On 7/27/20 10:19 AM, Peilin Ye wrote: > scsi_put_cdrom_generic_arg() is copying uninitialized stack memory to > userspace due to the compiler not initializing holes in statically > allocated structures. Fix it by initializing `cgc32` using memset(). Could also just add the appropriate pad, so the compiler does the right thing. diff --git a/block/scsi_ioctl.c b/block/scsi_ioctl.c index ef722f04f88a..72108404718f 100644 --- a/block/scsi_ioctl.c +++ b/block/scsi_ioctl.c @@ -651,6 +651,7 @@ struct compat_cdrom_generic_command { compat_int_t stat; compat_caddr_t sense; unsigned char data_direction; + unsigned char pad[3]; compat_int_t quiet; compat_int_t timeout; compat_caddr_t reserved[1]; -- Jens Axboe