obsolete && dst->ops->check(dst, cookie) == NULL) {
+ if (dst && dst->obsolete && ((dst->obsolete > 0) ||
+ (dst->ops->check(dst, cookie) == NULL))) {
sk_dst_reset(sk);
dst_release(dst);
return NULL;
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] net: Fix sk_dst_check() to reset the obsolete dst_entry of a socket.
2010-10-06 7:27 [PATCH] net: Fix sk_dst_check() to reset the obsolete dst_entry of a socket Chung-Yih Wang (王崇懿)
@ 2010-10-06 7:35 ` David Miller
2010-10-06 7:47 ` Chung-Yih Wang (王崇懿)
0 siblings, 1 reply; 6+ messages in thread
From: David Miller @ 2010-10-06 7:35 UTC (permalink / raw)
To: cywang; +Cc: netdev, linux-kernel, timo.teras
This should have been fixed by:
--------------------
commit ae2688d59b5f861dc70a091d003773975d2ae7fb
Author: Jianzhao Wang <jianzhao.wang@6wind.com>
Date: Wed Sep 8 14:35:43 2010 -0700
net: blackhole route should always be recalculated
Blackhole routes are used when xfrm_lookup() returns -EREMOTE (error
triggered by IKE for example), hence this kind of route is always
temporary and so we should check if a better route exists for next
packets.
Bug has been introduced by commit d11a4dc18bf41719c9f0d7ed494d295dd2973b92.
Signed-off-by: Jianzhao Wang <jianzhao.wang@6wind.com>
Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 3f56b6e..6298f75 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -2738,6 +2738,11 @@ slow_output:
}
EXPORT_SYMBOL_GPL(__ip_route_output_key);
+static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
+{
+ return NULL;
+}
+
static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
{
}
@@ -2746,7 +2751,7 @@ static struct dst_ops ipv4_dst_blackhole_ops = {
.family = AF_INET,
.protocol = cpu_to_be16(ETH_P_IP),
.destroy = ipv4_dst_destroy,
- .check = ipv4_dst_check,
+ .check = ipv4_blackhole_dst_check,
.update_pmtu = ipv4_rt_blackhole_update_pmtu,
.entries = ATOMIC_INIT(0),
};
^ permalink raw reply related [flat|nested] 6+ messages in thread
* Re: [PATCH] net: Fix sk_dst_check() to reset the obsolete dst_entry of a socket.
2010-10-06 7:35 ` David Miller
@ 2010-10-06 7:47 ` Chung-Yih Wang (王崇懿)
2010-10-06 9:47 ` Chung-Yih Wang (王崇懿)
0 siblings, 1 reply; 6+ messages in thread
From: Chung-Yih Wang (王崇懿) @ 2010-10-06 7:47 UTC (permalink / raw)
To: David Miller; +Cc: netdev, linux-kernel, timo.teras
In fact, that is what I intent to change originally. However, consider
Timo's issue, I intent to submit this patch instead.
On Wed, Oct 6, 2010 at 12:35 AM, David Miller <davem@davemloft.net> wrote:
>
> This should have been fixed by:
>
> --------------------
> commit ae2688d59b5f861dc70a091d003773975d2ae7fb
> Author: Jianzhao Wang <jianzhao.wang@6wind.com>
> Date: Wed Sep 8 14:35:43 2010 -0700
>
> net: blackhole route should always be recalculated
>
> Blackhole routes are used when xfrm_lookup() returns -EREMOTE (error
> triggered by IKE for example), hence this kind of route is always
> temporary and so we should check if a better route exists for next
> packets.
> Bug has been introduced by commit d11a4dc18bf41719c9f0d7ed494d295dd2973b92.
>
> Signed-off-by: Jianzhao Wang <jianzhao.wang@6wind.com>
> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
> Signed-off-by: David S. Miller <davem@davemloft.net>
>
> diff --git a/net/ipv4/route.c b/net/ipv4/route.c
> index 3f56b6e..6298f75 100644
> --- a/net/ipv4/route.c
> +++ b/net/ipv4/route.c
> @@ -2738,6 +2738,11 @@ slow_output:
> }
> EXPORT_SYMBOL_GPL(__ip_route_output_key);
>
> +static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
> +{
> + return NULL;
> +}
> +
> static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
> {
> }
> @@ -2746,7 +2751,7 @@ static struct dst_ops ipv4_dst_blackhole_ops = {
> .family = AF_INET,
> .protocol = cpu_to_be16(ETH_P_IP),
> .destroy = ipv4_dst_destroy,
> - .check = ipv4_dst_check,
> + .check = ipv4_blackhole_dst_check,
> .update_pmtu = ipv4_rt_blackhole_update_pmtu,
> .entries = ATOMIC_INIT(0),
> };
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] net: Fix sk_dst_check() to reset the obsolete dst_entry of a socket.
2010-10-06 7:47 ` Chung-Yih Wang (王崇懿)
@ 2010-10-06 9:47 ` Chung-Yih Wang (王崇懿)
2010-10-07 19:37 ` Chung-Yih Wang (王崇懿)
0 siblings, 1 reply; 6+ messages in thread
From: Chung-Yih Wang (王崇懿) @ 2010-10-06 9:47 UTC (permalink / raw)
To: David Miller; +Cc: netdev, linux-kernel, timo.teras
I did not pay attention to the CL, actually that did not fix the issue
I encountered. I have a connected UDP socket which will not escape
from the "blackhole" since it will never enter the ipv4_blackhole
function.
In udp_sendmsg(), if the socket is connected one and the dst entry is
obsolete, you will never have a chance to reset the socket's dst entry
since rt will not be NULL.
udp_sendmsg() {
....
if (connected)
rt = (struct rtable *)sk_dst_check(sk, 0);
if (rt == NULL) {
... blackhole_function_will_be_executed_here?
}
...
}
On Wed, Oct 6, 2010 at 12:47 AM, Chung-Yih Wang (王崇懿) <cywang@google.com> wrote:
> In fact, that is what I intent to change originally. However, consider
> Timo's issue, I intent to submit this patch instead.
>
> On Wed, Oct 6, 2010 at 12:35 AM, David Miller <davem@davemloft.net> wrote:
>>
>> This should have been fixed by:
>>
>> --------------------
>> commit ae2688d59b5f861dc70a091d003773975d2ae7fb
>> Author: Jianzhao Wang <jianzhao.wang@6wind.com>
>> Date: Wed Sep 8 14:35:43 2010 -0700
>>
>> net: blackhole route should always be recalculated
>>
>> Blackhole routes are used when xfrm_lookup() returns -EREMOTE (error
>> triggered by IKE for example), hence this kind of route is always
>> temporary and so we should check if a better route exists for next
>> packets.
>> Bug has been introduced by commit d11a4dc18bf41719c9f0d7ed494d295dd2973b92.
>>
>> Signed-off-by: Jianzhao Wang <jianzhao.wang@6wind.com>
>> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
>> Signed-off-by: David S. Miller <davem@davemloft.net>
>>
>> diff --git a/net/ipv4/route.c b/net/ipv4/route.c
>> index 3f56b6e..6298f75 100644
>> --- a/net/ipv4/route.c
>> +++ b/net/ipv4/route.c
>> @@ -2738,6 +2738,11 @@ slow_output:
>> }
>> EXPORT_SYMBOL_GPL(__ip_route_output_key);
>>
>> +static struct dst_entry *ipv4_blackhole_dst_check(struct dst_entry *dst, u32 cookie)
>> +{
>> + return NULL;
>> +}
>> +
>> static void ipv4_rt_blackhole_update_pmtu(struct dst_entry *dst, u32 mtu)
>> {
>> }
>> @@ -2746,7 +2751,7 @@ static struct dst_ops ipv4_dst_blackhole_ops = {
>> .family = AF_INET,
>> .protocol = cpu_to_be16(ETH_P_IP),
>> .destroy = ipv4_dst_destroy,
>> - .check = ipv4_dst_check,
>> + .check = ipv4_blackhole_dst_check,
>> .update_pmtu = ipv4_rt_blackhole_update_pmtu,
>> .entries = ATOMIC_INIT(0),
>> };
>>
>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] net: Fix sk_dst_check() to reset the obsolete dst_entry of a socket.
2010-10-06 9:47 ` Chung-Yih Wang (王崇懿)
@ 2010-10-07 19:37 ` Chung-Yih Wang (王崇懿)
2010-10-10 1:10 ` Chung-Yih Wang (王崇懿)
0 siblings, 1 reply; 6+ messages in thread
From: Chung-Yih Wang (王崇懿) @ 2010-10-07 19:37 UTC (permalink / raw)
To: David Miller; +Cc: netdev, linux-kernel, timo.teras
As I am testing the l2tp/ipsec client(it is working fine on 2.6.32 but
failed on 2.6.35 with the same client). Please see the following log
dump for sk_dst_check().
<2>[ 201.390289] ==== sk_dst_check sk=C7485800 dst=C717AC60
obsolete=FFFFFFFF cookie=0 check=C0296510
<2>[ 211.247467] ==== sk_dst_check sk=C7485000 dst=C717AC60
obsolete=FFFFFFFF cookie=0 check=C0296510
[Basically, the ipsec tunnel is built and then free the dst_entry for
this l2tp socket. Therefore, the obsolete entry should be reset in
sk_dst_check(). However, the kernel 2.6.35 will do nothing here since
the ipv4_dst_check still return the obsolete entry even if it is
obsolete(dst->obsolete=2)]
<2>[ 216.571350] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<6>[ 218.069396] alg: No test for authenc(hmac(sha1),cbc(des3_ede))
(authenc(hmac(sha1-generic),cbc(des3_ede-generic)))
<6>[ 218.164764] batt: 96%, 4114 mV, 0 mA (-6 avg), 27.2 C, 1305 mAh
<2>[ 218.575561] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 220.580535] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 222.585754] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 224.591522] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 226.599212] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 228.602600] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 230.608062] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 232.613464] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 234.618896] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 236.623504] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 238.628936] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 240.634338] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 242.639709] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 244.645111] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 246.648864] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 248.654693] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 250.660125] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
<2>[ 252.665527] ==== sk_dst_check sk=C7485400 dst=C6F670E0
obsolete=00000002 cookie=0 check=C0296510
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH] net: Fix sk_dst_check() to reset the obsolete dst_entry of a socket.
2010-10-07 19:37 ` Chung-Yih Wang (王崇懿)
@ 2010-10-10 1:10 ` Chung-Yih Wang (王崇懿)
0 siblings, 0 replies; 6+ messages in thread
From: Chung-Yih Wang (王崇懿) @ 2010-10-10 1:10 UTC (permalink / raw)
To: David Miller; +Cc: netdev, linux-kernel, timo.teras
After I gave it a try, that patch worked. Please ignore my patch then. Thanks!
On Thu, Oct 7, 2010 at 12:37 PM, Chung-Yih Wang (王崇懿) <cywang@google.com> wrote:
> As I am testing the l2tp/ipsec client(it is working fine on 2.6.32 but
> failed on 2.6.35 with the same client). Please see the following log
> dump for sk_dst_check().
>
> <2>[ 201.390289] ==== sk_dst_check sk=C7485800 dst=C717AC60
> obsolete=FFFFFFFF cookie=0 check=C0296510
> <2>[ 211.247467] ==== sk_dst_check sk=C7485000 dst=C717AC60
> obsolete=FFFFFFFF cookie=0 check=C0296510
>
> [Basically, the ipsec tunnel is built and then free the dst_entry for
> this l2tp socket. Therefore, the obsolete entry should be reset in
> sk_dst_check(). However, the kernel 2.6.35 will do nothing here since
> the ipv4_dst_check still return the obsolete entry even if it is
> obsolete(dst->obsolete=2)]
>
> <2>[ 216.571350] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <6>[ 218.069396] alg: No test for authenc(hmac(sha1),cbc(des3_ede))
> (authenc(hmac(sha1-generic),cbc(des3_ede-generic)))
> <6>[ 218.164764] batt: 96%, 4114 mV, 0 mA (-6 avg), 27.2 C, 1305 mAh
> <2>[ 218.575561] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 220.580535] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 222.585754] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 224.591522] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 226.599212] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 228.602600] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 230.608062] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 232.613464] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 234.618896] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 236.623504] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 238.628936] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 240.634338] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 242.639709] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 244.645111] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 246.648864] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 248.654693] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 250.660125] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
> <2>[ 252.665527] ==== sk_dst_check sk=C7485400 dst=C6F670E0
> obsolete=00000002 cookie=0 check=C0296510
>
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2010-10-10 1:10 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
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2010-10-06 7:27 [PATCH] net: Fix sk_dst_check() to reset the obsolete dst_entry of a socket Chung-Yih Wang (王崇懿)
2010-10-06 7:35 ` David Miller
2010-10-06 7:47 ` Chung-Yih Wang (王崇懿)
2010-10-06 9:47 ` Chung-Yih Wang (王崇懿)
2010-10-07 19:37 ` Chung-Yih Wang (王崇懿)
2010-10-10 1:10 ` Chung-Yih Wang (王崇懿)
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