Linux-ARM-Kernel Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: hanzhijian <hanzhijian1991@gmail.com>
To: Daniel Palmer <daniel@thingy.jp>,
	Romain Perier <romain.perier@gmail.com>,
	Michael Turquette <mturquette@baylibre.com>,
	Stephen Boyd <sboyd@kernel.org>
Cc: Brian Masney <bmasney@redhat.com>,
	linux-arm-kernel@lists.infradead.org, linux-clk@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	hanzhijian <hanzhijian1991@gmail.com>
Subject: [PATCH] clk: mstar: msc313-mpll: fix off-by-one in clock array allocation
Date: Sat, 22 Aug 2026 07:58:37 +0800	[thread overview]
Message-ID: <20260821235837.2341179-1-hanzhijian1991@gmail.com> (raw)

The hws array of mpll->clk_data is allocated with struct_size() using
ARRAY_SIZE(output_dividers) as the element count, giving it 7 elements.
But the probe function stores the MPLL clock at hws[0] and one
fixed-factor clock for each output divider at hws[i + 1] for i in
[0, ARRAY_SIZE(output_dividers)), writing 8 elements in total.  The
final write to hws[7] is past the end of the allocation.

clk_data->num is also set to NUMOUTPUTS (8), so the clock framework
reads hws[0..7], again accessing hws[7] out of bounds.

Use NUMOUTPUTS as the element count so the allocation matches the
number of clocks actually stored and exposed.

Found by smatch:
  drivers/clk/mstar/clk-msc313-mpll.c:134 msc313_mpll_probe()
  error: buffer overflow 'mpll->clk_data->hws' 7 <= 7

Signed-off-by: hanzhijian <hanzhijian1991@gmail.com>
---
 drivers/clk/mstar/clk-msc313-mpll.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/clk/mstar/clk-msc313-mpll.c b/drivers/clk/mstar/clk-msc313-mpll.c
index 61beb4e87..bd45aa0ae 100644
--- a/drivers/clk/mstar/clk-msc313-mpll.c
+++ b/drivers/clk/mstar/clk-msc313-mpll.c
@@ -105,7 +105,7 @@ static int msc313_mpll_probe(struct platform_device *pdev)
 		return PTR_ERR(mpll->loop_div_second);
 
 	mpll->clk_data = devm_kzalloc(dev, struct_size(mpll->clk_data, hws,
-			ARRAY_SIZE(output_dividers)), GFP_KERNEL);
+				NUMOUTPUTS), GFP_KERNEL);
 	if (!mpll->clk_data)
 		return -ENOMEM;
 
-- 
2.43.0



             reply	other threads:[~2026-08-21 23:59 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-08-21 23:58 hanzhijian [this message]
2026-08-24 11:30 ` [PATCH] clk: mstar: msc313-mpll: fix off-by-one in clock array allocation Markus Elfring
2026-08-24 14:28   ` [PATCH v2] " hanzhijian
2026-08-24 16:00     ` Brian Masney

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=20260821235837.2341179-1-hanzhijian1991@gmail.com \
    --to=hanzhijian1991@gmail.com \
    --cc=bmasney@redhat.com \
    --cc=daniel@thingy.jp \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-clk@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mturquette@baylibre.com \
    --cc=romain.perier@gmail.com \
    --cc=sboyd@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