[PATCH 5.14 314/849] tools/latency-collector: Use correct size when writing queue_full_warning

From: Greg Kroah-Hartman
Date: Mon Nov 15 2021 - 20:38:19 EST


From: Viktor Rosendahl <Viktor.Rosendahl@xxxxxx>

[ Upstream commit f604de20c0a47e0e9518940a1810193678c92fa8 ]

queue_full_warning is a pointer, so it is wrong to use sizeof to calculate
the number of characters of the string it points to. The effect is that we
only print out the first few characters of the warning string.

The correct way is to use strlen(). We don't need to add 1 to the strlen()
because we don't want to write the terminating null character to stdout.

Link: https://lkml.kernel.org/r/20211019160701.15587-1-Viktor.Rosendahl@xxxxxx

Link: https://lore.kernel.org/r/8fd4bb65ef3da67feac9ce3258cdbe9824752cf1.1629198502.git.jing.yangyang@xxxxxxxxxx
Link: https://lore.kernel.org/r/20211012025424.180781-1-davidcomponentone@xxxxxxxxx
Reported-by: Zeal Robot <zealci@xxxxxxxxxx>
Signed-off-by: Viktor Rosendahl <Viktor.Rosendahl@xxxxxx>
Signed-off-by: Steven Rostedt (VMware) <rostedt@xxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
tools/tracing/latency/latency-collector.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/tools/tracing/latency/latency-collector.c b/tools/tracing/latency/latency-collector.c
index 3a2e6bb781a8c..59a7f2346eab4 100644
--- a/tools/tracing/latency/latency-collector.c
+++ b/tools/tracing/latency/latency-collector.c
@@ -1538,7 +1538,7 @@ static void tracing_loop(void)
mutex_lock(&print_mtx);
check_signals();
write_or_die(fd_stdout, queue_full_warning,
- sizeof(queue_full_warning));
+ strlen(queue_full_warning));
mutex_unlock(&print_mtx);
}
modified--;
--
2.33.0