[PATCH 3/5] efi_memory: avoid possible null pointer dereference

[Ilias Apalodimas]

On Wed, 31 Jul 2024 at 09:19, Heinrich Schuchardt <xypron.glpk at gmx.de> wrote:
>
> On 7/30/24 13:11, Sughosh Ganu wrote:
> > Populate the previous memory descriptor node pointer only after it's
> > parent struct has been initialised. The compiler fixes this logic to
> > do the right thing, but it is better to have correct code in place.
> >
> > Signed-off-by: Sughosh Ganu <sughosh.ganu at linaro.org>
>
> Fixes: 7b05667ce239 ("efi_loader: Merge memory map entries")
> Reviewed-by: Heinrich Schuchardt <xypron.glpk at gmx.de>
>
> > ---
> >   lib/efi_loader/efi_memory.c | 3 ++-
> >   1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/lib/efi_loader/efi_memory.c b/lib/efi_loader/efi_memory.c
> > index bfadd6bd41..8d4f6e339d 100644
> > --- a/lib/efi_loader/efi_memory.c
> > +++ b/lib/efi_loader/efi_memory.c
> > @@ -138,7 +138,7 @@ static void efi_mem_sort(void)
> >               merge_again = false;
> >               list_for_each(lhandle, &efi_mem) {
> >                       struct efi_mem_list *lmem;
> > -                     struct efi_mem_desc *prev = &prevmem->desc;
> > +                     struct efi_mem_desc *prev;
> >                       struct efi_mem_desc *cur;
> >                       uint64_t pages;
> >
> > @@ -149,6 +149,7 @@ static void efi_mem_sort(void)
> >                       }
> >
> >                       cur = &lmem->desc;
> > +                     prev = &prevmem->desc;
> >
> >                       if ((desc_get_end(cur) == prev->physical_start) &&
> >                           (prev->type == cur->type) &&
>

Reviewed-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>