Skip to contentSkip to conversation

Patch "zram: fix operator precedence to get offset" has been added to the 4.4-stable tree

PATCH [email protected] 2 participants 2 messages Apr 18, 2017 – Apr 19, 2017

Subsystems (3)
Stable branch Block layer zram
lore
Share & tools
lore

[email protected]

author maintainer Applied
#0 lore raw

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

zram: fix operator precedence to get offset

to the 4.4-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:
zram-fix-operator-precedence-to-get-offset.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

Quoted 1 line

From 4ca82dabc9fbf7bc5322aa54d802cb3cb7b125c5 Mon Sep 17 00:00:00 2001

From: Minchan Kim <[email protected]>
Date: Thu, 13 Apr 2017 14:56:35 -0700
Subject: zram: fix operator precedence to get offset

From: Minchan Kim <[email protected]>

commit 4ca82dabc9fbf7bc5322aa54d802cb3cb7b125c5 upstream.

In zram_rw_page, the logic to get offset is wrong by operator precedence (i.e., "<<" is higher than "&"). With wrong offset, zram can corrupt the user's data. This patch fixes it.

Fixes 8c7f01025 ("zram: implement rw_page operation of zram")
Link http://lkml.kernel.org/r/[email protected] open here
Signed-off-by Minchan Kim <[email protected]>
Cc Sergey Senozhatsky <[email protected]>
Signed-off-by Andrew Morton <[email protected]>
Signed-off-by Linus Torvalds <[email protected]>
Signed-off-by Greg Kroah-Hartman <[email protected]>
---
 drivers/block/zram/zram_drv.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)
drivers/block/zram/zram_drv.c +1 -1
@@ -953,7 +953,7 @@ static int zram_rw_page(struct block_dev
 	}
 
 	index = sector >> SECTORS_PER_PAGE_SHIFT;
-	offset = sector & (SECTORS_PER_PAGE - 1) << SECTOR_SHIFT;
+	offset = (sector & (SECTORS_PER_PAGE - 1)) << SECTOR_SHIFT;
 
 	bv.bv_page = page;
 	bv.bv_len = PAGE_SIZE;

Patches currently in stable-queue which might be from [email protected] are

queue-4.4/zram-fix-operator-precedence-to-get-offset.patch

maintainer
#1 lore raw

Hello Greg,

Quoted 29 lines · On Tue, Apr 18, 2017 at 02:49:47PM +0200, [email protected] wrote:

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

zram: fix operator precedence to get offset

to the 4.4-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:
zram-fix-operator-precedence-to-get-offset.patch
and it can be found in the queue-4.4 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree, please let <[email protected]> know about it.

From 4ca82dabc9fbf7bc5322aa54d802cb3cb7b125c5 Mon Sep 17 00:00:00 2001
From: Minchan Kim <[email protected]>
Date: Thu, 13 Apr 2017 14:56:35 -0700
Subject: zram: fix operator precedence to get offset

From: Minchan Kim <[email protected]>

commit 4ca82dabc9fbf7bc5322aa54d802cb3cb7b125c5 upstream.

In zram_rw_page, the logic to get offset is wrong by operator precedence (i.e., "<<" is higher than "&"). With wrong offset, zram can corrupt the user's data. This patch fixes it.

Quoted 7 lines
Fixes 8c7f01025 ("zram: implement rw_page operation of zram")
Link http://lkml.kernel.org/r/[email protected] open here
Signed-off-by Minchan Kim <[email protected]>
Cc Sergey Senozhatsky <[email protected]>
Signed-off-by Andrew Morton <[email protected]>
Signed-off-by Linus Torvalds <[email protected]>
Signed-off-by Greg Kroah-Hartman <[email protected]>

After Linus merging this patch, I got realized that patch itself is correct but no need to apply this patch to the stable by review from Sergey. Sorry about the noise.

Please drop this patch.