* [PATCH] net: check net.core.somaxconn sysctl values
@ 2013-07-31 13:57 Roman Gushchin
2013-07-31 14:37 ` Eric Dumazet
2013-08-01 0:10 ` David Miller
0 siblings, 2 replies; 9+ messages in thread
From: Roman Gushchin @ 2013-07-31 13:57 UTC (permalink / raw)
To: David S. Miller, Eric Dumazet, raise.sail, ebiederm, netdev,
linux-kernel
It's possible to assign an invalid value to the net.core.somaxconn
sysctl variable, because there is no checks at all.
The sk_max_ack_backlog field of the sock structure is defined as
unsigned short. Therefore, the backlog argument in inet_listen()
shouldn't exceed USHRT_MAX. The backlog argument in the listen() syscall
is truncated to the somaxconn value. So, the somaxconn value shouldn't
exceed 65535 (USHRT_MAX).
Also, negative values of somaxconn are meaningless.
before:
$ sysctl -w net.core.somaxconn=256
net.core.somaxconn = 256
$ sysctl -w net.core.somaxconn=65536
net.core.somaxconn = 65536
$ sysctl -w net.core.somaxconn=-100
net.core.somaxconn = -100
after:
$ sysctl -w net.core.somaxconn=256
net.core.somaxconn = 256
$ sysctl -w net.core.somaxconn=65536
error: "Invalid argument" setting key "net.core.somaxconn"
$ sysctl -w net.core.somaxconn=-100
error: "Invalid argument" setting key "net.core.somaxconn"
Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
---
net/core/sysctl_net_core.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
index cfdb46a..2ff093b 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -20,7 +20,9 @@
#include <net/sock.h>
#include <net/net_ratelimit.h>
+static int zero = 0;
static int one = 1;
+static int ushort_max = USHRT_MAX;
#ifdef CONFIG_RPS
static int rps_sock_flow_sysctl(ctl_table *table, int write,
@@ -204,7 +206,9 @@ static struct ctl_table netns_core_table[] = {
.data = &init_net.core.sysctl_somaxconn,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec
+ .extra1 = &zero,
+ .extra2 = &ushort_max,
+ .proc_handler = proc_dointvec_minmax
},
{ }
};
--
1.8.1.2
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH] net: check net.core.somaxconn sysctl values
2013-07-31 13:57 [PATCH] net: check net.core.somaxconn sysctl values Roman Gushchin
@ 2013-07-31 14:37 ` Eric Dumazet
2013-07-31 15:03 ` Roman Gushchin
2013-08-01 0:10 ` David Miller
1 sibling, 1 reply; 9+ messages in thread
From: Eric Dumazet @ 2013-07-31 14:37 UTC (permalink / raw)
To: Roman Gushchin
Cc: David S. Miller, raise.sail, ebiederm, netdev, linux-kernel
On Wed, 2013-07-31 at 17:57 +0400, Roman Gushchin wrote:
> It's possible to assign an invalid value to the net.core.somaxconn
> sysctl variable, because there is no checks at all.
>
> The sk_max_ack_backlog field of the sock structure is defined as
> unsigned short. Therefore, the backlog argument in inet_listen()
> shouldn't exceed USHRT_MAX. The backlog argument in the listen() syscall
> is truncated to the somaxconn value. So, the somaxconn value shouldn't
> exceed 65535 (USHRT_MAX).
> Also, negative values of somaxconn are meaningless.
>
> before:
> $ sysctl -w net.core.somaxconn=256
> net.core.somaxconn = 256
> $ sysctl -w net.core.somaxconn=65536
> net.core.somaxconn = 65536
> $ sysctl -w net.core.somaxconn=-100
> net.core.somaxconn = -100
>
> after:
> $ sysctl -w net.core.somaxconn=256
> net.core.somaxconn = 256
> $ sysctl -w net.core.somaxconn=65536
> error: "Invalid argument" setting key "net.core.somaxconn"
> $ sysctl -w net.core.somaxconn=-100
> error: "Invalid argument" setting key "net.core.somaxconn"
>
> Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
> ---
> net/core/sysctl_net_core.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
We had a discussion about this one month ago, as Changli Gao posted a
patch. http://patchwork.ozlabs.org/patch/255460/
So proper credits would be nice ;)
Based on a prior patch from Changli Gao
Reported-by: Changli Gao <xiaosuo@gmail.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] net: check net.core.somaxconn sysctl values
2013-07-31 14:37 ` Eric Dumazet
@ 2013-07-31 15:03 ` Roman Gushchin
0 siblings, 0 replies; 9+ messages in thread
From: Roman Gushchin @ 2013-07-31 15:03 UTC (permalink / raw)
To: Eric Dumazet; +Cc: David S. Miller, raise.sail, ebiederm, netdev, linux-kernel
On 31.07.2013 18:37, Eric Dumazet wrote:
> On Wed, 2013-07-31 at 17:57 +0400, Roman Gushchin wrote:
>> It's possible to assign an invalid value to the net.core.somaxconn
>> sysctl variable, because there is no checks at all.
>>
>> The sk_max_ack_backlog field of the sock structure is defined as
>> unsigned short. Therefore, the backlog argument in inet_listen()
>> shouldn't exceed USHRT_MAX. The backlog argument in the listen() syscall
>> is truncated to the somaxconn value. So, the somaxconn value shouldn't
>> exceed 65535 (USHRT_MAX).
>> Also, negative values of somaxconn are meaningless.
>>
>> before:
>> $ sysctl -w net.core.somaxconn=256
>> net.core.somaxconn = 256
>> $ sysctl -w net.core.somaxconn=65536
>> net.core.somaxconn = 65536
>> $ sysctl -w net.core.somaxconn=-100
>> net.core.somaxconn = -100
>>
>> after:
>> $ sysctl -w net.core.somaxconn=256
>> net.core.somaxconn = 256
>> $ sysctl -w net.core.somaxconn=65536
>> error: "Invalid argument" setting key "net.core.somaxconn"
>> $ sysctl -w net.core.somaxconn=-100
>> error: "Invalid argument" setting key "net.core.somaxconn"
>>
>> Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
>> ---
>> net/core/sysctl_net_core.c | 6 +++++-
>> 1 file changed, 5 insertions(+), 1 deletion(-)
>
>
> We had a discussion about this one month ago, as Changli Gao posted a
> patch. http://patchwork.ozlabs.org/patch/255460/
>
> So proper credits would be nice ;)
Ok :)
> Based on a prior patch from Changli Gao
>
> Reported-by: Changli Gao <xiaosuo@gmail.com>
> Suggested-by: Eric Dumazet <edumazet@google.com>
>
> Acked-by: Eric Dumazet <edumazet@google.com>
>
Thanks!
PS I've forwarded your letter back to the lkml by mistake.
Sorry)
Regards,
Roman
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] net: check net.core.somaxconn sysctl values
2013-07-31 13:57 [PATCH] net: check net.core.somaxconn sysctl values Roman Gushchin
2013-07-31 14:37 ` Eric Dumazet
@ 2013-08-01 0:10 ` David Miller
2013-08-01 9:04 ` Roman Gushchin
1 sibling, 1 reply; 9+ messages in thread
From: David Miller @ 2013-08-01 0:10 UTC (permalink / raw)
To: klamm; +Cc: eric.dumazet, raise.sail, ebiederm, netdev, linux-kernel
From: Roman Gushchin <klamm@yandex-team.ru>
Date: Wed, 31 Jul 2013 17:57:35 +0400
> ---
> net/core/sysctl_net_core.c | 6 +++++-
> 1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
> index cfdb46a..2ff093b 100644
> --- a/net/core/sysctl_net_core.c
> +++ b/net/core/sysctl_net_core.c
> @@ -20,7 +20,9 @@
This patch is against old sources, please respin it against the current
tree.
Thanks.
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] net: check net.core.somaxconn sysctl values
2013-08-01 0:10 ` David Miller
@ 2013-08-01 9:04 ` Roman Gushchin
2013-08-01 21:18 ` David Miller
0 siblings, 1 reply; 9+ messages in thread
From: Roman Gushchin @ 2013-08-01 9:04 UTC (permalink / raw)
To: David Miller; +Cc: eric.dumazet, raise.sail, ebiederm, netdev, linux-kernel
On 01.08.2013 04:10, David Miller wrote:
> From: Roman Gushchin <klamm@yandex-team.ru>
> Date: Wed, 31 Jul 2013 17:57:35 +0400
>
>> ---
>> net/core/sysctl_net_core.c | 6 +++++-
>> 1 file changed, 5 insertions(+), 1 deletion(-)
>>
>> diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
>> index cfdb46a..2ff093b 100644
>> --- a/net/core/sysctl_net_core.c
>> +++ b/net/core/sysctl_net_core.c
>> @@ -20,7 +20,9 @@
>
> This patch is against old sources, please respin it against the current
> tree.
>
> Thanks.
>
net: check net.core.somaxconn sysctl values
It's possible to assign an invalid value to the net.core.somaxconn
sysctl variable, because there is no checks at all.
The sk_max_ack_backlog field of the sock structure is defined as
unsigned short. Therefore, the backlog argument in inet_listen()
shouldn't exceed USHRT_MAX. The backlog argument in the listen() syscall
is truncated to the somaxconn value. So, the somaxconn value shouldn't
exceed 65535 (USHRT_MAX).
Also, negative values of somaxconn are meaningless.
before:
$ sysctl -w net.core.somaxconn=256
net.core.somaxconn = 256
$ sysctl -w net.core.somaxconn=65536
net.core.somaxconn = 65536
$ sysctl -w net.core.somaxconn=-100
net.core.somaxconn = -100
after:
$ sysctl -w net.core.somaxconn=256
net.core.somaxconn = 256
$ sysctl -w net.core.somaxconn=65536
error: "Invalid argument" setting key "net.core.somaxconn"
$ sysctl -w net.core.somaxconn=-100
error: "Invalid argument" setting key "net.core.somaxconn"
Based on a prior patch from Changli Gao.
Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
Reported-by: Changli Gao <xiaosuo@gmail.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
---
net/core/sysctl_net_core.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
index 6609686..7c37dcd 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -21,7 +21,9 @@
#include <net/net_ratelimit.h>
#include <net/busy_poll.h>
+static int zero = 0;
static int one = 1;
+static int ushort_max = USHRT_MAX;
#ifdef CONFIG_RPS
static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
@@ -339,7 +341,9 @@ static struct ctl_table netns_core_table[] = {
.data = &init_net.core.sysctl_somaxconn,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec
+ .extra1 = &zero,
+ .extra2 = &ushort_max,
+ .proc_handler = proc_dointvec_minmax
},
{ }
};
--
1.8.1.2
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH] net: check net.core.somaxconn sysctl values
2013-08-01 9:04 ` Roman Gushchin
@ 2013-08-01 21:18 ` David Miller
2013-08-02 14:36 ` Roman Gushchin
0 siblings, 1 reply; 9+ messages in thread
From: David Miller @ 2013-08-01 21:18 UTC (permalink / raw)
To: klamm; +Cc: eric.dumazet, raise.sail, ebiederm, netdev, linux-kernel
From: Roman Gushchin <klamm@yandex-team.ru>
Date: Thu, 01 Aug 2013 13:04:16 +0400
> On 01.08.2013 04:10, David Miller wrote:
>> From: Roman Gushchin <klamm@yandex-team.ru>
>> Date: Wed, 31 Jul 2013 17:57:35 +0400
>>
>>> ---
>>> net/core/sysctl_net_core.c | 6 +++++-
>>> 1 file changed, 5 insertions(+), 1 deletion(-)
>>>
>>> diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
>>> index cfdb46a..2ff093b 100644
>>> --- a/net/core/sysctl_net_core.c
>>> +++ b/net/core/sysctl_net_core.c
>>> @@ -20,7 +20,9 @@
>>
>> This patch is against old sources, please respin it against the
>> current
>> tree.
>>
>> Thanks.
>>
>
> net: check net.core.somaxconn sysctl values
Still doesn't apply, and it's because your email client has corrupted
the patch.
Please read Documentation/email-clients.txt to learn how to fix this
problem, and then send a test patch to yourself.
Only when you can successfully apply the test patch you send to
yourself should you repost your patch here.
Thanks.
^ permalink raw reply [flat|nested] 9+ messages in thread
* [PATCH] net: check net.core.somaxconn sysctl values
2013-08-01 21:18 ` David Miller
@ 2013-08-02 14:36 ` Roman Gushchin
2013-08-02 22:19 ` David Miller
0 siblings, 1 reply; 9+ messages in thread
From: Roman Gushchin @ 2013-08-02 14:36 UTC (permalink / raw)
To: davem
Cc: eric.dumazet, raise.sail, ebiederm, netdev, linux-kernel,
Roman Gushchin
It's possible to assign an invalid value to the net.core.somaxconn
sysctl variable, because there is no checks at all.
The sk_max_ack_backlog field of the sock structure is defined as
unsigned short. Therefore, the backlog argument in inet_listen()
shouldn't exceed USHRT_MAX. The backlog argument in the listen() syscall
is truncated to the somaxconn value. So, the somaxconn value shouldn't
exceed 65535 (USHRT_MAX).
Also, negative values of somaxconn are meaningless.
before:
$ sysctl -w net.core.somaxconn=256
net.core.somaxconn = 256
$ sysctl -w net.core.somaxconn=65536
net.core.somaxconn = 65536
$ sysctl -w net.core.somaxconn=-100
net.core.somaxconn = -100
after:
$ sysctl -w net.core.somaxconn=256
net.core.somaxconn = 256
$ sysctl -w net.core.somaxconn=65536
error: "Invalid argument" setting key "net.core.somaxconn"
$ sysctl -w net.core.somaxconn=-100
error: "Invalid argument" setting key "net.core.somaxconn"
Based on a prior patch from Changli Gao.
Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
Reported-by: Changli Gao <xiaosuo@gmail.com>
Suggested-by: Eric Dumazet <edumazet@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
---
net/core/sysctl_net_core.c | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/net/core/sysctl_net_core.c b/net/core/sysctl_net_core.c
index 6609686..7c37dcd 100644
--- a/net/core/sysctl_net_core.c
+++ b/net/core/sysctl_net_core.c
@@ -21,7 +21,9 @@
#include <net/net_ratelimit.h>
#include <net/busy_poll.h>
+static int zero = 0;
static int one = 1;
+static int ushort_max = USHRT_MAX;
#ifdef CONFIG_RPS
static int rps_sock_flow_sysctl(struct ctl_table *table, int write,
@@ -339,7 +341,9 @@ static struct ctl_table netns_core_table[] = {
.data = &init_net.core.sysctl_somaxconn,
.maxlen = sizeof(int),
.mode = 0644,
- .proc_handler = proc_dointvec
+ .extra1 = &zero,
+ .extra2 = &ushort_max,
+ .proc_handler = proc_dointvec_minmax
},
{ }
};
--
1.8.1.2
^ permalink raw reply related [flat|nested] 9+ messages in thread* Re: [PATCH] net: check net.core.somaxconn sysctl values
2013-08-02 14:36 ` Roman Gushchin
@ 2013-08-02 22:19 ` David Miller
2013-08-03 10:14 ` Roman Gushchin
0 siblings, 1 reply; 9+ messages in thread
From: David Miller @ 2013-08-02 22:19 UTC (permalink / raw)
To: klamm; +Cc: eric.dumazet, raise.sail, ebiederm, netdev, linux-kernel
From: Roman Gushchin <klamm@yandex-team.ru>
Date: Fri, 2 Aug 2013 18:36:40 +0400
> It's possible to assign an invalid value to the net.core.somaxconn
> sysctl variable, because there is no checks at all.
>
> The sk_max_ack_backlog field of the sock structure is defined as
> unsigned short. Therefore, the backlog argument in inet_listen()
> shouldn't exceed USHRT_MAX. The backlog argument in the listen() syscall
> is truncated to the somaxconn value. So, the somaxconn value shouldn't
> exceed 65535 (USHRT_MAX).
> Also, negative values of somaxconn are meaningless.
>
> before:
> $ sysctl -w net.core.somaxconn=256
> net.core.somaxconn = 256
> $ sysctl -w net.core.somaxconn=65536
> net.core.somaxconn = 65536
> $ sysctl -w net.core.somaxconn=-100
> net.core.somaxconn = -100
>
> after:
> $ sysctl -w net.core.somaxconn=256
> net.core.somaxconn = 256
> $ sysctl -w net.core.somaxconn=65536
> error: "Invalid argument" setting key "net.core.somaxconn"
> $ sysctl -w net.core.somaxconn=-100
> error: "Invalid argument" setting key "net.core.somaxconn"
>
> Based on a prior patch from Changli Gao.
>
> Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
> Reported-by: Changli Gao <xiaosuo@gmail.com>
> Suggested-by: Eric Dumazet <edumazet@google.com>
> Acked-by: Eric Dumazet <edumazet@google.com>
Applied, thanks.
^ permalink raw reply [flat|nested] 9+ messages in thread
* Re: [PATCH] net: check net.core.somaxconn sysctl values
2013-08-02 22:19 ` David Miller
@ 2013-08-03 10:14 ` Roman Gushchin
0 siblings, 0 replies; 9+ messages in thread
From: Roman Gushchin @ 2013-08-03 10:14 UTC (permalink / raw)
To: David Miller; +Cc: eric.dumazet, raise.sail, ebiederm, netdev, linux-kernel
On 03.08.2013 02:19, David Miller wrote:
> From: Roman Gushchin <klamm@yandex-team.ru>
> Date: Fri, 2 Aug 2013 18:36:40 +0400
>
>> It's possible to assign an invalid value to the net.core.somaxconn
>> sysctl variable, because there is no checks at all.
>>
>> The sk_max_ack_backlog field of the sock structure is defined as
>> unsigned short. Therefore, the backlog argument in inet_listen()
>> shouldn't exceed USHRT_MAX. The backlog argument in the listen() syscall
>> is truncated to the somaxconn value. So, the somaxconn value shouldn't
>> exceed 65535 (USHRT_MAX).
>> Also, negative values of somaxconn are meaningless.
>>
>> before:
>> $ sysctl -w net.core.somaxconn=256
>> net.core.somaxconn = 256
>> $ sysctl -w net.core.somaxconn=65536
>> net.core.somaxconn = 65536
>> $ sysctl -w net.core.somaxconn=-100
>> net.core.somaxconn = -100
>>
>> after:
>> $ sysctl -w net.core.somaxconn=256
>> net.core.somaxconn = 256
>> $ sysctl -w net.core.somaxconn=65536
>> error: "Invalid argument" setting key "net.core.somaxconn"
>> $ sysctl -w net.core.somaxconn=-100
>> error: "Invalid argument" setting key "net.core.somaxconn"
>>
>> Based on a prior patch from Changli Gao.
>>
>> Signed-off-by: Roman Gushchin <klamm@yandex-team.ru>
>> Reported-by: Changli Gao <xiaosuo@gmail.com>
>> Suggested-by: Eric Dumazet <edumazet@google.com>
>> Acked-by: Eric Dumazet <edumazet@google.com>
>
> Applied, thanks.
Thank you!
Regards,
Roman
> --
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^ permalink raw reply [flat|nested] 9+ messages in thread
end of thread, other threads:[~2013-08-03 10:14 UTC | newest]
Thread overview: 9+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-07-31 13:57 [PATCH] net: check net.core.somaxconn sysctl values Roman Gushchin
2013-07-31 14:37 ` Eric Dumazet
2013-07-31 15:03 ` Roman Gushchin
2013-08-01 0:10 ` David Miller
2013-08-01 9:04 ` Roman Gushchin
2013-08-01 21:18 ` David Miller
2013-08-02 14:36 ` Roman Gushchin
2013-08-02 22:19 ` David Miller
2013-08-03 10:14 ` Roman Gushchin
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