linux-kernel - [PATCH 06/10] of/fdt: Fix the len check in early_init_dt_check_for

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20251112143520.233870-7-yuntao.wang@linux.dev>
Date: Wed, 12 Nov 2025 22:35:16 +0800
From: Yuntao Wang <yuntao.wang@...ux.dev>
To: Rob Herring <robh@...nel.org>,
	Saravana Kannan <saravanak@...gle.com>
Cc: Geert Uytterhoeven <geert+renesas@...der.be>,
	Catalin Marinas <catalin.marinas@....com>,
	AKASHI Takahiro <takahiro.akashi@...aro.org>,
	James Morse <james.morse@....com>,
	Chen Zhou <chenzhou10@...wei.com>,
	Baoquan He <bhe@...hat.com>,
	Zhen Lei <thunder.leizhen@...wei.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Changyuan Lyu <changyuanl@...gle.com>,
	Alexander Graf <graf@...zon.com>,
	"Mike Rapoport (Microsoft)" <rppt@...nel.org>,
	devicetree@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Yuntao Wang <yuntao.wang@...ux.dev>
Subject: [PATCH 06/10] of/fdt: Fix the len check in early_init_dt_check_for_elfcorehdr()

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")
Fixes: e62aaeac426ab1dd ("arm64: kdump: provide /proc/vmcore file")
Reviewed-by: Geert Uytterhoeven <geert+renesas@...der.be>
Signed-off-by: Yuntao Wang <yuntao.wang@...ux.dev>
---
 drivers/of/fdt.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index a1db3c9ac981..716ebe8c23d3 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -821,7 +821,7 @@ 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 < dt_root_addr_size_bytes())
 		return;
 
 	elfcorehdr_addr = dt_mem_next_cell(dt_root_addr_cells, &prop);
-- 
2.51.0