[merged] memcg-avoid-overflow-caused-by-page_align.patch removed from -mm tree

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Subject: [merged] memcg-avoid-overflow-caused-by-page_align.patch removed from -mm tree
To: handai.szj@xxxxxxxxxx,h.huangqiang@xxxxxxxxxx,jeff.liu@xxxxxxxxxx,mhocko@xxxxxxx,nishimura@xxxxxxxxxxxxxxxxx,mm-commits@xxxxxxxxxxxxxxx
From: akpm@xxxxxxxxxxxxxxxxxxxx
Date: Fri, 13 Sep 2013 13:02:38 -0700


The patch titled
     Subject: memcg: avoid overflow caused by PAGE_ALIGN
has been removed from the -mm tree.  Its filename was
     memcg-avoid-overflow-caused-by-page_align.patch

This patch was dropped because it was merged into mainline or a subsystem tree

------------------------------------------------------
From: Sha Zhengju <handai.szj@xxxxxxxxxx>
Subject: memcg: avoid overflow caused by PAGE_ALIGN

Since PAGE_ALIGN is aligning up(the next page boundary), so after
PAGE_ALIGN, the value might be overflow, such as write the MAX value to
*.limit_in_bytes.

$ cat /cgroup/memory/memory.limit_in_bytes
18446744073709551615

# echo 18446744073709551615 > /cgroup/memory/memory.limit_in_bytes
bash: echo: write error: Invalid argument

Some user programs might depend on such behaviours(like libcg, we read the
value in snapshot, then use the value to reset cgroup later), and that
will cause confusion.  So we need to fix it.

Signed-off-by: Sha Zhengju <handai.szj@xxxxxxxxxx>
Signed-off-by: Qiang Huang <h.huangqiang@xxxxxxxxxx>
Acked-by: Michal Hocko <mhocko@xxxxxxx>
Cc: Daisuke Nishimura <nishimura@xxxxxxxxxxxxxxxxx>
Cc: Jeff Liu <jeff.liu@xxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---

 kernel/res_counter.c |    6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff -puN kernel/res_counter.c~memcg-avoid-overflow-caused-by-page_align kernel/res_counter.c
--- a/kernel/res_counter.c~memcg-avoid-overflow-caused-by-page_align
+++ a/kernel/res_counter.c
@@ -195,6 +195,10 @@ int res_counter_memparse_write_strategy(
 	if (*end != '\0')
 		return -EINVAL;
 
-	*res = PAGE_ALIGN(*res);
+	if (PAGE_ALIGN(*res) >= *res)
+		*res = PAGE_ALIGN(*res);
+	else
+		*res = RES_COUNTER_MAX;
+
 	return 0;
 }
_

Patches currently in -mm which might be from handai.szj@xxxxxxxxxx are

origin.patch

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