scsi: sg: allocate with __GFP_ZERO in sg_build_indirect()

This shall help avoid copying uninitialized memory to the userspace when
calling ioctl(fd, SG_IO) with an empty command.

Reported-by: syzbot+7d26fc1eea198488deab@syzkaller.appspotmail.com
Cc: stable@vger.kernel.org
Signed-off-by: Alexander Potapenko <glider@google.com>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Alexander Potapenko 2018-05-18 16:23:18 +02:00 committed by Martin K. Petersen
parent a406b0a069
commit a45b599ad8

View File

@ -1894,7 +1894,7 @@ sg_build_indirect(Sg_scatter_hold * schp, Sg_fd * sfp, int buff_size)
num = (rem_sz > scatter_elem_sz_prev) ?
scatter_elem_sz_prev : rem_sz;
schp->pages[k] = alloc_pages(gfp_mask, order);
schp->pages[k] = alloc_pages(gfp_mask | __GFP_ZERO, order);
if (!schp->pages[k])
goto out;