linux-kernel - Re: [PATCH v4 19/20] gpu: nova-core: extract FWSEC from BIOS and patch it to run FWSEC-FRTS

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <aEAjASkf9t4s4RsY@cassiopeiae>
Date: Wed, 4 Jun 2025 12:42:09 +0200
From: Danilo Krummrich <dakr@...nel.org>
To: Alexandre Courbot <acourbot@...dia.com>
Cc: Miguel Ojeda <ojeda@...nel.org>, Alex Gaynor <alex.gaynor@...il.com>,
	Boqun Feng <boqun.feng@...il.com>, Gary Guo <gary@...yguo.net>,
	Björn Roy Baron <bjorn3_gh@...tonmail.com>,
	Benno Lossin <benno.lossin@...ton.me>,
	Andreas Hindborg <a.hindborg@...nel.org>,
	Alice Ryhl <aliceryhl@...gle.com>, Trevor Gross <tmgross@...ch.edu>,
	David Airlie <airlied@...il.com>, Simona Vetter <simona@...ll.ch>,
	Maarten Lankhorst <maarten.lankhorst@...ux.intel.com>,
	Maxime Ripard <mripard@...nel.org>,
	Thomas Zimmermann <tzimmermann@...e.de>,
	John Hubbard <jhubbard@...dia.com>, Ben Skeggs <bskeggs@...dia.com>,
	Joel Fernandes <joelagnelf@...dia.com>,
	Timur Tabi <ttabi@...dia.com>, Alistair Popple <apopple@...dia.com>,
	linux-kernel@...r.kernel.org, rust-for-linux@...r.kernel.org,
	nouveau@...ts.freedesktop.org, dri-devel@...ts.freedesktop.org
Subject: Re: [PATCH v4 19/20] gpu: nova-core: extract FWSEC from BIOS and
 patch it to run FWSEC-FRTS

On Wed, May 21, 2025 at 03:45:14PM +0900, Alexandre Courbot wrote:
> +impl FirmwareDmaObject<FwsecFirmware> {
> +    /// Patch the Fwsec firmware image in `fw` to run the command `cmd`.
> +    fn patch_command(&mut self, v3_desc: &FalconUCodeDescV3, cmd: FwsecCommand) -> Result<()> {

Same comment as on the previous patch regarding patch_signature().

<snip>

> +    fn dmem_load_params(&self) -> FalconLoadTarget {
> +        FalconLoadTarget {
> +            src_start: self.desc.imem_load_size,
> +            dst_start: self.desc.dmem_phys_base,
> +            len: Layout::from_size_align(self.desc.dmem_load_size as usize, 256)
> +                // Cannot panic, as 256 is non-zero and a power of 2.
> +                .unwrap()

There is also Layout::from_size_align_unchecked(), which I prefer over unwrap().
I think we should never use unwrap() and rather the unsafe variant, which at least
forces us to document things properly, if there's no other option.

In this case, however, I don't see why we can't just propage the error? This
method is used from Falcon::dma_load(), which returns a Result anyways, so let's
just propagate it.

In general, we should *never* potentially panic the whole kernel just because
of a wrong size calculation in a driver.