On Thu, Sep 24, 2020 at 12:02 PM +0200, Philippe Mathieu-Daudé
<phi...@redhat.com> wrote:
> Hi Marc,
>
> On 9/24/20 10:59 AM, Marc Hartmayer wrote:
>> This error takes effect when the magic value "zIPL" is located at the
>> end of a block. For example if s2_cur_blk = 0x7fe18000 and the magic
>> value "zIPL" is located at 0x7fe18ffc - 0x7fe18fff.
>>
>> Fixes: ba831b25262a ("s390-ccw: read stage2 boot loader data to find menu")
>> Reviewed-by: Collin Walling <wall...@linux.ibm.com>
>> Signed-off-by: Marc Hartmayer <mhart...@linux.ibm.com>
>> ---
>> pc-bios/s390-ccw/bootmap.c | 2 +-
>> 1 file changed, 1 insertion(+), 1 deletion(-)
>>
>> diff --git a/pc-bios/s390-ccw/bootmap.c b/pc-bios/s390-ccw/bootmap.c
>> index 97205674e59a..0d29dceaa3cc 100644
>> --- a/pc-bios/s390-ccw/bootmap.c
>> +++ b/pc-bios/s390-ccw/bootmap.c
>> @@ -163,7 +163,7 @@ static bool find_zipl_boot_menu_banner(int *offset)
>> int i;
>>
>> /* Menu banner starts with "zIPL" */
>> - for (i = 0; i < virtio_get_block_size() - 4; i++) {
>> + for (i = 0; i < virtio_get_block_size() - 3; i++) {
>
> Easier to review as:
>
> for (i = 0; i <= virtio_get_block_size() - 4; i++) {
Yep.
>
> Even easier defining ZIPL_MAGIC_SIZE instead of the magic '4'.
I thought about adding such a macro as well. Makes even more sense with
your proposed change.
>
>> if (magic_match(s2_cur_blk + i, ZIPL_MAGIC_EBCDIC)) {
>> *offset = i;
>> return true;
>>
>
--
Kind regards / Beste Grüße
Marc Hartmayer
IBM Deutschland Research & Development GmbH
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