[PATCH] SUNRPC: Fix rpcgss_context trace event acceptor field

[PATCH] SUNRPC: Fix rpcgss_context trace event acceptor field

[Steven Rostedt]

From: "Steven Rostedt (Google)" <rostedt@goodmis.org>

The rpcgss_context trace event acceptor field is a dynamically sized
string that records the "data" parameter. But this parameter is also
dependent on the "len" field to determine the size of the data.

It needs to use __string_len() helper macro where the length can be passed
in. It also incorrectly uses strncpy() to save it instead of
__assign_str(). As these macros can change, it is not wise to open code
them in trace events.

As of commit c759e609030c ("tracing: Remove __assign_str_len()"),
__assign_str() can be used for both __string() and __string_len() fields.
Before that commit, __assign_str_len() is required to be used. This needs
to be noted for backporting. (In actuality, commit c1fa617caeb0 ("tracing:
Rework __assign_str() and __string() to not duplicate getting the string")
is the commit that makes __string_str_len() obsolete).

Cc: stable@vger.kernel.org
Fixes: 0c77668ddb4e7 ("SUNRPC: Introduce trace points in rpc_auth_gss.ko")
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
 include/trace/events/rpcgss.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/include/trace/events/rpcgss.h b/include/trace/events/rpcgss.h
index ba2d96a1bc2f..f50fcafc69de 100644
--- a/include/trace/events/rpcgss.h
+++ b/include/trace/events/rpcgss.h
@@ -609,7 +609,7 @@ TRACE_EVENT(rpcgss_context,
 		__field(unsigned int, timeout)
 		__field(u32, window_size)
 		__field(int, len)
-		__string(acceptor, data)
+		__string_len(acceptor, data, len)
 	),
 
 	TP_fast_assign(
@@ -618,7 +618,7 @@ TRACE_EVENT(rpcgss_context,
 		__entry->timeout = timeout;
 		__entry->window_size = window_size;
 		__entry->len = len;
-		strncpy(__get_str(acceptor), data, len);
+		__assign_str(acceptor, data);
 	),
 
 	TP_printk("win_size=%u expiry=%lu now=%lu timeout=%u acceptor=%.*s",
-- 
2.43.0

Re: [PATCH] SUNRPC: Fix rpcgss_context trace event acceptor field

[Chuck Lever]

On Wed, Apr 10, 2024 at 12:38:13PM -0400, Steven Rostedt wrote:
> From: "Steven Rostedt (Google)" <rostedt@goodmis.org>
> 
> The rpcgss_context trace event acceptor field is a dynamically sized
> string that records the "data" parameter. But this parameter is also
> dependent on the "len" field to determine the size of the data.
> 
> It needs to use __string_len() helper macro where the length can be passed
> in. It also incorrectly uses strncpy() to save it instead of
> __assign_str(). As these macros can change, it is not wise to open code
> them in trace events.
> 
> As of commit c759e609030c ("tracing: Remove __assign_str_len()"),
> __assign_str() can be used for both __string() and __string_len() fields.
> Before that commit, __assign_str_len() is required to be used. This needs
> to be noted for backporting. (In actuality, commit c1fa617caeb0 ("tracing:
> Rework __assign_str() and __string() to not duplicate getting the string")
> is the commit that makes __string_str_len() obsolete).
> 
> Cc: stable@vger.kernel.org
> Fixes: 0c77668ddb4e7 ("SUNRPC: Introduce trace points in rpc_auth_gss.ko")
> Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>

Acked-by: Chuck Lever <chuck.lever@oracle.com>


> ---
>  include/trace/events/rpcgss.h | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/include/trace/events/rpcgss.h b/include/trace/events/rpcgss.h
> index ba2d96a1bc2f..f50fcafc69de 100644
> --- a/include/trace/events/rpcgss.h
> +++ b/include/trace/events/rpcgss.h
> @@ -609,7 +609,7 @@ TRACE_EVENT(rpcgss_context,
>  		__field(unsigned int, timeout)
>  		__field(u32, window_size)
>  		__field(int, len)
> -		__string(acceptor, data)
> +		__string_len(acceptor, data, len)
>  	),
>  
>  	TP_fast_assign(
> @@ -618,7 +618,7 @@ TRACE_EVENT(rpcgss_context,
>  		__entry->timeout = timeout;
>  		__entry->window_size = window_size;
>  		__entry->len = len;
> -		strncpy(__get_str(acceptor), data, len);
> +		__assign_str(acceptor, data);
>  	),
>  
>  	TP_printk("win_size=%u expiry=%lu now=%lu timeout=%u acceptor=%.*s",
> -- 
> 2.43.0
> 

-- 
Chuck Lever

Re: [PATCH] SUNRPC: Fix rpcgss_context trace event acceptor field

[Steven Rostedt]

On Wed, 10 Apr 2024 12:38:53 -0400
Chuck Lever <chuck.lever@oracle.com> wrote:

> On Wed, Apr 10, 2024 at 12:38:13PM -0400, Steven Rostedt wrote:
> > From: "Steven Rostedt (Google)" <rostedt@goodmis.org>
> > 
> > The rpcgss_context trace event acceptor field is a dynamically sized
> > string that records the "data" parameter. But this parameter is also
> > dependent on the "len" field to determine the size of the data.
> > 
> > It needs to use __string_len() helper macro where the length can be passed
> > in. It also incorrectly uses strncpy() to save it instead of
> > __assign_str(). As these macros can change, it is not wise to open code
> > them in trace events.
> > 
> > As of commit c759e609030c ("tracing: Remove __assign_str_len()"),
> > __assign_str() can be used for both __string() and __string_len() fields.
> > Before that commit, __assign_str_len() is required to be used. This needs
> > to be noted for backporting. (In actuality, commit c1fa617caeb0 ("tracing:
> > Rework __assign_str() and __string() to not duplicate getting the string")
> > is the commit that makes __string_str_len() obsolete).
> > 
> > Cc: stable@vger.kernel.org
> > Fixes: 0c77668ddb4e7 ("SUNRPC: Introduce trace points in rpc_auth_gss.ko")
> > Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>  
> 
> Acked-by: Chuck Lever <chuck.lever@oracle.com>
> 

Thanks, but feel free to take it if you want. Unless you rather have me
take it through my tree?

-- Steve

Re: [PATCH] SUNRPC: Fix rpcgss_context trace event acceptor field

[Chuck Lever]

On Wed, Apr 10, 2024 at 01:07:41PM -0400, Steven Rostedt wrote:
> On Wed, 10 Apr 2024 12:38:53 -0400
> Chuck Lever <chuck.lever@oracle.com> wrote:
> 
> > On Wed, Apr 10, 2024 at 12:38:13PM -0400, Steven Rostedt wrote:
> > > From: "Steven Rostedt (Google)" <rostedt@goodmis.org>
> > > 
> > > The rpcgss_context trace event acceptor field is a dynamically sized
> > > string that records the "data" parameter. But this parameter is also
> > > dependent on the "len" field to determine the size of the data.
> > > 
> > > It needs to use __string_len() helper macro where the length can be passed
> > > in. It also incorrectly uses strncpy() to save it instead of
> > > __assign_str(). As these macros can change, it is not wise to open code
> > > them in trace events.
> > > 
> > > As of commit c759e609030c ("tracing: Remove __assign_str_len()"),
> > > __assign_str() can be used for both __string() and __string_len() fields.
> > > Before that commit, __assign_str_len() is required to be used. This needs
> > > to be noted for backporting. (In actuality, commit c1fa617caeb0 ("tracing:
> > > Rework __assign_str() and __string() to not duplicate getting the string")
> > > is the commit that makes __string_str_len() obsolete).
> > > 
> > > Cc: stable@vger.kernel.org
> > > Fixes: 0c77668ddb4e7 ("SUNRPC: Introduce trace points in rpc_auth_gss.ko")
> > > Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>  
> > 
> > Acked-by: Chuck Lever <chuck.lever@oracle.com>
> > 
> 
> Thanks, but feel free to take it if you want. Unless you rather have me
> take it through my tree?

Well I guess I could test it for you. I'll take it for nfsd v6.9-rc.


-- 
Chuck Lever

Re: [PATCH] SUNRPC: Fix rpcgss_context trace event acceptor field

[Steven Rostedt]

On Wed, 10 Apr 2024 13:07:20 -0400
Chuck Lever <chuck.lever@oracle.com> wrote:

> Well I guess I could test it for you. I'll take it for nfsd v6.9-rc.

Thanks!

-- Steve