1 files changed, 30 insertions, 14 deletions

diff --git a/drivers/scsi/scsi_lib.c b/drivers/scsi/scsi_lib.c
index a82d2fe80fb5..88d1b5f44e59 100644
--- a/drivers/scsi/scsi_lib.c
+++ b/drivers/scsi/scsi_lib.c
@@ -65,7 +65,7 @@ static struct scsi_host_sg_pool scsi_sg_pools[] = {
 };
 #undef SP
 
-static struct kmem_cache *scsi_bidi_sdb_cache;
+static struct kmem_cache *scsi_sdb_cache;
 
 static void scsi_run_queue(struct request_queue *q);
 
@@ -207,6 +207,15 @@ int scsi_execute(struct scsi_device *sdev, const unsigned char *cmd,
 	 */
 	blk_execute_rq(req->q, NULL, req, 1);
 
+	/*
+	 * Some devices (USB mass-storage in particular) may transfer
+	 * garbage data together with a residue indicating that the data
+	 * is invalid.  Prevent the garbage from being misinterpreted
+	 * and prevent security leaks by zeroing out the excess data.
+	 */
+	if (unlikely(req->data_len > 0 && req->data_len <= bufflen))
+		memset(buffer + (bufflen - req->data_len), 0, req->data_len);
+
 	ret = req->errors;
  out:
 	blk_put_request(req);
@@ -775,7 +784,7 @@ void scsi_release_buffers(struct scsi_cmnd *cmd)
 		struct scsi_data_buffer *bidi_sdb =
 			cmd->request->next_rq->special;
 		scsi_free_sgtable(bidi_sdb);
-		kmem_cache_free(scsi_bidi_sdb_cache, bidi_sdb);
+		kmem_cache_free(scsi_sdb_cache, bidi_sdb);
 		cmd->request->next_rq->special = NULL;
 	}
 }
@@ -1050,7 +1059,7 @@ int scsi_init_io(struct scsi_cmnd *cmd, gfp_t gfp_mask)
 
 	if (blk_bidi_rq(cmd->request)) {
 		struct scsi_data_buffer *bidi_sdb = kmem_cache_zalloc(
-			scsi_bidi_sdb_cache, GFP_ATOMIC);
+			scsi_sdb_cache, GFP_ATOMIC);
 		if (!bidi_sdb) {
 			error = BLKPREP_DEFER;
 			goto err_exit;
@@ -1160,6 +1169,14 @@ int scsi_setup_fs_cmnd(struct scsi_device *sdev, struct request *req)
 
 	if (ret != BLKPREP_OK)
 		return ret;
+
+	if (unlikely(sdev->scsi_dh_data && sdev->scsi_dh_data->scsi_dh
+			 && sdev->scsi_dh_data->scsi_dh->prep_fn)) {
+		ret = sdev->scsi_dh_data->scsi_dh->prep_fn(sdev, req);
+		if (ret != BLKPREP_OK)
+			return ret;
+	}
+
 	/*
 	 * Filesystem requests must transfer data.
 	 */
@@ -1320,7 +1337,6 @@ static inline int scsi_host_queue_ready(struct request_queue *q,
 				printk("scsi%d unblocking host at zero depth\n",
 					shost->host_no));
 		} else {
-			blk_plug_device(q);
 			return 0;
 		}
 	}
@@ -1684,11 +1700,11 @@ int __init scsi_init_queue(void)
 		return -ENOMEM;
 	}
 
-	scsi_bidi_sdb_cache = kmem_cache_create("scsi_bidi_sdb",
-					sizeof(struct scsi_data_buffer),
-					0, 0, NULL);
-	if (!scsi_bidi_sdb_cache) {
-		printk(KERN_ERR "SCSI: can't init scsi bidi sdb cache\n");
+	scsi_sdb_cache = kmem_cache_create("scsi_data_buffer",
+					   sizeof(struct scsi_data_buffer),
+					   0, 0, NULL);
+	if (!scsi_sdb_cache) {
+		printk(KERN_ERR "SCSI: can't init scsi sdb cache\n");
 		goto cleanup_io_context;
 	}
 
@@ -1701,7 +1717,7 @@ int __init scsi_init_queue(void)
 		if (!sgp->slab) {
 			printk(KERN_ERR "SCSI: can't init sg slab %s\n",
 					sgp->name);
-			goto cleanup_bidi_sdb;
+			goto cleanup_sdb;
 		}
 
 		sgp->pool = mempool_create_slab_pool(SG_MEMPOOL_SIZE,
@@ -1709,13 +1725,13 @@ int __init scsi_init_queue(void)
 		if (!sgp->pool) {
 			printk(KERN_ERR "SCSI: can't init sg mempool %s\n",
 					sgp->name);
-			goto cleanup_bidi_sdb;
+			goto cleanup_sdb;
 		}
 	}
 
 	return 0;
 
-cleanup_bidi_sdb:
+cleanup_sdb:
 	for (i = 0; i < SG_MEMPOOL_NR; i++) {
 		struct scsi_host_sg_pool *sgp = scsi_sg_pools + i;
 		if (sgp->pool)
@@ -1723,7 +1739,7 @@ cleanup_bidi_sdb:
 		if (sgp->slab)
 			kmem_cache_destroy(sgp->slab);
 	}
-	kmem_cache_destroy(scsi_bidi_sdb_cache);
+	kmem_cache_destroy(scsi_sdb_cache);
 cleanup_io_context:
 	kmem_cache_destroy(scsi_io_context_cache);
 
@@ -1735,7 +1751,7 @@ void scsi_exit_queue(void)
 	int i;
 
 	kmem_cache_destroy(scsi_io_context_cache);
-	kmem_cache_destroy(scsi_bidi_sdb_cache);
+	kmem_cache_destroy(scsi_sdb_cache);
 
 	for (i = 0; i < SG_MEMPOOL_NR; i++) {
 		struct scsi_host_sg_pool *sgp = scsi_sg_pools + i;