Re: [PATCH 1/1] riscv: add NULL check before calling strlen in the riscv cpu's get_desc()

[Leo Liang]

On Mon, May 06, 2024 at 05:10:06PM +0800, Hanyuan Zhao wrote:
> Without the NULL check, if the devicetree that u-boot loads does not have a
> compatible property then a store access fault will be raised and force the
> machine to reset, due to the NULL pointer we passed to strlen. This commit
> adds this check and will return -ENOSPC to indicate the get_desc failed.
> 
> Signed-off-by: Hanyuan Zhao 
> ---
>  drivers/cpu/riscv_cpu.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)

Reviewed-by: Leo Yu-Chi Liang 

[PATCH 1/1] riscv: add NULL check before calling strlen in the riscv cpu's get_desc()

[Hanyuan Zhao]

Without the NULL check, if the devicetree that u-boot loads does not have a
compatible property then a store access fault will be raised and force the
machine to reset, due to the NULL pointer we passed to strlen. This commit
adds this check and will return -ENOSPC to indicate the get_desc failed.

Signed-off-by: Hanyuan Zhao 
---
 drivers/cpu/riscv_cpu.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/cpu/riscv_cpu.c b/drivers/cpu/riscv_cpu.c
index 9b1950efe0..d39a943cb8 100644
--- a/drivers/cpu/riscv_cpu.c
+++ b/drivers/cpu/riscv_cpu.c
@@ -24,7 +24,7 @@ static int riscv_cpu_get_desc(const struct udevice *dev, char 
*buf, int size)
const char *cpu;
 
cpu = dev_read_string(dev, "compatible");
-   if (size < (strlen(cpu) + 1))
+   if (!cpu || size < (strlen(cpu) + 1))
return -ENOSPC;
 
strcpy(buf, cpu);
-- 
2.34.1