diff mbox series

[2/3] tracing/probes: Fix to exit fetching if an error is detected

Message ID 168830924625.2278819.7022958622963157629.stgit@mhiramat.roam.corp.google.com
State New
Headers
Series tracing/probes: Fix bugs in process_fetch_insn |

Commit Message

Masami Hiramatsu (Google) July 2, 2023, 2:47 p.m. UTC 
  From: Masami Hiramatsu (Google) <mhiramat@kernel.org>

Fix to exit fetching arguments if an error is detected when storing
strings. Without this fix, if an array is specified with string types
it may store the data at the wrong address.

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Closes: https://lore.kernel.org/all/8819b154-2ba1-43c3-98a2-cbde20892023@moroto.mountain/
Fixes: 9b960a38835f ("tracing: probeevent: Unify fetch_insn processing common part")
Cc: stable@vger.kernel.org
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
---
 kernel/trace/trace_probe_tmpl.h |    2 ++
 1 file changed, 2 insertions(+)

Comments

Masami Hiramatsu (Google) July 7, 2023, 7:07 a.m. UTC | #1 
On Sun,  2 Jul 2023 23:47:26 +0900
"Masami Hiramatsu (Google)" <mhiramat@kernel.org> wrote:

> From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> 
> Fix to exit fetching arguments if an error is detected when storing
> strings. Without this fix, if an array is specified with string types
> it may store the data at the wrong address.
> 
> Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
> Closes: https://lore.kernel.org/all/8819b154-2ba1-43c3-98a2-cbde20892023@moroto.mountain/
> Fixes: 9b960a38835f ("tracing: probeevent: Unify fetch_insn processing common part")
> Cc: stable@vger.kernel.org
> Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
> Reviewed-by: Steven Rostedt (Google) <rostedt@goodmis.org>
> ---
>  kernel/trace/trace_probe_tmpl.h |    2 ++
>  1 file changed, 2 insertions(+)
> 
> diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h
> index 4735c5cb76fa..d6f2bf69f9bc 100644
> --- a/kernel/trace/trace_probe_tmpl.h
> +++ b/kernel/trace/trace_probe_tmpl.h
> @@ -193,6 +193,8 @@ process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val,
>  	default:
>  		return -EILSEQ;
>  	}
> +	if (ret < 0)
> +		return ret;

I found this will leave a garbage data on the trace data if we are in the array.
Let me fix this issue.
(-EILSEQ case has another issue. I think it should not be recorded)

Thank you,

>  	code++;
>  
>  	/* 4th stage: modify stored value if needed */
>
diff mbox series

Patch

diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h
index 4735c5cb76fa..d6f2bf69f9bc 100644
--- a/kernel/trace/trace_probe_tmpl.h
+++ b/kernel/trace/trace_probe_tmpl.h
@@ -193,6 +193,8 @@  process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val,
 	default:
 		return -EILSEQ;
 	}
+	if (ret < 0)
+		return ret;
 	code++;
 
 	/* 4th stage: modify stored value if needed */