[PATCH] UBI: Validate data_size

Richard Weinberger
2015-09-22T21:58:16Z

Make sure that data_size is less than LEB size.
Otherwise a handcrafted UBI image is able to trigger
an out of bounds memory access in ubi_compare_lebs().

Cc: stable@vger.kernel.org
Signed-off-by: Richard Weinberger <richard@nod.at>
---
drivers/mtd/ubi/io.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/mtd/ubi/io.c b/drivers/mtd/ubi/io.c
index 5bbd1f0..1fc23e4 100644
--- a/drivers/mtd/ubi/io.c
+++ b/drivers/mtd/ubi/io.c
@@ -926,6 +926,11 @@ static int validate_vid_hdr(const struct ubi_device *ubi,
goto bad;
}

+ if (data_size > ubi->leb_size) {
+ ubi_err(ubi, "bad data_size");
+ goto bad;
+ }
+
if (vol_type == UBI_VID_STATIC) {
/*
* Although from high-level point of view static volumes may
--
1.8.4.5