[3.11.y.z extended stable] Patch "zram: avoid null access when fail to alloc meta" has been added to staging queue

[Luis Henriques]

This is a note to let you know that I have just added a patch titled

    zram: avoid null access when fail to alloc meta

to the linux-3.11.y-queue branch of the 3.11.y.z extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.11.y-queue

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.11.y.z tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Luis

------

>From 6adb52d8f44969875326b300f8be84846ed9c47a Mon Sep 17 00:00:00 2001
From: Minchan Kim <minchan at kernel.org>
Date: Mon, 3 Mar 2014 15:38:34 -0800
Subject: zram: avoid null access when fail to alloc meta

commit db5d711e2db776f18219b033e5dc4fb7e4264dd7 upstream.

zram_meta_alloc could fail so caller should check it.  Otherwise, your
system will hang.

Signed-off-by: Minchan Kim <minchan at kernel.org>
Acked-by: Jerome Marchand <jmarchan at redhat.com>
Signed-off-by: Andrew Morton <akpm at linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds at linux-foundation.org>
[ luis: backported to 3.11:
  - zram is a staging driver in 3.11 kernel ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
---
 drivers/staging/zram/zram_drv.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/staging/zram/zram_drv.c b/drivers/staging/zram/zram_drv.c
index fc540ea..9f1cb4e0 100644
--- a/drivers/staging/zram/zram_drv.c
+++ b/drivers/staging/zram/zram_drv.c
@@ -620,6 +620,8 @@ static ssize_t disksize_store(struct device *dev,

 	disksize = PAGE_ALIGN(disksize);
 	meta = zram_meta_alloc(disksize);
+	if (!meta)
+		return -ENOMEM;
 	down_write(&zram->init_lock);
 	if (zram->init_done) {
 		up_write(&zram->init_lock);
--
1.9.0