From 74871791ffa9562d43567c5ff2ae93def3f39f65 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Mon, 25 Mar 2024 09:34:36 +0100 Subject: ntfs3: serve as alias for the legacy ntfs driver Johan Hovold reported that removing the legacy ntfs driver broke boot for him since his fstab uses the legacy ntfs driver to access firmware from the original Windows partition. Use ntfs3 as an alias for legacy ntfs if CONFIG_NTFS_FS is selected. This is similar to how ext3 is treated. Link: https://lore.kernel.org/r/Zf2zPf5TO5oYt3I3@hovoldconsulting.com Link: https://lore.kernel.org/r/20240325-hinkriegen-zuziehen-d7e2c490427a@brauner Fixes: 7ffa8f3d3023 ("fs: Remove NTFS classic") Tested-by: Johan Hovold Cc: Matthew Wilcox (Oracle) Cc: Johan Hovold Signed-off-by: Christian Brauner --- fs/ntfs3/super.c | 31 +++++++++++++++++++++++++++++++ 1 file changed, 31 insertions(+) (limited to 'fs/ntfs3/super.c') diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c index 9df7c20d066f..8d2e51bae2cb 100644 --- a/fs/ntfs3/super.c +++ b/fs/ntfs3/super.c @@ -1798,6 +1798,35 @@ static struct file_system_type ntfs_fs_type = { .kill_sb = ntfs3_kill_sb, .fs_flags = FS_REQUIRES_DEV | FS_ALLOW_IDMAP, }; + +#if IS_ENABLED(CONFIG_NTFS_FS) +static struct file_system_type ntfs_legacy_fs_type = { + .owner = THIS_MODULE, + .name = "ntfs", + .init_fs_context = ntfs_init_fs_context, + .parameters = ntfs_fs_parameters, + .kill_sb = ntfs3_kill_sb, + .fs_flags = FS_REQUIRES_DEV | FS_ALLOW_IDMAP, +}; +MODULE_ALIAS_FS("ntfs"); + +static inline void register_as_ntfs_legacy(void) +{ + int err = register_filesystem(&ntfs_legacy_fs_type); + if (err) + pr_warn("ntfs3: Failed to register legacy ntfs filesystem driver: %d\n", err); +} + +static inline void unregister_as_ntfs_legacy(void) +{ + unregister_filesystem(&ntfs_legacy_fs_type); +} +#else +static inline void register_as_ntfs_legacy(void) {} +static inline void unregister_as_ntfs_legacy(void) {} +#endif + + // clang-format on static int __init init_ntfs_fs(void) @@ -1832,6 +1861,7 @@ static int __init init_ntfs_fs(void) goto out1; } + register_as_ntfs_legacy(); err = register_filesystem(&ntfs_fs_type); if (err) goto out; @@ -1849,6 +1879,7 @@ static void __exit exit_ntfs_fs(void) rcu_barrier(); kmem_cache_destroy(ntfs_inode_cachep); unregister_filesystem(&ntfs_fs_type); + unregister_as_ntfs_legacy(); ntfs3_exit_bitmap(); #ifdef CONFIG_PROC_FS -- cgit v1.2.3 From d55f90e9b243faa5bcd5c8a323a8f43040500106 Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Tue, 16 Apr 2024 12:08:51 +0200 Subject: ntfs3: enforce read-only when used as legacy ntfs driver Ensure that ntfs3 is mounted read-only when it is used to provide the legacy ntfs driver. Signed-off-by: Christian Brauner --- fs/ntfs3/ntfs_fs.h | 2 ++ fs/ntfs3/super.c | 36 ++++++++++++++++++++++++++++++++---- 2 files changed, 34 insertions(+), 4 deletions(-) (limited to 'fs/ntfs3/super.c') diff --git a/fs/ntfs3/ntfs_fs.h b/fs/ntfs3/ntfs_fs.h index 79356fd29a14..184c8bc76b92 100644 --- a/fs/ntfs3/ntfs_fs.h +++ b/fs/ntfs3/ntfs_fs.h @@ -1154,4 +1154,6 @@ static inline void le64_sub_cpu(__le64 *var, u64 val) *var = cpu_to_le64(le64_to_cpu(*var) - val); } +bool is_legacy_ntfs(struct super_block *sb); + #endif /* _LINUX_NTFS3_NTFS_FS_H */ diff --git a/fs/ntfs3/super.c b/fs/ntfs3/super.c index 8d2e51bae2cb..b26d95a8d327 100644 --- a/fs/ntfs3/super.c +++ b/fs/ntfs3/super.c @@ -408,6 +408,12 @@ static int ntfs_fs_reconfigure(struct fs_context *fc) struct ntfs_mount_options *new_opts = fc->fs_private; int ro_rw; + /* If ntfs3 is used as legacy ntfs enforce read-only mode. */ + if (is_legacy_ntfs(sb)) { + fc->sb_flags |= SB_RDONLY; + goto out; + } + ro_rw = sb_rdonly(sb) && !(fc->sb_flags & SB_RDONLY); if (ro_rw && (sbi->flags & NTFS_FLAGS_NEED_REPLAY)) { errorf(fc, @@ -427,8 +433,6 @@ static int ntfs_fs_reconfigure(struct fs_context *fc) fc, "ntfs3: Cannot use different iocharset when remounting!"); - sync_filesystem(sb); - if (ro_rw && (sbi->volume.flags & VOLUME_FLAG_DIRTY) && !new_opts->force) { errorf(fc, @@ -436,6 +440,8 @@ static int ntfs_fs_reconfigure(struct fs_context *fc) return -EINVAL; } +out: + sync_filesystem(sb); swap(sbi->options, fc->fs_private); return 0; @@ -1613,6 +1619,8 @@ load_root: } #endif + if (is_legacy_ntfs(sb)) + sb->s_flags |= SB_RDONLY; return 0; put_inode_out: @@ -1730,7 +1738,7 @@ static const struct fs_context_operations ntfs_context_ops = { * This will called when mount/remount. We will first initialize * options so that if remount we can use just that. */ -static int ntfs_init_fs_context(struct fs_context *fc) +static int __ntfs_init_fs_context(struct fs_context *fc) { struct ntfs_mount_options *opts; struct ntfs_sb_info *sbi; @@ -1778,6 +1786,11 @@ free_opts: return -ENOMEM; } +static int ntfs_init_fs_context(struct fs_context *fc) +{ + return __ntfs_init_fs_context(fc); +} + static void ntfs3_kill_sb(struct super_block *sb) { struct ntfs_sb_info *sbi = sb->s_fs_info; @@ -1800,10 +1813,20 @@ static struct file_system_type ntfs_fs_type = { }; #if IS_ENABLED(CONFIG_NTFS_FS) +static int ntfs_legacy_init_fs_context(struct fs_context *fc) +{ + int ret; + + ret = __ntfs_init_fs_context(fc); + /* If ntfs3 is used as legacy ntfs enforce read-only mode. */ + fc->sb_flags |= SB_RDONLY; + return ret; +} + static struct file_system_type ntfs_legacy_fs_type = { .owner = THIS_MODULE, .name = "ntfs", - .init_fs_context = ntfs_init_fs_context, + .init_fs_context = ntfs_legacy_init_fs_context, .parameters = ntfs_fs_parameters, .kill_sb = ntfs3_kill_sb, .fs_flags = FS_REQUIRES_DEV | FS_ALLOW_IDMAP, @@ -1821,9 +1844,14 @@ static inline void unregister_as_ntfs_legacy(void) { unregister_filesystem(&ntfs_legacy_fs_type); } +bool is_legacy_ntfs(struct super_block *sb) +{ + return sb->s_type == &ntfs_legacy_fs_type; +} #else static inline void register_as_ntfs_legacy(void) {} static inline void unregister_as_ntfs_legacy(void) {} +bool is_legacy_ntfs(struct super_block *sb) { return false; } #endif -- cgit v1.2.3