diff options
| author | Chao Yu <yuchao0@huawei.com> | 2018-02-11 22:53:20 +0800 |
|---|---|---|
| committer | Jaegeuk Kim <jaegeuk@kernel.org> | 2018-04-08 03:51:00 -0700 |
| commit | 4d409fa3346bf97cc68435cf49a6ab7c5733b27f (patch) | |
| tree | 3b824346c883ae5a7e3d4725328d5a0ed6880600 | |
| parent | 1f6bac14c10061c2556deb4bf50600971d911b50 (diff) | |
f2fs: introduce sb_lock to make encrypt pwsalt update exclusive
f2fs_super_block.encrypt_pw_salt can be udpated and persisted
concurrently, result in getting different pwsalt in separated
threads, so let's introduce sb_lock to exclude concurrent
accessers.
Signed-off-by: Chao Yu <yuchao0@huawei.com>
Signed-off-by: Jaegeuk Kim <jaegeuk@kernel.org>
| -rw-r--r-- | fs/f2fs/f2fs.h | 1 | ||||
| -rw-r--r-- | fs/f2fs/file.c | 19 | ||||
| -rw-r--r-- | fs/f2fs/super.c | 2 |
3 files changed, 14 insertions, 8 deletions
diff --git a/fs/f2fs/f2fs.h b/fs/f2fs/f2fs.h index 1653f6010495..a8ea66cb45ed 100644 --- a/fs/f2fs/f2fs.h +++ b/fs/f2fs/f2fs.h @@ -1111,6 +1111,7 @@ struct f2fs_sb_info { struct super_block *sb; /* pointer to VFS super block */ struct proc_dir_entry *s_proc; /* proc entry */ struct f2fs_super_block *raw_super; /* raw super block pointer */ + struct mutex sb_lock; /* lock for raw super block */ int valid_super_block; /* valid super block no */ unsigned long s_flag; /* flags for sbi */ diff --git a/fs/f2fs/file.c b/fs/f2fs/file.c index 7c7d0477c057..9152fb41764a 100644 --- a/fs/f2fs/file.c +++ b/fs/f2fs/file.c @@ -1960,13 +1960,15 @@ static int f2fs_ioc_get_encryption_pwsalt(struct file *filp, unsigned long arg) if (!f2fs_sb_has_encrypt(inode->i_sb)) return -EOPNOTSUPP; - if (uuid_is_nonzero(sbi->raw_super->encrypt_pw_salt)) - goto got_it; - err = mnt_want_write_file(filp); if (err) return err; + mutex_lock(&sbi->sb_lock); + + if (uuid_is_nonzero(sbi->raw_super->encrypt_pw_salt)) + goto got_it; + /* update superblock with uuid */ generate_random_uuid(sbi->raw_super->encrypt_pw_salt); @@ -1974,15 +1976,16 @@ static int f2fs_ioc_get_encryption_pwsalt(struct file *filp, unsigned long arg) if (err) { /* undo new data */ memset(sbi->raw_super->encrypt_pw_salt, 0, 16); - mnt_drop_write_file(filp); - return err; + goto out_err; } - mnt_drop_write_file(filp); got_it: if (copy_to_user((__u8 __user *)arg, sbi->raw_super->encrypt_pw_salt, 16)) - return -EFAULT; - return 0; + err = -EFAULT; +out_err: + mutex_unlock(&sbi->sb_lock); + mnt_drop_write_file(filp); + return err; } static int f2fs_ioc_gc(struct file *filp, unsigned long arg) diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c index b6d70d6d8a27..f86374cc4470 100644 --- a/fs/f2fs/super.c +++ b/fs/f2fs/super.c @@ -2225,6 +2225,8 @@ static void init_sb_info(struct f2fs_sb_info *sbi) sbi->dirty_device = 0; spin_lock_init(&sbi->dev_lock); + + mutex_init(&sbi->sb_lock); } static int init_percpu_info(struct f2fs_sb_info *sbi) |