Commit 43be0ec0 authored by Zhu Yanhai's avatar Zhu Yanhai Committed by Ryusuke Konishi
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nilfs2: add more check routines in mount process 



nilfs2: Add more safeguard routines and protections in mount process,
which also makes nilfs2 report consistency error messages when
checkpoint number is invalid.

Signed-off-by: default avatarZhu Yanhai <zhu.yanhai@gmail.com>
Signed-off-by: default avatarRyusuke Konishi <konishi.ryusuke@lab.ntt.co.jp>
parent a4f0b9c5

fs/nilfs2/cpfile.c

+8 −3
Original line number Diff line number Diff line
@@ -815,8 +815,10 @@ int nilfs_cpfile_is_snapshot(struct inode *cpfile, __u64 cno) 
	void *kaddr;

	int ret;



	if (cno == 0)

		return -ENOENT; /* checkpoint number 0 is invalid */

	/* CP number is invalid if it's zero or larger than the

	largest	exist one.*/

	if (cno == 0 || cno >= nilfs_mdt_cno(cpfile))

		return -ENOENT;

	down_read(&NILFS_MDT(cpfile)->mi_sem);



	ret = nilfs_cpfile_get_checkpoint_block(cpfile, cno, 0, &bh);
@@ -824,6 +826,9 @@ int nilfs_cpfile_is_snapshot(struct inode *cpfile, __u64 cno) 
		goto out;

	kaddr = kmap_atomic(bh->b_page, KM_USER0);

	cp = nilfs_cpfile_block_get_checkpoint(cpfile, cno, bh, kaddr);

	if (nilfs_checkpoint_invalid(cp))

		ret = -ENOENT;

	else

		ret = nilfs_checkpoint_snapshot(cp);

	kunmap_atomic(kaddr, KM_USER0);

	brelse(bh);

fs/nilfs2/super.c

+6 −1
Original line number Diff line number Diff line
@@ -792,10 +792,15 @@ nilfs_fill_super(struct super_block *sb, void *data, int silent, 


	if (sb->s_flags & MS_RDONLY) {

		if (nilfs_test_opt(sbi, SNAPSHOT)) {

			down_read(&nilfs->ns_segctor_sem);

			err = nilfs_cpfile_is_snapshot(nilfs->ns_cpfile,

						       sbi->s_snapshot_cno);

			if (err < 0)

			up_read(&nilfs->ns_segctor_sem);

			if (err < 0) {

				if (err == -ENOENT)

					err = -EINVAL;

				goto failed_sbi;

			}

			if (!err) {

				printk(KERN_ERR

				       "NILFS: The specified checkpoint is "