[pbs-devel] [PATCH proxmox-backup 1/2] api2/node/termproxy: fix user in worker task

[pbs-devel] [PATCH proxmox-backup 1/2] api2/node/termproxy: fix user in worker task

[Dominik Csapak]

'username' here is without realm, but we really want to use user@realm

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---
 src/api2/node.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/api2/node.rs b/src/api2/node.rs
index b80a661..e6ecc85 100644
--- a/src/api2/node.rs
+++ b/src/api2/node.rs
@@ -137,7 +137,7 @@ async fn termproxy(
     let upid = WorkerTask::spawn(
         "termproxy",
         None,
-        &username,
+        &userid,
         false,
         move |worker| async move {
             // move inside the worker so that it survives and does not close the port
-- 
2.20.1

[pbs-devel] [PATCH proxmox-backup 2/2] api2/node/termproxy: fix zombies on worker abort

[Dominik Csapak]

tokios kill_on_drop sometimes leaves zombies around, especially
when there is not another tokio::process::Command spawned after

so instead of relying on the 'kill_on_drop' feature, we explicitly
kill the child on a worker abort. to be able to do this
we have to use 'tokio::select' instead of 'futures::select' since
the latter requires the future to be fused, which consumes the
child handle, leaving us no possibility to kill it after fusing.
(tokio::select does not need the futures to be fused, so we
can reuse the child future after the select again)

Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
---
 src/api2/node.rs | 27 +++++++++++++++++----------
 1 file changed, 17 insertions(+), 10 deletions(-)

diff --git a/src/api2/node.rs b/src/api2/node.rs
index e6ecc85..011717f 100644
--- a/src/api2/node.rs
+++ b/src/api2/node.rs
@@ -2,10 +2,7 @@ use std::net::TcpListener;
 use std::os::unix::io::AsRawFd;
 
 use anyhow::{bail, format_err, Error};
-use futures::{
-    future::{FutureExt, TryFutureExt},
-    select,
-};
+use futures::future::{FutureExt, TryFutureExt};
 use hyper::body::Body;
 use hyper::http::request::Parts;
 use hyper::upgrade::Upgraded;
@@ -170,7 +167,6 @@ async fn termproxy(
             let mut cmd = tokio::process::Command::new("/usr/bin/termproxy");
 
             cmd.args(&arguments)
-                .kill_on_drop(true)
                 .stdout(std::process::Stdio::piped())
                 .stderr(std::process::Stdio::piped());
 
@@ -197,8 +193,9 @@ async fn termproxy(
                 Ok::<(), Error>(())
             };
 
-            select!{
-                res = child.fuse() => {
+            let mut needs_kill = false;
+            let res = tokio::select!{
+                res = &mut child => {
                     let exit_code = res?;
                     if !exit_code.success() {
                         match exit_code.code() {
@@ -208,10 +205,20 @@ async fn termproxy(
                     }
                     Ok(())
                 },
-                res = stdout_fut.fuse() => res,
-                res = stderr_fut.fuse() => res,
-                res = worker.abort_future().fuse() => res.map_err(Error::from),
+                res = stdout_fut => res,
+                res = stderr_fut => res,
+                res = worker.abort_future() => {
+                    needs_kill = true;
+                    res.map_err(Error::from)
+                }
+            };
+
+            if needs_kill {
+                child.kill()?;
+                child.await?;
             }
+
+            res
         },
     )?;
 
-- 
2.20.1

Re: [pbs-devel] [PATCH proxmox-backup 2/2] api2/node/termproxy: fix zombies on worker abort

[Wolfgang Bumiller]

On Mon, Jul 27, 2020 at 08:54:49AM +0200, Dominik Csapak wrote:
> tokios kill_on_drop sometimes leaves zombies around, especially
> when there is not another tokio::process::Command spawned after
> 
> so instead of relying on the 'kill_on_drop' feature, we explicitly
> kill the child on a worker abort. to be able to do this
> we have to use 'tokio::select' instead of 'futures::select' since
> the latter requires the future to be fused, which consumes the
> child handle, leaving us no possibility to kill it after fusing.
> (tokio::select does not need the futures to be fused, so we
> can reuse the child future after the select again)
> 
> Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
> ---
>  src/api2/node.rs | 27 +++++++++++++++++----------
>  1 file changed, 17 insertions(+), 10 deletions(-)
> 
> diff --git a/src/api2/node.rs b/src/api2/node.rs
> index e6ecc85..011717f 100644
> --- a/src/api2/node.rs
> +++ b/src/api2/node.rs
> @@ -2,10 +2,7 @@ use std::net::TcpListener;
>  use std::os::unix::io::AsRawFd;
>  
>  use anyhow::{bail, format_err, Error};
> -use futures::{
> -    future::{FutureExt, TryFutureExt},
> -    select,
> -};
> +use futures::future::{FutureExt, TryFutureExt};
>  use hyper::body::Body;
>  use hyper::http::request::Parts;
>  use hyper::upgrade::Upgraded;
> @@ -170,7 +167,6 @@ async fn termproxy(
>              let mut cmd = tokio::process::Command::new("/usr/bin/termproxy");
>  
>              cmd.args(&arguments)
> -                .kill_on_drop(true)
>                  .stdout(std::process::Stdio::piped())
>                  .stderr(std::process::Stdio::piped());
>  
> @@ -197,8 +193,9 @@ async fn termproxy(
>                  Ok::<(), Error>(())
>              };
>  
> -            select!{
> -                res = child.fuse() => {
> +            let mut needs_kill = false;
> +            let res = tokio::select!{
> +                res = &mut child => {
>                      let exit_code = res?;
>                      if !exit_code.success() {
>                          match exit_code.code() {
> @@ -208,10 +205,20 @@ async fn termproxy(
>                      }
>                      Ok(())
>                  },
> -                res = stdout_fut.fuse() => res,
> -                res = stderr_fut.fuse() => res,
> -                res = worker.abort_future().fuse() => res.map_err(Error::from),
> +                res = stdout_fut => res,
> +                res = stderr_fut => res,
> +                res = worker.abort_future() => {
> +                    needs_kill = true;
> +                    res.map_err(Error::from)
> +                }
> +            };
> +
> +            if needs_kill {

I think we should log if res is an `Err` at this point, as this would
indicate an *error* with the `abort_future`, which IMO shouldn't happen
but also not quitely discarded which the two `?` below would do (since
they return on error).

> +                child.kill()?;
> +                child.await?;
>              }
> +
> +            res
>          },
>      )?;
>  
> -- 
> 2.20.1

Re: [pbs-devel] [PATCH proxmox-backup 2/2] api2/node/termproxy: fix zombies on worker abort

[Dominik Csapak]

On 7/28/20 2:16 PM, Wolfgang Bumiller wrote:
> On Mon, Jul 27, 2020 at 08:54:49AM +0200, Dominik Csapak wrote:
>> tokios kill_on_drop sometimes leaves zombies around, especially
>> when there is not another tokio::process::Command spawned after
>>
>> so instead of relying on the 'kill_on_drop' feature, we explicitly
>> kill the child on a worker abort. to be able to do this
>> we have to use 'tokio::select' instead of 'futures::select' since
>> the latter requires the future to be fused, which consumes the
>> child handle, leaving us no possibility to kill it after fusing.
>> (tokio::select does not need the futures to be fused, so we
>> can reuse the child future after the select again)
>>
>> Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
>> ---
>>   src/api2/node.rs | 27 +++++++++++++++++----------
>>   1 file changed, 17 insertions(+), 10 deletions(-)
>>
>> diff --git a/src/api2/node.rs b/src/api2/node.rs
>> index e6ecc85..011717f 100644
>> --- a/src/api2/node.rs
>> +++ b/src/api2/node.rs
>> @@ -2,10 +2,7 @@ use std::net::TcpListener;
>>   use std::os::unix::io::AsRawFd;
>>   
>>   use anyhow::{bail, format_err, Error};
>> -use futures::{
>> -    future::{FutureExt, TryFutureExt},
>> -    select,
>> -};
>> +use futures::future::{FutureExt, TryFutureExt};
>>   use hyper::body::Body;
>>   use hyper::http::request::Parts;
>>   use hyper::upgrade::Upgraded;
>> @@ -170,7 +167,6 @@ async fn termproxy(
>>               let mut cmd = tokio::process::Command::new("/usr/bin/termproxy");
>>   
>>               cmd.args(&arguments)
>> -                .kill_on_drop(true)
>>                   .stdout(std::process::Stdio::piped())
>>                   .stderr(std::process::Stdio::piped());
>>   
>> @@ -197,8 +193,9 @@ async fn termproxy(
>>                   Ok::<(), Error>(())
>>               };
>>   
>> -            select!{
>> -                res = child.fuse() => {
>> +            let mut needs_kill = false;
>> +            let res = tokio::select!{
>> +                res = &mut child => {
>>                       let exit_code = res?;
>>                       if !exit_code.success() {
>>                           match exit_code.code() {
>> @@ -208,10 +205,20 @@ async fn termproxy(
>>                       }
>>                       Ok(())
>>                   },
>> -                res = stdout_fut.fuse() => res,
>> -                res = stderr_fut.fuse() => res,
>> -                res = worker.abort_future().fuse() => res.map_err(Error::from),
>> +                res = stdout_fut => res,
>> +                res = stderr_fut => res,
>> +                res = worker.abort_future() => {
>> +                    needs_kill = true;
>> +                    res.map_err(Error::from)
>> +                }
>> +            };
>> +
>> +            if needs_kill {
> 
> I think we should log if res is an `Err` at this point, as this would
> indicate an *error* with the `abort_future`, which IMO shouldn't happen
> but also not quitely discarded which the two `?` below would do (since
> they return on error).

keeping the results is good imo, but i'd rather still return the
result from the future above and log if the kill/await here
fails?
e.g,

if let Err(err) = child.kill() {
     //log
} else if let Err(err) = child.await {
     //log
}

res

?

> 
>> +                child.kill()?;
>> +                child.await?;
>>               }
>> +
>> +            res
>>           },
>>       )?;
>>   
>> -- 
>> 2.20.1

[pbs-devel] applied: [PATCH proxmox-backup 1/2] api2/node/termproxy: fix user in worker task

[Wolfgang Bumiller]

applied this patch

On Mon, Jul 27, 2020 at 08:54:48AM +0200, Dominik Csapak wrote:
> 'username' here is without realm, but we really want to use user@realm
> 
> Signed-off-by: Dominik Csapak <d.csapak@proxmox.com>
> ---
>  src/api2/node.rs | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/src/api2/node.rs b/src/api2/node.rs
> index b80a661..e6ecc85 100644
> --- a/src/api2/node.rs
> +++ b/src/api2/node.rs
> @@ -137,7 +137,7 @@ async fn termproxy(
>      let upid = WorkerTask::spawn(
>          "termproxy",
>          None,
> -        &username,
> +        &userid,
>          false,
>          move |worker| async move {
>              // move inside the worker so that it survives and does not close the port
> -- 
> 2.20.1