linux-kernel - [for-next][PATCH 06/31] tracing: Always use memcpy() in histogram add_to

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250509131314.441795527@goodmis.org>
Date: Fri, 09 May 2025 09:12:55 -0400
From: Steven Rostedt <rostedt@...dmis.org>
To: linux-kernel@...r.kernel.org
Cc: Masami Hiramatsu <mhiramat@...nel.org>,
 Mark Rutland <mark.rutland@....com>,
 Mathieu Desnoyers <mathieu.desnoyers@...icios.com>,
 Andrew Morton <akpm@...ux-foundation.org>,
 Kees Cook <keescook@...omium.org>,
 Tom Zanussi <zanussi@...nel.org>
Subject: [for-next][PATCH 06/31] tracing: Always use memcpy() in histogram add_to_key()

From: Steven Rostedt <rostedt@...dmis.org>

The add_to_key() function tests if the key is a string or some data. If
it's a string it does some further calculations of the string size (still
truncating it to the max size it can be), and calls strncpy().

If the key isn't as string it calls memcpy(). The interesting point is
that both use the exact same parameters:

                strncpy(compound_key + key_field->offset, (char *)key, size);
        } else
                memcpy(compound_key + key_field->offset, key, size);

As strncpy() is being used simply as a memcpy() for a string, and since
strncpy() is deprecated, just call memcpy() for both memory and string
keys.

Cc: Mathieu Desnoyers <mathieu.desnoyers@...icios.com>
Cc: Kees Cook <keescook@...omium.org>
Link: https://lore.kernel.org/20250403210637.1c477d4a@gandalf.local.home
Acked-by: Masami Hiramatsu (Google) <mhiramat@...nel.org>
Reviewed-by: Tom Zanussi <zanussi@...nel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@...dmis.org>
---
 kernel/trace/trace_events_hist.c | 6 ++----
 1 file changed, 2 insertions(+), 4 deletions(-)

diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c
index 1260c23cfa5f..e139b58c3a43 100644
--- a/kernel/trace/trace_events_hist.c
+++ b/kernel/trace/trace_events_hist.c
@@ -5224,10 +5224,8 @@ static inline void add_to_key(char *compound_key, void *key,
 		/* ensure NULL-termination */
 		if (size > key_field->size - 1)
 			size = key_field->size - 1;
-
-		strncpy(compound_key + key_field->offset, (char *)key, size);
-	} else
-		memcpy(compound_key + key_field->offset, key, size);
+	}
+	memcpy(compound_key + key_field->offset, key, size);
 }
 
 static void
-- 
2.47.2