[PATCH 08/11] blktrace: convert strncpy() to strscpy_pad()

Arnd Bergmann
2024-03-28T14:06:54Z

From: Arnd Bergmann <arnd@arndb.de>

gcc-9 warns about a possibly non-terminated string copy:

kernel/trace/blktrace.c: In function 'do_blk_trace_setup':
kernel/trace/blktrace.c:527:2: error: 'strncpy' specified bound 32 equals destination size [-Werror=stringop-truncation]

Newer versions are fine here because they see the following explicit
nul-termination. Using strscpy_pad() avoids the warning and
simplifies the code a little. The padding helps give a clean
buffer to userspace.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
kernel/trace/blktrace.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index d5d94510afd3..95a00160d465 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -524,8 +524,7 @@ static int do_blk_trace_setup(struct request_queue *q, char *name, dev_t dev,
if (!buts->buf_size || !buts->buf_nr)
return -EINVAL;

- strncpy(buts->name, name, BLKTRACE_BDEV_SIZE);
- buts->name[BLKTRACE_BDEV_SIZE - 1] = '\0';
+ strscpy(buts->name, name, BLKTRACE_BDEV_SIZE);

/*
* some device names have larger paths - convert the slashes
--
2.39.2