Re: [PATCH] linux/ofpath: Add missing strdup failure checks

[Avnish Chouhan <avnish@linux.ibm.com>]

On 2025-11-18 22:31, grub-devel-request@gnu.org wrote:
> Message: 2
> Date: Tue, 18 Nov 2025 19:55:39 +0530
> From: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
> To: grub-devel@gnu.org
> Cc: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>, ssrish@linux.ibm.com,
> 	sridharm@linux.ibm.com, stefanb@linux.ibm.com
> Subject: [PATCH] linux/ofpath: Add missing strdup failure checks
> Message-ID: <20251118142539.38467-1-sudhakar@linux.ibm.com>
> 
> Segmentation faults or undefined behaviour may result from a null 
> pointer
> dereference in strip_trailing_digits and grub_util_devname_to_ofpath if
> strdup() fails. Therefore, I added a NULL check to fix this.
> 
> Signed-off-by: Sudhakar Kuppusamy <sudhakar@linux.ibm.com>
> ---
>  grub-core/osdep/linux/ofpath.c | 11 +++++++++++
>  1 file changed, 11 insertions(+)
> 
> diff --git a/grub-core/osdep/linux/ofpath.c 
> b/grub-core/osdep/linux/ofpath.c
> index a6153d359..ade5220db 100644
> --- a/grub-core/osdep/linux/ofpath.c
> +++ b/grub-core/osdep/linux/ofpath.c
> @@ -695,6 +695,9 @@ strip_trailing_digits (const char *p)
>    char *new, *end;
> 
>    new = strdup (p);
> +  if (new == NULL)
> +    return NULL;
> +
>    end = new + strlen(new) - 1;
>    while (end >= new)
>      {
> @@ -715,7 +718,15 @@ grub_util_devname_to_ofpath (const char 
> *sys_devname)
> 
>    device = get_basename (name_buf);
>    devnode = strip_trailing_digits (name_buf);
> +  if (devnode == NULL)

Hi Sudhakar,

This change will lead to a memory leak. You need to add "free 
(name_buf);" here before retuning!

> +    return NULL;
> +
>    devicenode = strip_trailing_digits (device);
> +  if (devicenode == NULL)
> +    {
> +      free (devnode);

And here too, "free (name_buf);"......

Thank you!

Regards,
Avnish Chouhan

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