Merge branch 'for-linus' of git://git.kernel.dk/linux-block
[linux-2.6.git] / block / scsi_ioctl.c
index e5b1001..4f4230b 100644 (file)
@@ -35,7 +35,9 @@
 struct blk_cmd_filter {
        unsigned long read_ok[BLK_SCSI_CMD_PER_LONG];
        unsigned long write_ok[BLK_SCSI_CMD_PER_LONG];
-} blk_default_cmd_filter;
+};
+
+static struct blk_cmd_filter blk_default_cmd_filter;
 
 /* Command group 3 is reserved and should never be used.  */
 const unsigned char scsi_command_size_tbl[8] =
@@ -319,33 +321,47 @@ static int sg_io(struct request_queue *q, struct gendisk *bd_disk,
        if (hdr->iovec_count) {
                const int size = sizeof(struct sg_iovec) * hdr->iovec_count;
                size_t iov_data_len;
-               struct sg_iovec *iov;
+               struct sg_iovec *sg_iov;
+               struct iovec *iov;
+               int i;
 
-               iov = kmalloc(size, GFP_KERNEL);
-               if (!iov) {
+               sg_iov = kmalloc(size, GFP_KERNEL);
+               if (!sg_iov) {
                        ret = -ENOMEM;
                        goto out;
                }
 
-               if (copy_from_user(iov, hdr->dxferp, size)) {
-                       kfree(iov);
+               if (copy_from_user(sg_iov, hdr->dxferp, size)) {
+                       kfree(sg_iov);
                        ret = -EFAULT;
                        goto out;
                }
 
+               /*
+                * Sum up the vecs, making sure they don't overflow
+                */
+               iov = (struct iovec *) sg_iov;
+               iov_data_len = 0;
+               for (i = 0; i < hdr->iovec_count; i++) {
+                       if (iov_data_len + iov[i].iov_len < iov_data_len) {
+                               kfree(sg_iov);
+                               ret = -EINVAL;
+                               goto out;
+                       }
+                       iov_data_len += iov[i].iov_len;
+               }
+
                /* SG_IO howto says that the shorter of the two wins */
-               iov_data_len = iov_length((struct iovec *)iov,
-                                         hdr->iovec_count);
                if (hdr->dxfer_len < iov_data_len) {
-                       hdr->iovec_count = iov_shorten((struct iovec *)iov,
+                       hdr->iovec_count = iov_shorten(iov,
                                                       hdr->iovec_count,
                                                       hdr->dxfer_len);
                        iov_data_len = hdr->dxfer_len;
                }
 
-               ret = blk_rq_map_user_iov(q, rq, NULL, iov, hdr->iovec_count,
+               ret = blk_rq_map_user_iov(q, rq, NULL, sg_iov, hdr->iovec_count,
                                          iov_data_len, GFP_KERNEL);
-               kfree(iov);
+               kfree(sg_iov);
        } else if (hdr->dxfer_len)
                ret = blk_rq_map_user(q, rq, NULL, hdr->dxferp, hdr->dxfer_len,
                                      GFP_KERNEL);
@@ -675,7 +691,7 @@ int scsi_cmd_ioctl(struct request_queue *q, struct gendisk *bd_disk, fmode_t mod
 }
 EXPORT_SYMBOL(scsi_cmd_ioctl);
 
-int __init blk_scsi_ioctl_init(void)
+static int __init blk_scsi_ioctl_init(void)
 {
        blk_set_cmd_filter_defaults(&blk_default_cmd_filter);
        return 0;