[PATCH 3.19.y-ckt 50/70] ubi: Fix out of bounds write in volume update code

From: Kamal Mostafa
Date: Wed Mar 16 2016 - 16:16:49 EST


v3.19.8-ckt17 -stable review patch. If anyone has any objections, please let me know.

---8<------------------------------------------------------------

From: Richard Weinberger <richard@xxxxxx>

commit e4f6daac20332448529b11f09388f1d55ef2084c upstream.

ubi_start_leb_change() allocates too few bytes.
ubi_more_leb_change_data() will write up to req->upd_bytes +
ubi->min_io_size bytes.

Signed-off-by: Richard Weinberger <richard@xxxxxx>
Reviewed-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Kamal Mostafa <kamal@xxxxxxxxxxxxx>
---
drivers/mtd/ubi/upd.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/mtd/ubi/upd.c b/drivers/mtd/ubi/upd.c
index 2a1b6e0..0134ba3 100644
--- a/drivers/mtd/ubi/upd.c
+++ b/drivers/mtd/ubi/upd.c
@@ -193,7 +193,7 @@ int ubi_start_leb_change(struct ubi_device *ubi, struct ubi_volume *vol,
vol->changing_leb = 1;
vol->ch_lnum = req->lnum;

- vol->upd_buf = vmalloc(req->bytes);
+ vol->upd_buf = vmalloc(ALIGN((int)req->bytes, ubi->min_io_size));
if (!vol->upd_buf)
return -ENOMEM;

--
2.7.0