devicetree.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Yuntao Wang <yuntao.wang@linux.dev>
To: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org
Cc: Rob Herring <robh@kernel.org>,
	Saravana Kannan <saravanak@google.com>,
	Geert Uytterhoeven <geert+renesas@glider.be>,
	Yuntao Wang <yuntao.wang@linux.dev>
Subject: [PATCH] of: fdt: Fix the len check in early_init_dt_check_for_elfcorehdr()
Date: Sun,  2 Nov 2025 22:17:33 +0800	[thread overview]
Message-ID: <20251102141733.160640-1-yuntao.wang@linux.dev> (raw)

The len value is in bytes, while `dt_root_addr_cells + dt_root_size_cells`
is in cells (4 bytes per cell).

Comparing them directly is incorrect. Convert units before comparison.

Fixes: f7e7ce93aac1 ("of: fdt: Add generic support for handling elf core headers property")
Signed-off-by: Yuntao Wang <yuntao.wang@linux.dev>
---
 drivers/of/fdt.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 0edd639898a6..f79461f5cffc 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -812,6 +812,7 @@ static void __init early_init_dt_check_for_initrd(unsigned long node)
  */
 static void __init early_init_dt_check_for_elfcorehdr(unsigned long node)
 {
+	int t_len = (dt_root_addr_cells + dt_root_size_cells) * sizeof(__be32);
 	const __be32 *prop;
 	int len;
 
@@ -821,7 +822,7 @@ static void __init early_init_dt_check_for_elfcorehdr(unsigned long node)
 	pr_debug("Looking for elfcorehdr property... ");
 
 	prop = of_get_flat_dt_prop(node, "linux,elfcorehdr", &len);
-	if (!prop || (len < (dt_root_addr_cells + dt_root_size_cells)))
+	if (!prop || len < t_len)
 		return;
 
 	elfcorehdr_addr = dt_mem_next_cell(dt_root_addr_cells, &prop);
-- 
2.51.0


             reply	other threads:[~2025-11-02 14:18 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2025-11-02 14:17 Yuntao Wang [this message]
2025-11-03 14:51 ` [PATCH] of: fdt: Fix the len check in early_init_dt_check_for_elfcorehdr() Geert Uytterhoeven
2025-11-05  9:00   ` [PATCH v2] " Yuntao Wang
2025-11-11 16:56     ` Rob Herring
2025-11-12 14:58       ` Yuntao Wang

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=20251102141733.160640-1-yuntao.wang@linux.dev \
    --to=yuntao.wang@linux.dev \
    --cc=devicetree@vger.kernel.org \
    --cc=geert+renesas@glider.be \
    --cc=linux-kernel@vger.kernel.org \
    --cc=robh@kernel.org \
    --cc=saravanak@google.com \
    /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;
as well as URLs for NNTP newsgroup(s).