Patch "nvmem: mxs-ocotp: fix buffer overflow in read" has been added to the 4.5-stable tree

Patch "nvmem: mxs-ocotp: fix buffer overflow in read" has been added to the 4.5-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    nvmem: mxs-ocotp: fix buffer overflow in read

to the 4.5-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     nvmem-mxs-ocotp-fix-buffer-overflow-in-read.patch
and it can be found in the queue-4.5 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From d1306eb675ad7a9a760b6b8e8e189824b8db89e7 Mon Sep 17 00:00:00 2001
From: Stanislav Meduna <stano@meduna.org>
Date: Mon, 2 May 2016 16:05:11 +0100
Subject: nvmem: mxs-ocotp: fix buffer overflow in read

From: Stanislav Meduna <stano@meduna.org>

commit d1306eb675ad7a9a760b6b8e8e189824b8db89e7 upstream.

This patch fixes the issue where the mxs_ocotp_read is reading
the ocotp in reg_size steps but decrements the remaining size
by 1. The number of iterations is thus four times higher,
overwriting the area behind the output buffer.

Fixes: c01e9a11ab6f ("nvmem: add driver for ocotp in i.MX23 and i.MX28")
Tested-by: Stefan Wahren <stefan.wahren@i2se.com>
Signed-off-by: Stanislav Meduna <stano@meduna.org>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/nvmem/mxs-ocotp.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

--- a/drivers/nvmem/mxs-ocotp.c
+++ b/drivers/nvmem/mxs-ocotp.c
@@ -94,7 +94,7 @@ static int mxs_ocotp_read(void *context,
 	if (ret)
 		goto close_banks;
 
-	while (val_size) {
+	while (val_size >= reg_size) {
 		if ((offset < OCOTP_DATA_OFFSET) || (offset % 16)) {
 			/* fill up non-data register */
 			*buf = 0;
@@ -103,7 +103,7 @@ static int mxs_ocotp_read(void *context,
 		}
 
 		buf++;
-		val_size--;
+		val_size -= reg_size;
 		offset += reg_size;
 	}
 


Patches currently in stable-queue which might be from stano@meduna.org are

queue-4.5/nvmem-mxs-ocotp-fix-buffer-overflow-in-read.patch