netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH net-next] drop_monitor: Make timestamps y2038 safe
@ 2019-08-23 15:47 Ido Schimmel
  2019-08-23 16:17 ` Neil Horman
                   ` (2 more replies)
  0 siblings, 3 replies; 4+ messages in thread
From: Ido Schimmel @ 2019-08-23 15:47 UTC (permalink / raw)
  To: netdev; +Cc: davem, nhorman, arnd, andrew, ayal, mlxsw, Ido Schimmel

From: Ido Schimmel <idosch@mellanox.com>

Timestamps are currently communicated to user space as 'struct
timespec', which is not considered y2038 safe since it uses a 32-bit
signed value for seconds.

Fix this while the API is still not part of any official kernel release
by using 64-bit nanoseconds timestamps instead.

Fixes: ca30707dee2b ("drop_monitor: Add packet alert mode")
Fixes: 5e58109b1ea4 ("drop_monitor: Add support for packet alert mode for hardware drops")
Signed-off-by: Ido Schimmel <idosch@mellanox.com>
---
Arnd, I have followed your recommendation to use 64-bit nanoseconds
timestamps. I would appreciate it if you could review this change.

Thanks!
---
 include/uapi/linux/net_dropmon.h |  2 +-
 net/core/drop_monitor.c          | 14 ++++++--------
 2 files changed, 7 insertions(+), 9 deletions(-)

diff --git a/include/uapi/linux/net_dropmon.h b/include/uapi/linux/net_dropmon.h
index 75a35dccb675..8bf79a9eb234 100644
--- a/include/uapi/linux/net_dropmon.h
+++ b/include/uapi/linux/net_dropmon.h
@@ -75,7 +75,7 @@ enum net_dm_attr {
 	NET_DM_ATTR_PC,				/* u64 */
 	NET_DM_ATTR_SYMBOL,			/* string */
 	NET_DM_ATTR_IN_PORT,			/* nested */
-	NET_DM_ATTR_TIMESTAMP,			/* struct timespec */
+	NET_DM_ATTR_TIMESTAMP,			/* u64 */
 	NET_DM_ATTR_PROTO,			/* u16 */
 	NET_DM_ATTR_PAYLOAD,			/* binary */
 	NET_DM_ATTR_PAD,
diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c
index bfc024024aa3..cc60cc22e2db 100644
--- a/net/core/drop_monitor.c
+++ b/net/core/drop_monitor.c
@@ -552,7 +552,7 @@ static size_t net_dm_packet_report_size(size_t payload_len)
 	       /* NET_DM_ATTR_IN_PORT */
 	       net_dm_in_port_size() +
 	       /* NET_DM_ATTR_TIMESTAMP */
-	       nla_total_size(sizeof(struct timespec)) +
+	       nla_total_size(sizeof(u64)) +
 	       /* NET_DM_ATTR_ORIG_LEN */
 	       nla_total_size(sizeof(u32)) +
 	       /* NET_DM_ATTR_PROTO */
@@ -592,7 +592,6 @@ static int net_dm_packet_report_fill(struct sk_buff *msg, struct sk_buff *skb,
 	u64 pc = (u64)(uintptr_t) NET_DM_SKB_CB(skb)->pc;
 	char buf[NET_DM_MAX_SYMBOL_LEN];
 	struct nlattr *attr;
-	struct timespec ts;
 	void *hdr;
 	int rc;
 
@@ -615,8 +614,8 @@ static int net_dm_packet_report_fill(struct sk_buff *msg, struct sk_buff *skb,
 	if (rc)
 		goto nla_put_failure;
 
-	if (ktime_to_timespec_cond(skb->tstamp, &ts) &&
-	    nla_put(msg, NET_DM_ATTR_TIMESTAMP, sizeof(ts), &ts))
+	if (nla_put_u64_64bit(msg, NET_DM_ATTR_TIMESTAMP,
+			      ktime_to_ns(skb->tstamp), NET_DM_ATTR_PAD))
 		goto nla_put_failure;
 
 	if (nla_put_u32(msg, NET_DM_ATTR_ORIG_LEN, skb->len))
@@ -716,7 +715,7 @@ net_dm_hw_packet_report_size(size_t payload_len,
 	       /* NET_DM_ATTR_IN_PORT */
 	       net_dm_in_port_size() +
 	       /* NET_DM_ATTR_TIMESTAMP */
-	       nla_total_size(sizeof(struct timespec)) +
+	       nla_total_size(sizeof(u64)) +
 	       /* NET_DM_ATTR_ORIG_LEN */
 	       nla_total_size(sizeof(u32)) +
 	       /* NET_DM_ATTR_PROTO */
@@ -730,7 +729,6 @@ static int net_dm_hw_packet_report_fill(struct sk_buff *msg,
 {
 	struct net_dm_hw_metadata *hw_metadata;
 	struct nlattr *attr;
-	struct timespec ts;
 	void *hdr;
 
 	hw_metadata = NET_DM_SKB_CB(skb)->hw_metadata;
@@ -761,8 +759,8 @@ static int net_dm_hw_packet_report_fill(struct sk_buff *msg,
 			goto nla_put_failure;
 	}
 
-	if (ktime_to_timespec_cond(skb->tstamp, &ts) &&
-	    nla_put(msg, NET_DM_ATTR_TIMESTAMP, sizeof(ts), &ts))
+	if (nla_put_u64_64bit(msg, NET_DM_ATTR_TIMESTAMP,
+			      ktime_to_ns(skb->tstamp), NET_DM_ATTR_PAD))
 		goto nla_put_failure;
 
 	if (nla_put_u32(msg, NET_DM_ATTR_ORIG_LEN, skb->len))
-- 
2.21.0


^ permalink raw reply related	[flat|nested] 4+ messages in thread
* Re: [PATCH net-next] drop_monitor: Make timestamps y2038 safe
  2019-08-23 15:47 [PATCH net-next] drop_monitor: Make timestamps y2038 safe Ido Schimmel
@ 2019-08-23 16:17 ` Neil Horman
  2019-08-23 21:58 ` David Miller
  2019-08-27 13:10 ` Arnd Bergmann
  2 siblings, 0 replies; 4+ messages in thread
From: Neil Horman @ 2019-08-23 16:17 UTC (permalink / raw)
  To: Ido Schimmel; +Cc: netdev, davem, arnd, andrew, ayal, mlxsw, Ido Schimmel

On Fri, Aug 23, 2019 at 06:47:21PM +0300, Ido Schimmel wrote:
> From: Ido Schimmel <idosch@mellanox.com>
> 
> Timestamps are currently communicated to user space as 'struct
> timespec', which is not considered y2038 safe since it uses a 32-bit
> signed value for seconds.
> 
> Fix this while the API is still not part of any official kernel release
> by using 64-bit nanoseconds timestamps instead.
> 
> Fixes: ca30707dee2b ("drop_monitor: Add packet alert mode")
> Fixes: 5e58109b1ea4 ("drop_monitor: Add support for packet alert mode for hardware drops")
> Signed-off-by: Ido Schimmel <idosch@mellanox.com>
> ---
> Arnd, I have followed your recommendation to use 64-bit nanoseconds
> timestamps. I would appreciate it if you could review this change.
> 
> Thanks!
> ---
>  include/uapi/linux/net_dropmon.h |  2 +-
>  net/core/drop_monitor.c          | 14 ++++++--------
>  2 files changed, 7 insertions(+), 9 deletions(-)
> 
> diff --git a/include/uapi/linux/net_dropmon.h b/include/uapi/linux/net_dropmon.h
> index 75a35dccb675..8bf79a9eb234 100644
> --- a/include/uapi/linux/net_dropmon.h
> +++ b/include/uapi/linux/net_dropmon.h
> @@ -75,7 +75,7 @@ enum net_dm_attr {
>  	NET_DM_ATTR_PC,				/* u64 */
>  	NET_DM_ATTR_SYMBOL,			/* string */
>  	NET_DM_ATTR_IN_PORT,			/* nested */
> -	NET_DM_ATTR_TIMESTAMP,			/* struct timespec */
> +	NET_DM_ATTR_TIMESTAMP,			/* u64 */
>  	NET_DM_ATTR_PROTO,			/* u16 */
>  	NET_DM_ATTR_PAYLOAD,			/* binary */
>  	NET_DM_ATTR_PAD,
> diff --git a/net/core/drop_monitor.c b/net/core/drop_monitor.c
> index bfc024024aa3..cc60cc22e2db 100644
> --- a/net/core/drop_monitor.c
> +++ b/net/core/drop_monitor.c
> @@ -552,7 +552,7 @@ static size_t net_dm_packet_report_size(size_t payload_len)
>  	       /* NET_DM_ATTR_IN_PORT */
>  	       net_dm_in_port_size() +
>  	       /* NET_DM_ATTR_TIMESTAMP */
> -	       nla_total_size(sizeof(struct timespec)) +
> +	       nla_total_size(sizeof(u64)) +
>  	       /* NET_DM_ATTR_ORIG_LEN */
>  	       nla_total_size(sizeof(u32)) +
>  	       /* NET_DM_ATTR_PROTO */
> @@ -592,7 +592,6 @@ static int net_dm_packet_report_fill(struct sk_buff *msg, struct sk_buff *skb,
>  	u64 pc = (u64)(uintptr_t) NET_DM_SKB_CB(skb)->pc;
>  	char buf[NET_DM_MAX_SYMBOL_LEN];
>  	struct nlattr *attr;
> -	struct timespec ts;
>  	void *hdr;
>  	int rc;
>  
> @@ -615,8 +614,8 @@ static int net_dm_packet_report_fill(struct sk_buff *msg, struct sk_buff *skb,
>  	if (rc)
>  		goto nla_put_failure;
>  
> -	if (ktime_to_timespec_cond(skb->tstamp, &ts) &&
> -	    nla_put(msg, NET_DM_ATTR_TIMESTAMP, sizeof(ts), &ts))
> +	if (nla_put_u64_64bit(msg, NET_DM_ATTR_TIMESTAMP,
> +			      ktime_to_ns(skb->tstamp), NET_DM_ATTR_PAD))
>  		goto nla_put_failure;
>  
>  	if (nla_put_u32(msg, NET_DM_ATTR_ORIG_LEN, skb->len))
> @@ -716,7 +715,7 @@ net_dm_hw_packet_report_size(size_t payload_len,
>  	       /* NET_DM_ATTR_IN_PORT */
>  	       net_dm_in_port_size() +
>  	       /* NET_DM_ATTR_TIMESTAMP */
> -	       nla_total_size(sizeof(struct timespec)) +
> +	       nla_total_size(sizeof(u64)) +
>  	       /* NET_DM_ATTR_ORIG_LEN */
>  	       nla_total_size(sizeof(u32)) +
>  	       /* NET_DM_ATTR_PROTO */
> @@ -730,7 +729,6 @@ static int net_dm_hw_packet_report_fill(struct sk_buff *msg,
>  {
>  	struct net_dm_hw_metadata *hw_metadata;
>  	struct nlattr *attr;
> -	struct timespec ts;
>  	void *hdr;
>  
>  	hw_metadata = NET_DM_SKB_CB(skb)->hw_metadata;
> @@ -761,8 +759,8 @@ static int net_dm_hw_packet_report_fill(struct sk_buff *msg,
>  			goto nla_put_failure;
>  	}
>  
> -	if (ktime_to_timespec_cond(skb->tstamp, &ts) &&
> -	    nla_put(msg, NET_DM_ATTR_TIMESTAMP, sizeof(ts), &ts))
> +	if (nla_put_u64_64bit(msg, NET_DM_ATTR_TIMESTAMP,
> +			      ktime_to_ns(skb->tstamp), NET_DM_ATTR_PAD))
>  		goto nla_put_failure;
>  
>  	if (nla_put_u32(msg, NET_DM_ATTR_ORIG_LEN, skb->len))
> -- 
> 2.21.0
> 
> 
Acked-by: Neil Horman <nhorman@tuxdriver.com>

^ permalink raw reply	[flat|nested] 4+ messages in thread
* Re: [PATCH net-next] drop_monitor: Make timestamps y2038 safe
  2019-08-23 15:47 [PATCH net-next] drop_monitor: Make timestamps y2038 safe Ido Schimmel
  2019-08-23 16:17 ` Neil Horman
@ 2019-08-23 21:58 ` David Miller
  2019-08-27 13:10 ` Arnd Bergmann
  2 siblings, 0 replies; 4+ messages in thread
From: David Miller @ 2019-08-23 21:58 UTC (permalink / raw)
  To: idosch; +Cc: netdev, nhorman, arnd, andrew, ayal, mlxsw, idosch

From: Ido Schimmel <idosch@idosch.org>
Date: Fri, 23 Aug 2019 18:47:21 +0300

> From: Ido Schimmel <idosch@mellanox.com>
> 
> Timestamps are currently communicated to user space as 'struct
> timespec', which is not considered y2038 safe since it uses a 32-bit
> signed value for seconds.
> 
> Fix this while the API is still not part of any official kernel release
> by using 64-bit nanoseconds timestamps instead.
> 
> Fixes: ca30707dee2b ("drop_monitor: Add packet alert mode")
> Fixes: 5e58109b1ea4 ("drop_monitor: Add support for packet alert mode for hardware drops")
> Signed-off-by: Ido Schimmel <idosch@mellanox.com>

Applied, thanks Ido.

^ permalink raw reply	[flat|nested] 4+ messages in thread
* Re: [PATCH net-next] drop_monitor: Make timestamps y2038 safe
  2019-08-23 15:47 [PATCH net-next] drop_monitor: Make timestamps y2038 safe Ido Schimmel
  2019-08-23 16:17 ` Neil Horman
  2019-08-23 21:58 ` David Miller
@ 2019-08-27 13:10 ` Arnd Bergmann
  2 siblings, 0 replies; 4+ messages in thread
From: Arnd Bergmann @ 2019-08-27 13:10 UTC (permalink / raw)
  To: Ido Schimmel
  Cc: Networking, David Miller, Neil Horman, Andrew Lunn, Aya Levin,
	mlxsw, Ido Schimmel

On Fri, Aug 23, 2019 at 5:48 PM Ido Schimmel <idosch@idosch.org> wrote:
>
> From: Ido Schimmel <idosch@mellanox.com>
>
> Timestamps are currently communicated to user space as 'struct
> timespec', which is not considered y2038 safe since it uses a 32-bit
> signed value for seconds.
>
> Fix this while the API is still not part of any official kernel release
> by using 64-bit nanoseconds timestamps instead.
>
> Fixes: ca30707dee2b ("drop_monitor: Add packet alert mode")
> Fixes: 5e58109b1ea4 ("drop_monitor: Add support for packet alert mode for hardware drops")
> Signed-off-by: Ido Schimmel <idosch@mellanox.com>
> ---
> Arnd, I have followed your recommendation to use 64-bit nanoseconds
> timestamps. I would appreciate it if you could review this change.

somewhat late reply:


> @@ -761,8 +759,8 @@ static int net_dm_hw_packet_report_fill(struct sk_buff *msg,
>                         goto nla_put_failure;
>         }
>
> -       if (ktime_to_timespec_cond(skb->tstamp, &ts) &&
> -           nla_put(msg, NET_DM_ATTR_TIMESTAMP, sizeof(ts), &ts))
> +       if (nla_put_u64_64bit(msg, NET_DM_ATTR_TIMESTAMP,
> +                             ktime_to_ns(skb->tstamp), NET_DM_ATTR_PAD))
>                 goto nla_put_failure;
>
>         if (nla_put_u32(msg, NET_DM_ATTR_ORIG_LEN, skb->len))

Yes, this looks reasonable. I guess since we take the skb timestamps
in CLOCK_REALTIME, there is little point in trying to use
CLOCK_MONOTONIC in the user interface.

64-bit nanoseconds are safe for a few hundred years.

       Arnd

^ permalink raw reply	[flat|nested] 4+ messages in thread
end of thread, other threads:[~2019-08-27 13:11 UTC | newest]

Thread overview: 4+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2019-08-23 15:47 [PATCH net-next] drop_monitor: Make timestamps y2038 safe Ido Schimmel
2019-08-23 16:17 ` Neil Horman
2019-08-23 21:58 ` David Miller
2019-08-27 13:10 ` Arnd Bergmann

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).