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From:   Dominique Martinet <asmadeus@codewreck.org>
Cc:     Dominique Martinet <asmadeus@codewreck.org>,
        Jens Axboe <axboe@kernel.dk>,
        Steven Rostedt <rostedt@goodmis.org>,
        Ingo Molnar <mingo@redhat.com>, linux-block@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: =?UTF-8?q?=5BPATCH=2015/18=5D=20blktrace=3A=20change=20strncpy+truncation=20to=20strlcpy?=
Date:   Fri, 13 Jul 2018 03:26:02 +0200
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Using strlcpy fixes this new gcc warning:
    kernel/trace/blktrace.c: In function ‘do_blk_trace_setup’:
    kernel/trace/blktrace.c:497:2: warning: ‘strncpy’ specified bound 32 equals destination size [-Wstringop-truncation]
      strncpy(buts->name, name, BLKTRACE_BDEV_SIZE);
      ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Generated by scripts/coccinelle/misc/strncpy_truncation.cocci

Signed-off-by: Dominique Martinet <asmadeus@codewreck.org>
---

Please see https://marc.info/?l=linux-kernel&m=153144450722324&w=2 (the
first patch of the serie) for the motivation behind this patch

 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 987d9a9ae283..2478d9838eab 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -494,8 +494,7 @@ 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';
+	strlcpy(buts->name, name, BLKTRACE_BDEV_SIZE);
 
 	/*
 	 * some device names have larger paths - convert the slashes
-- 
2.17.1