Hi Joel, On 25.01.26 00:18, Joel Fernandes wrote: > Use checked_add() and checked_mul() when computing offsets from > firmware-provided values in new_fwsec(). > > Without checked arithmetic, corrupt firmware could cause integer overflow. The > danger is not just wrapping to a huge value, but potentially wrapping to a > small plausible offset that passes validation yet accesses entirely wrong > data, > causing silent corruption or security issues. > > Signed-off-by: Joel Fernandes <[email protected]> > --- > drivers/gpu/nova-core/firmware/fwsec.rs | 60 ++++++++++++++----------- > 1 file changed, 35 insertions(+), 25 deletions(-) > > diff --git a/drivers/gpu/nova-core/firmware/fwsec.rs > b/drivers/gpu/nova-core/firmware/fwsec.rs > index a8ec08a500ac..1a91bbbce3d5 100644 > --- a/drivers/gpu/nova-core/firmware/fwsec.rs > +++ b/drivers/gpu/nova-core/firmware/fwsec.rs > @@ -46,10 +46,7 @@ ... > @@ -356,8 +362,12 @@ pub(crate) fn new( > // Patch signature if needed. > let desc = bios.fwsec_image().header()?; > let ucode_signed = if desc.signature_count() != 0 { > - let sig_base_img = > - usize::from_safe_cast(desc.imem_load_size() + > desc.pkc_data_offset()); > + // Compute sig_base_img = desc.imem_load_size + > desc.pkc_data_offset.
Nit: Drop `desc.` to make it consistent with the other comments. Best regards Dirk
