4.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Heiko Carstens <heiko.carstens@xxxxxxxxxx> commit 4920e3cf77347d7d7373552d4839e8d832321313 upstream. The current implementation of setup_randomness uses the stack address and therefore the pointer to the SYSIB 3.2.2 block as input data address. Furthermore the length of the input data is the number of virtual-machine description blocks which is typically one. This means that typically a single zero byte is fed to add_device_randomness. Fix both of these and use the address of the first virtual machine description block as input data address and also use the correct length. Fixes: bcfcbb6bae64 ("s390: add system information as device randomness") Signed-off-by: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Signed-off-by: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/s390/kernel/setup.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/s390/kernel/setup.c +++ b/arch/s390/kernel/setup.c @@ -822,7 +822,7 @@ static void __init setup_randomness(void vmms = (struct sysinfo_3_2_2 *) memblock_alloc(PAGE_SIZE, PAGE_SIZE); if (stsi(vmms, 3, 2, 2) == 0 && vmms->count) - add_device_randomness(&vmms, vmms->count); + add_device_randomness(&vmms->vm, sizeof(vmms->vm[0]) * vmms->count); memblock_free((unsigned long) vmms, PAGE_SIZE); }