[PATCH] partitions: efi: Check GPT header size against minimum limit

[Sascha Hauer]

On Wed, Dec 04, 2024 at 09:18:58PM +0300, Alexander Shiyan wrote:
> Hello.
> 
> Maybe it's better to use sizeof(struct _gpt_header) ?

Changed to use sizeof while applying

Sascha

> 
> Thanks!
> 
> ср, 4 дек. 2024 г. в 18:30, Abdelrahman Youssef <abdelrahmanyossef12 at gmail.com>:
> >
> > In https://git.pengutronix.de/cgit/barebox/commit/?id=a9c6ad764144, we were
> > checking if the GPT header size is exceeding the maximum limit.
> >
> > This is a follow-up patch to check if the header size is less than
> > the minimum limit which is 92 as per this documentation
> > https://uefi.org/specs/UEFI/2.10/05_GUID_Partition_Table_Format.html#id14
> >
> > Signed-off-by: Abdelrahman Youssef <abdelrahmanyossef12 at gmail.com>
> > ---
> >  common/partitions/efi.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/common/partitions/efi.c b/common/partitions/efi.c
> > index 8014579b67..a4e60c3c98 100644
> > --- a/common/partitions/efi.c
> > +++ b/common/partitions/efi.c
> > @@ -190,7 +190,8 @@ static int is_gpt_valid(struct block_device *blk, u64 lba,
> >                 goto fail;
> >         }
> >
> > -       if (le32_to_cpu((*gpt)->header_size) > bdev_logical_block_size(blk))
> > +       if (le32_to_cpu((*gpt)->header_size) < 92 ||
> > +        le32_to_cpu((*gpt)->header_size) > bdev_logical_block_size(blk))
> >                 goto fail;
> >
> >         /* Check the GUID Partition Table CRC */
> > --
> > 2.43.0
> >
> >
> 
> 

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