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>
torvalds · May 18, 2018 · a45b599 · a45b599
1 parent a406b0a
commit a45b599
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
@@ -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;