Merge branch 'linux-next' of git://git.infradead.org/ubifs-2.6

* 'linux-next' of git://git.infradead.org/ubifs-2.6:
  UBI: fix use-after-free on error path
  UBI: fix missing scrub when there is a bit-flip
  UBIFS: Use kmemdup rather than duplicating its implementation

3 files changed, 14 insertions, 6 deletions

diff --git a/drivers/mtd/ubi/eba.c b/drivers/mtd/ubi/eba.c
index fb7f19b..cd26da8 100644
--- a/drivers/mtd/ubi/eba.c
+++ b/drivers/mtd/ubi/eba.c
@@ -1028,12 +1028,14 @@ int ubi_eba_copy_leb(struct ubi_device *ubi, int from, int to,
 	 * 'ubi_wl_put_peb()' function on the @ubi->move_mutex. In turn, we are
 	 * holding @ubi->move_mutex and go sleep on the LEB lock. So, if the
 	 * LEB is already locked, we just do not move it and return
-	 * %MOVE_CANCEL_RACE, which means that UBI will re-try, but later.
+	 * %MOVE_RETRY. Note, we do not return %MOVE_CANCEL_RACE here because
+	 * we do not know the reasons of the contention - it may be just a
+	 * normal I/O on this LEB, so we want to re-try.
 	 */
 	err = leb_write_trylock(ubi, vol_id, lnum);
 	if (err) {
 		dbg_wl("contention on LEB %d:%d, cancel", vol_id, lnum);
-		return MOVE_CANCEL_RACE;
+		return MOVE_RETRY;
 	}
 
 	/*
diff --git a/drivers/mtd/ubi/ubi.h b/drivers/mtd/ubi/ubi.h
index dc64c76..d51d75d 100644
--- a/drivers/mtd/ubi/ubi.h
+++ b/drivers/mtd/ubi/ubi.h
@@ -120,6 +120,7 @@ enum {
  *                     PEB
  * MOVE_CANCEL_BITFLIPS: canceled because a bit-flip was detected in the
  *                       target PEB
+ * MOVE_RETRY: retry scrubbing the PEB
  */
 enum {
 	MOVE_CANCEL_RACE = 1,
@@ -127,6 +128,7 @@ enum {
 	MOVE_TARGET_RD_ERR,
 	MOVE_TARGET_WR_ERR,
 	MOVE_CANCEL_BITFLIPS,
+	MOVE_RETRY,
 };
 
 /**
diff --git a/drivers/mtd/ubi/wl.c b/drivers/mtd/ubi/wl.c
index 42c684c..0696e36 100644
--- a/drivers/mtd/ubi/wl.c
+++ b/drivers/mtd/ubi/wl.c
@@ -795,7 +795,10 @@ static int wear_leveling_worker(struct ubi_device *ubi, struct ubi_work *wrk,
 			protect = 1;
 			goto out_not_moved;
 		}
-
+		if (err == MOVE_RETRY) {
+			scrubbing = 1;
+			goto out_not_moved;
+		}
 		if (err == MOVE_CANCEL_BITFLIPS || err == MOVE_TARGET_WR_ERR ||
 		    err == MOVE_TARGET_RD_ERR) {
 			/*
@@ -1049,7 +1052,6 @@ static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk,
 
 	ubi_err("failed to erase PEB %d, error %d", pnum, err);
 	kfree(wl_wrk);
-	kmem_cache_free(ubi_wl_entry_slab, e);
 
 	if (err == -EINTR || err == -ENOMEM || err == -EAGAIN ||
 	    err == -EBUSY) {
@@ -1062,14 +1064,16 @@ static int erase_worker(struct ubi_device *ubi, struct ubi_work *wl_wrk,
 			goto out_ro;
 		}
 		return err;
-	} else if (err != -EIO) {
+	}
+
+	kmem_cache_free(ubi_wl_entry_slab, e);
+	if (err != -EIO)
 		/*
 		 * If this is not %-EIO, we have no idea what to do. Scheduling
 		 * this physical eraseblock for erasure again would cause
 		 * errors again and again. Well, lets switch to R/O mode.
 		 */
 		goto out_ro;
-	}
 
 	/* It is %-EIO, the PEB went bad */