Re: [PATCH v2 1/4] misc: fastrpc: Add NULL check to fastrpc_buf_free to prevent crash

[Greg KH]

On Thu, Jan 15, 2026 at 04:28:48PM +0800, Jianping Li wrote:
> From: Ekansh Gupta <ekansh.gupta@xxxxxxxxxxxxxxxx>
> 
> The fastrpc_buf_free function currently does not handle the case where
> the input buffer pointer (buf) is NULL. This can lead to a null pointer
> dereference, causing a crash or undefined behavior when the function
> attempts to access members of the buf structure. Add a NULL check to
> ensure safe handling of NULL pointers and prevent potential crashes.

What caller passes in NULL here?  I did a quick look, and see where the
callers check this properly if it could be NULL, otherwise it all looks
sane to me.  What in-kernel user is causing a crash here?  Why not fix
the caller up instead?

thanks,

greg k-h