diff options
| author | Chao Yu <chao2.yu@samsung.com> | 2014-05-28 08:56:09 +0800 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2014-06-04 13:34:30 +0900 |
| commit | bfec07d0f8ed78b10df3ca3bc23e27de1166ea45 (patch) | |
| tree | c6134dfc647176474944cbb244bd15de4d4607ac /fs/f2fs/dir.c | |
| parent | d631abdac9d541d282a1461b5aeae70aa3866e9f (diff) | |
f2fs: avoid overflow when large directory feathure is enabled
When large directory feathure is enable, We have one case which could cause
overflow in dir_buckets() as following:
special case: level + dir_level >= 32 and level < MAX_DIR_HASH_DEPTH / 2.
Here we define MAX_DIR_BUCKETS to limit the return value when the condition
could trigger potential overflow.
Changes from V1
o modify description of calculation in f2fs.txt suggested by Changman Lee.
Suggested-by: Changman Lee <cm224.lee@samsung.com>
Signed-off-by: Chao Yu <chao2.yu@samsung.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs/dir.c')
| -rw-r--r-- | fs/f2fs/dir.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/fs/f2fs/dir.c b/fs/f2fs/dir.c index c3f148555c37..966acb039e3b 100644 --- a/fs/f2fs/dir.c +++ b/fs/f2fs/dir.c @@ -23,10 +23,10 @@ static unsigned long dir_blocks(struct inode *inode) static unsigned int dir_buckets(unsigned int level, int dir_level) { - if (level < MAX_DIR_HASH_DEPTH / 2) + if (level + dir_level < MAX_DIR_HASH_DEPTH / 2) return 1 << (level + dir_level); else - return 1 << ((MAX_DIR_HASH_DEPTH / 2 + dir_level) - 1); + return MAX_DIR_BUCKETS; } static unsigned int bucket_blocks(unsigned int level) |