nilfs2: Add more safeguard routines and protections in mount process, which also makes nilsf2 report consistency error messages when checkpoint number is invalid.
Signed-off-by: Zhu Yanhai <[email protected]> --- fs/nilfs2/cpfile.c | 11 ++++++++--- fs/nilfs2/super.c | 7 ++++++- 2 files changed, 14 insertions(+), 4 deletions(-) diff --git a/fs/nilfs2/cpfile.c b/fs/nilfs2/cpfile.c index aec942c..1c6cfb5 100644 --- a/fs/nilfs2/cpfile.c +++ b/fs/nilfs2/cpfile.c @@ -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); @@ -824,7 +826,10 @@ 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); - ret = nilfs_checkpoint_snapshot(cp); + if (nilfs_checkpoint_invalid(cp)) + ret = -ENOENT; + else + ret = nilfs_checkpoint_snapshot(cp); kunmap_atomic(kaddr, KM_USER0); brelse(bh); diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c index 8e2ec43..b2ad589 100644 --- a/fs/nilfs2/super.c +++ b/fs/nilfs2/super.c @@ -814,10 +814,15 @@ 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 " -- 1.6.2.2 _______________________________________________ users mailing list [email protected] https://www.nilfs.org/mailman/listinfo/users
