From: Minchan Kim <minchan@kernel.org>
Date: Mon, 3 Mar 2014 23:38:34 +0000 (-0800)
Subject: zram: avoid null access when fail to alloc meta
X-Git-Tag: firefly_0821_release~3680^2~8^2^2~53
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=b048aa137fe66b7f19d842a4b145296bbc26caff;p=firefly-linux-kernel-4.4.55.git

zram: avoid null access when fail to alloc meta

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

Signed-off-by: Minchan Kim <minchan@kernel.org>
Acked-by: Jerome Marchand <jmarchan@redhat.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
(cherry picked from commit db5d711e2db776f18219b033e5dc4fb7e4264dd7)
Signed-off-by: Alex Shi <alex.shi@linaro.org>
---

diff --git a/drivers/block/zram/zram_drv.c b/drivers/block/zram/zram_drv.c
index c450dd9390ab..cf77a8a1ae97 100644
--- a/drivers/block/zram/zram_drv.c
+++ b/drivers/block/zram/zram_drv.c
@@ -611,6 +611,8 @@ 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);