Guillaume Knispel wrote:
> There is an error in rh_alloc_fixed() of the Remote Heap code:
> If there is at least one free block blk won't be NULL at the end of the
> search loop, so -ENOMEM won't be returned and the else branch of
> "if (bs == s || be == e)" will be taken, corrupting the management
> structures.
>
> Signed-off-by: Guillaume Knispel <[EMAIL PROTECTED]>
> ---
> Fix an error in rh_alloc_fixed() that made allocations succeed when
> they should fail, and corrupted management structures.
>
> diff --git a/arch/powerpc/lib/rheap.c b/arch/powerpc/lib/rheap.c
> index 29b2941..45907c1 100644
> --- a/arch/powerpc/lib/rheap.c
> +++ b/arch/powerpc/lib/rheap.c
> @@ -556,6 +556,7 @@ unsigned long rh_alloc_fixed(rh_info_t * info, unsigned
> long start, int size, co
> be = blk->start + blk->size;
> if (s >= bs && e <= be)
> break;
> + blk = NULL;
> }
>
> if (blk == NULL)
This is a good catch, however, wouldn't it be better to do this:
list_for_each(l, &info->free_list) {
blk = list_entry(l, rh_block_t, list);
/* The range must lie entirely inside one free block */
bs = blk->start;
be = blk->start + blk->size;
if (s >= bs && e <= be)
break;
}
- if (blk == NULL)
+ if (blk == &info->free_list)
return (unsigned long) -ENOMEM;
I haven't tested this, but the if-statement at the end of the loop is meant to
check whether the list_for_each() loop got to the end or not.
What do you think?
--
Timur Tabi
Linux kernel developer at Freescale
_______________________________________________
Linuxppc-dev mailing list
Linuxppc-dev@ozlabs.org
https://ozlabs.org/mailman/listinfo/linuxppc-dev
