[PATCH master 1/2] ARM: cpu: start: align uncompressed DTB size to 4 bytes

[PATCH master 1/2] ARM: cpu: start: align uncompressed DTB size to 4 bytes

[Ahmad Fatoum]

KASAN reports that decompression exceeds the bounds of the allocation
and my DT size isn't 4-bytes aligned. Align the allocation size to fix
this.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 arch/arm/cpu/start.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/arm/cpu/start.c b/arch/arm/cpu/start.c
index 6d0a7cfc6b04..2adc60fa8831 100644
--- a/arch/arm/cpu/start.c
+++ b/arch/arm/cpu/start.c
@@ -79,7 +79,7 @@ void *barebox_arm_boot_dtb(void)
 
 	pr_debug("%s: using compressed_dtb\n", __func__);
 
-	dtb = malloc(compressed_dtb->datalen_uncompressed);
+	dtb = malloc(ALIGN(compressed_dtb->datalen_uncompressed, 4));
 	if (!dtb)
 		return NULL;
 
-- 
2.39.2

[PATCH master 2/2] RISC-V: start: align uncompressed DTB size to 4 bytes

[Ahmad Fatoum]

On ARM, I ran into a KASAN splat, because the uncompressed DT may not
have a 4-byte aligned size. This can affect RISC-V boards too, so import
the fix done there.

Signed-off-by: Ahmad Fatoum <a.fatoum@pengutronix.de>
---
 arch/riscv/boot/start.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/boot/start.c b/arch/riscv/boot/start.c
index 92991d0f6a84..d20526293bac 100644
--- a/arch/riscv/boot/start.c
+++ b/arch/riscv/boot/start.c
@@ -54,7 +54,7 @@ void *barebox_riscv_boot_dtb(void)
 
 	pr_debug("%s: using compressed_dtb\n", __func__);
 
-	dtb = malloc(compressed_dtb->datalen_uncompressed);
+	dtb = malloc(ALIGN(compressed_dtb->datalen_uncompressed, 4));
 	if (!dtb)
 		return NULL;
 
-- 
2.39.2

Re: [PATCH master 1/2] ARM: cpu: start: align uncompressed DTB size to 4 bytes

[Sascha Hauer]

On Fri, 17 May 2024 08:22:24 +0200, Ahmad Fatoum wrote:
> KASAN reports that decompression exceeds the bounds of the allocation
> and my DT size isn't 4-bytes aligned. Align the allocation size to fix
> this.
> 
> 

Applied, thanks!

[1/2] ARM: cpu: start: align uncompressed DTB size to 4 bytes
      https://git.pengutronix.de/cgit/barebox/commit/?id=ce38eef3c056 (link may not be stable)
[2/2] RISC-V: start: align uncompressed DTB size to 4 bytes
      https://git.pengutronix.de/cgit/barebox/commit/?id=249164bc555f (link may not be stable)

Best regards,
-- 
Sascha Hauer <s.hauer@pengutronix.de>