public inbox for linux-s390@vger.kernel.org
 help / color / mirror / Atom feed
From: Stefan Haberland <sth@linux.ibm.com>
To: Jens Axboe <axboe@kernel.dk>
Cc: linux-block@vger.kernel.org,
	Jan Hoeppner <hoeppner@linux.ibm.com>,
	linux-s390@vger.kernel.org, Heiko Carstens <hca@linux.ibm.com>,
	Vasily Gorbik <gor@linux.ibm.com>,
	Christian Borntraeger <borntraeger@de.ibm.com>
Subject: [PATCH 4/4] s390/dasd: Use scnprintf() instead of sprintf()
Date: Wed, 26 Nov 2025 17:06:34 +0100	[thread overview]
Message-ID: <20251126160634.3446919-5-sth@linux.ibm.com> (raw)
In-Reply-To: <20251126160634.3446919-1-sth@linux.ibm.com>

From: Jan Höppner <hoeppner@linux.ibm.com>

Use scnprintf() instead of sprintf() for those cases where the
destination is an array and the size of the array is known at compile
time.

This prevents theoretical buffer overflows, but also avoids that people
again and again spend time to figure out if the code is actually safe.

Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
Reviewed-by: Stefan Haberland <sth@linux.ibm.com>
Signed-off-by: Stefan Haberland <sth@linux.ibm.com>
---
 drivers/s390/block/dasd_devmap.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c
index ddbdf1f85d44..73972900fc55 100644
--- a/drivers/s390/block/dasd_devmap.c
+++ b/drivers/s390/block/dasd_devmap.c
@@ -355,7 +355,8 @@ static int __init dasd_parse_range(const char *range)
 	/* each device in dasd= parameter should be set initially online */
 	features |= DASD_FEATURE_INITIAL_ONLINE;
 	while (from <= to) {
-		sprintf(bus_id, "%01x.%01x.%04x", from_id0, from_id1, from++);
+		scnprintf(bus_id, sizeof(bus_id),
+			  "%01x.%01x.%04x", from_id0, from_id1, from++);
 		devmap = dasd_add_busid(bus_id, features);
 		if (IS_ERR(devmap)) {
 			rc = PTR_ERR(devmap);
-- 
2.51.0


  parent reply	other threads:[~2025-11-26 16:06 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-11-26 16:06 [PATCH 0/4] s390/dasd: Minor cleanups and copy-pair swap fix Stefan Haberland
2025-11-26 16:06 ` [PATCH 1/4] s390/dasd: Fix gendisk parent after copy pair swap Stefan Haberland
2025-11-26 16:06 ` [PATCH 2/4] s390/dasd: Remove unnecessary debugfs_create() return checks Stefan Haberland
2025-11-26 16:06 ` [PATCH 3/4] s390/dasd: Move device name formatting into separate function Stefan Haberland
2025-11-26 16:06 ` Stefan Haberland [this message]
2025-11-26 17:14 ` [PATCH 0/4] s390/dasd: Minor cleanups and copy-pair swap fix Jens Axboe

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20251126160634.3446919-5-sth@linux.ibm.com \
    --to=sth@linux.ibm.com \
    --cc=axboe@kernel.dk \
    --cc=borntraeger@de.ibm.com \
    --cc=gor@linux.ibm.com \
    --cc=hca@linux.ibm.com \
    --cc=hoeppner@linux.ibm.com \
    --cc=linux-block@vger.kernel.org \
    --cc=linux-s390@vger.kernel.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox