[PATCH] tracing: Always use memcpy() in histogram add_to_key()
From: Steven Rostedt
Date: Thu Apr 03 2025 - 21:05:44 EST
From: Steven Rostedt <rostedt@xxxxxxxxxxx>
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.
Signed-off-by: Steven Rostedt (Google) <rostedt@xxxxxxxxxxx>
---
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 c1ea6aaac182..4258324219ca 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