2020-12-17 17:38:29

by Lakshmi Ramasubramanian

Subject: [PATCH v12 3/4] arm64: Free DTB buffer if fdt_open_into() fails

create_dtb() function allocates memory for the device tree blob (DTB)
and calls fdt_open_into(). If this call fails the memory allocated
for the DTB is not freed before returning from create_dtb() thereby
leaking memory.

Call vfree() to free the memory allocated for the DTB if fdt_open_into()
fails.

Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
---
arch/arm64/kernel/machine_kexec_file.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
index 7de9c47dee7c..3e045cd62451 100644
--- a/arch/arm64/kernel/machine_kexec_file.c
+++ b/arch/arm64/kernel/machine_kexec_file.c
@@ -65,8 +65,10 @@ static int create_dtb(struct kimage *image,

/* duplicate a device tree blob */
ret = fdt_open_into(initial_boot_params, buf, buf_size);
- if (ret)
+ if (ret) {
+ vfree(buf);
return -EINVAL;
+ }

ret = of_kexec_setup_new_fdt(image, buf, initrd_load_addr,
initrd_len, cmdline);
--
2.29.2

2020-12-17 18:33:17

by Lakshmi Ramasubramanian

Subject: Re: [PATCH v12 3/4] arm64: Free DTB buffer if fdt_open_into() fails

On 12/17/20 9:37 AM, Lakshmi Ramasubramanian wrote:
> create_dtb() function allocates memory for the device tree blob (DTB)
> and calls fdt_open_into(). If this call fails the memory allocated
> for the DTB is not freed before returning from create_dtb() thereby
> leaking memory.

Typo in the email address of James Morse (ARM.com). Sorry about that.
Adding the correct email address.

-lakshmi

>
> Call vfree() to free the memory allocated for the DTB if fdt_open_into()
> fails.
>
> Signed-off-by: Lakshmi Ramasubramanian <[email protected]>
> ---
> arch/arm64/kernel/machine_kexec_file.c | 4 +++-
> 1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/arch/arm64/kernel/machine_kexec_file.c b/arch/arm64/kernel/machine_kexec_file.c
> index 7de9c47dee7c..3e045cd62451 100644
> --- a/arch/arm64/kernel/machine_kexec_file.c
> +++ b/arch/arm64/kernel/machine_kexec_file.c
> @@ -65,8 +65,10 @@ static int create_dtb(struct kimage *image,
>
> /* duplicate a device tree blob */
> ret = fdt_open_into(initial_boot_params, buf, buf_size);
> - if (ret)
> + if (ret) {
> + vfree(buf);
> return -EINVAL;
> + }
>
> ret = of_kexec_setup_new_fdt(image, buf, initrd_load_addr,
> initrd_len, cmdline);
>