[PATCH] fdt: Update CRC check for rng-seed

[PATCH] fdt: Update CRC check for rng-seed

[Hsin-Yi Wang]

Commit 428826f5358c ("fdt: add support for rng-seed") moves of_fdt_crc32
from early_init_dt_verify() to early_init_dt_scan() since
early_init_dt_scan_chosen() may modify fdt to erase rng-seed.

However, arm and some other arch won't call early_init_dt_scan(), they
call early_init_dt_verify() then early_init_dt_scan_nodes().

Restore of_fdt_crc32 to early_init_dt_verify() then update it in
early_init_dt_scan_chosen() if fdt if updated.

Fixes: 428826f5358c ("fdt: add support for rng-seed")
Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
---
 drivers/of/fdt.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
index 7d97ab6d0e31..223d617ecfe1 100644
--- a/drivers/of/fdt.c
+++ b/drivers/of/fdt.c
@@ -1086,6 +1086,10 @@ int __init early_init_dt_scan_chosen(unsigned long node, const char *uname,
 
 		/* try to clear seed so it won't be found. */
 		fdt_nop_property(initial_boot_params, node, "rng-seed");
+
+		/* update CRC check value */
+		of_fdt_crc32 = crc32_be(~0, initial_boot_params,
+				fdt_totalsize(initial_boot_params));
 	}
 
 	/* break now */
@@ -1176,6 +1180,8 @@ bool __init early_init_dt_verify(void *params)
 
 	/* Setup flat device-tree pointer */
 	initial_boot_params = params;
+	of_fdt_crc32 = crc32_be(~0, initial_boot_params,
+				fdt_totalsize(initial_boot_params));
 	return true;
 }
 
@@ -1205,8 +1211,6 @@ bool __init early_init_dt_scan(void *params)
 		return false;
 
 	early_init_dt_scan_nodes();
-	of_fdt_crc32 = crc32_be(~0, initial_boot_params,
-				fdt_totalsize(initial_boot_params));
 	return true;
 }
 
-- 
2.20.1


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH] fdt: Update CRC check for rng-seed

[Geert Uytterhoeven]

Hi Hsin-Yi,

Thanks for the prompt fix!

On Tue, Aug 27, 2019 at 12:34 PM Hsin-Yi Wang <hsinyi@chromium.org> wrote:
> Commit 428826f5358c ("fdt: add support for rng-seed") moves of_fdt_crc32
> from early_init_dt_verify() to early_init_dt_scan() since
> early_init_dt_scan_chosen() may modify fdt to erase rng-seed.
>
> However, arm and some other arch won't call early_init_dt_scan(), they
> call early_init_dt_verify() then early_init_dt_scan_nodes().
>
> Restore of_fdt_crc32 to early_init_dt_verify() then update it in
> early_init_dt_scan_chosen() if fdt if updated.
>
> Fixes: 428826f5358c ("fdt: add support for rng-seed")

Reported-by: Geert Uytterhoeven <geert+renesas@glider.be>

> Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>

Tested-by: Geert Uytterhoeven <geert+renesas@glider.be>

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

Re: [PATCH] fdt: Update CRC check for rng-seed

[Will Deacon]

On Tue, Aug 27, 2019 at 06:33:53PM +0800, Hsin-Yi Wang wrote:
> Commit 428826f5358c ("fdt: add support for rng-seed") moves of_fdt_crc32
> from early_init_dt_verify() to early_init_dt_scan() since
> early_init_dt_scan_chosen() may modify fdt to erase rng-seed.
> 
> However, arm and some other arch won't call early_init_dt_scan(), they
> call early_init_dt_verify() then early_init_dt_scan_nodes().
> 
> Restore of_fdt_crc32 to early_init_dt_verify() then update it in
> early_init_dt_scan_chosen() if fdt if updated.
> 
> Fixes: 428826f5358c ("fdt: add support for rng-seed")
> Signed-off-by: Hsin-Yi Wang <hsinyi@chromium.org>
> ---
>  drivers/of/fdt.c | 8 ++++++--
>  1 file changed, 6 insertions(+), 2 deletions(-)

Thanks, I'll queue this up with the tags from Geert.

Will

_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel