From c5ca48aabe8b11674bf1102abe52d17ecc053f9c Mon Sep 17 00:00:00 2001 From: Ryusuke Konishi Date: Thu, 22 Jul 2010 03:22:20 +0900 Subject: [PATCH] nilfs2: reject incompatible filesystem This forces nilfs to check compatibility of feature flags so as to reject a filesystem with unknown features when it mounts or remounts the filesystem. Signed-off-by: Ryusuke Konishi --- fs/nilfs2/nilfs.h | 2 ++ fs/nilfs2/super.c | 39 +++++++++++++++++++++++++++++++++++++++ fs/nilfs2/the_nilfs.c | 20 ++++++++++++++++++++ 3 files changed, 61 insertions(+) diff --git a/fs/nilfs2/nilfs.h b/fs/nilfs2/nilfs.h index cfedc48..0842d77 100644 --- a/fs/nilfs2/nilfs.h +++ b/fs/nilfs2/nilfs.h @@ -275,6 +275,8 @@ extern struct nilfs_super_block * nilfs_read_super_block(struct super_block *, u64, int, struct buffer_head **); extern int nilfs_store_magic_and_option(struct super_block *, struct nilfs_super_block *, char *); +extern int nilfs_check_feature_compatibility(struct super_block *, + struct nilfs_super_block *); extern void nilfs_set_log_cursor(struct nilfs_super_block *, struct the_nilfs *); extern struct nilfs_super_block **nilfs_prepare_super(struct nilfs_sb_info *, diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c index 1644573..26078b3 100644 --- a/fs/nilfs2/super.c +++ b/fs/nilfs2/super.c @@ -790,6 +790,30 @@ int nilfs_store_magic_and_option(struct super_block *sb, return !parse_options(data, sb, 0) ? -EINVAL : 0 ; } +int nilfs_check_feature_compatibility(struct super_block *sb, + struct nilfs_super_block *sbp) +{ + __u64 features; + + features = le64_to_cpu(sbp->s_feature_incompat) & + ~NILFS_FEATURE_INCOMPAT_SUPP; + if (features) { + printk(KERN_ERR "NILFS: couldn't mount because of unsupported " + "optional features (%llx)\n", + (unsigned long long)features); + return -EINVAL; + } + features = le64_to_cpu(sbp->s_feature_compat_ro) & + ~NILFS_FEATURE_COMPAT_RO_SUPP; + if (!(sb->s_flags & MS_RDONLY) && features) { + printk(KERN_ERR "NILFS: couldn't mount RDWR because of " + "unsupported optional features (%llx)\n", + (unsigned long long)features); + return -EINVAL; + } + return 0; +} + /** * nilfs_fill_super() - initialize a super block instance * @sb: super_block @@ -984,11 +1008,26 @@ static int nilfs_remount(struct super_block *sb, int *flags, char *data) nilfs_cleanup_super(sbi); up_write(&nilfs->ns_sem); } else { + __u64 features; + /* * Mounting a RDONLY partition read-write, so reread and * store the current valid flag. (It may have been changed * by fsck since we originally mounted the partition.) */ + down_read(&nilfs->ns_sem); + features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) & + ~NILFS_FEATURE_COMPAT_RO_SUPP; + up_read(&nilfs->ns_sem); + if (features) { + printk(KERN_WARNING "NILFS (device %s): couldn't " + "remount RDWR because of unsupported optional " + "features (%llx)\n", + sb->s_id, (unsigned long long)features); + err = -EROFS; + goto restore_opts; + } + sb->s_flags &= ~MS_RDONLY; err = nilfs_attach_segment_constructor(sbi); diff --git a/fs/nilfs2/the_nilfs.c b/fs/nilfs2/the_nilfs.c index f2efc8c..da67b56 100644 --- a/fs/nilfs2/the_nilfs.c +++ b/fs/nilfs2/the_nilfs.c @@ -385,11 +385,23 @@ int load_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi) goto skip_recovery; if (s_flags & MS_RDONLY) { + __u64 features; + if (nilfs_test_opt(sbi, NORECOVERY)) { printk(KERN_INFO "NILFS: norecovery option specified. " "skipping roll-forward recovery\n"); goto skip_recovery; } + features = le64_to_cpu(nilfs->ns_sbp[0]->s_feature_compat_ro) & + ~NILFS_FEATURE_COMPAT_RO_SUPP; + if (features) { + printk(KERN_ERR "NILFS: couldn't proceed with " + "recovery because of unsupported optional " + "features (%llx)\n", + (unsigned long long)features); + err = -EROFS; + goto failed_unload; + } if (really_read_only) { printk(KERN_ERR "NILFS: write access " "unavailable, cannot proceed.\n"); @@ -644,6 +656,10 @@ int init_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi, char *data) if (err) goto out; + err = nilfs_check_feature_compatibility(sb, sbp); + if (err) + goto out; + blocksize = BLOCK_SIZE << le32_to_cpu(sbp->s_log_block_size); if (sb->s_blocksize != blocksize && !sb_set_blocksize(sb, blocksize)) { @@ -669,6 +685,10 @@ int init_nilfs(struct the_nilfs *nilfs, struct nilfs_sb_info *sbi, char *data) if (err) goto failed_sbh; + err = nilfs_check_feature_compatibility(sb, sbp); + if (err) + goto failed_sbh; + blocksize = BLOCK_SIZE << le32_to_cpu(sbp->s_log_block_size); if (sb->s_blocksize != blocksize) { int hw_blocksize = bdev_logical_block_size(sb->s_bdev); -- 2.7.4