Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit d0d3f1b3 authored by Chao Yu's avatar Chao Yu Committed by Jaegeuk Kim
Browse files

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: default avatarChao Yu <yuchao0@huawei.com>
Signed-off-by: default avatarJaegeuk Kim <jaegeuk@kernel.org>
parent 8fe326cb

fs/f2fs/f2fs.h

+1 −0
Original line number Original line Diff line number Diff line
@@ -1047,6 +1047,7 @@ struct f2fs_sb_info { 
	struct super_block *sb;			/* pointer to VFS super block */

	struct super_block *sb;			/* pointer to VFS super block */

	struct proc_dir_entry *s_proc;		/* proc entry */

	struct proc_dir_entry *s_proc;		/* proc entry */

	struct f2fs_super_block *raw_super;	/* raw super block pointer */

	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 */

	int valid_super_block;			/* valid super block no */

	unsigned long s_flag;				/* flags for sbi */

	unsigned long s_flag;				/* flags for sbi */

fs/f2fs/file.c

+11 −8
Original line number Original line Diff line number Diff line
@@ -1962,13 +1962,15 @@ static int f2fs_ioc_get_encryption_pwsalt(struct file *filp, unsigned long arg) 
	if (!f2fs_sb_has_encrypt(inode->i_sb))

	if (!f2fs_sb_has_encrypt(inode->i_sb))

		return -EOPNOTSUPP;

		return -EOPNOTSUPP;





	if (uuid_is_nonzero(sbi->raw_super->encrypt_pw_salt))

		goto got_it;



	err = mnt_want_write_file(filp);

	err = mnt_want_write_file(filp);

	if (err)

	if (err)

		return 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 */

	/* update superblock with uuid */

	generate_random_uuid(sbi->raw_super->encrypt_pw_salt);

	generate_random_uuid(sbi->raw_super->encrypt_pw_salt);
@@ -1976,15 +1978,16 @@ static int f2fs_ioc_get_encryption_pwsalt(struct file *filp, unsigned long arg) 
	if (err) {

	if (err) {

		/* undo new data */

		/* undo new data */

		memset(sbi->raw_super->encrypt_pw_salt, 0, 16);

		memset(sbi->raw_super->encrypt_pw_salt, 0, 16);

		mnt_drop_write_file(filp);

		goto out_err;

		return err;

	}

	}

	mnt_drop_write_file(filp);

got_it:

got_it:

	if (copy_to_user((__u8 __user *)arg, sbi->raw_super->encrypt_pw_salt,

	if (copy_to_user((__u8 __user *)arg, sbi->raw_super->encrypt_pw_salt,

									16))

									16))

		return -EFAULT;

		err = -EFAULT;

	return 0;

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)

static int f2fs_ioc_gc(struct file *filp, unsigned long arg)

fs/f2fs/super.c

+2 −0
Original line number Original line Diff line number Diff line
@@ -2221,6 +2221,8 @@ static void init_sb_info(struct f2fs_sb_info *sbi) 




	sbi->dirty_device = 0;

	sbi->dirty_device = 0;

	spin_lock_init(&sbi->dev_lock);

	spin_lock_init(&sbi->dev_lock);



	mutex_init(&sbi->sb_lock);

}

}





static int init_percpu_info(struct f2fs_sb_info *sbi)

static int init_percpu_info(struct f2fs_sb_info *sbi)