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author | Chao Yu <yuchao0@huawei.com> | 2018-08-05 18:04:25 +0300 |
---|---|---|
committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2018-08-13 20:48:17 +0300 |
commit | a33c150237a20d97a174243bc658c86502f9d370 (patch) | |
tree | 1bdaea29bcb138882d6318eb3e151b2febceba2a /fs/f2fs/data.c | |
parent | c7079853c859c910b9d047a37891b4aafb8f8dd7 (diff) | |
download | linux-a33c150237a20d97a174243bc658c86502f9d370.tar.xz |
f2fs: fix avoid race between truncate and background GC
Thread A Background GC
- f2fs_setattr isize to 0
- truncate_setsize
- gc_data_segment
- f2fs_get_read_data_page page #0
- set_page_dirty
- set_cold_data
- f2fs_truncate
- f2fs_setattr isize to 4k
- read 4k <--- hit data in cached page #0
Above race condition can cause read out invalid data in a truncated
page, fix it by i_gc_rwsem[WRITE] lock.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
Diffstat (limited to 'fs/f2fs/data.c')
-rw-r--r-- | fs/f2fs/data.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index 1e6cc68fb7c4..45f043ee48bd 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -2199,8 +2199,12 @@ static void f2fs_write_failed(struct address_space *mapping, loff_t to) if (to > i_size) { down_write(&F2FS_I(inode)->i_mmap_sem); + down_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); + truncate_pagecache(inode, i_size); f2fs_truncate_blocks(inode, i_size, true); + + up_write(&F2FS_I(inode)->i_gc_rwsem[WRITE]); up_write(&F2FS_I(inode)->i_mmap_sem); } } |