From: Amir Goldstein Date: Mon, 28 Feb 2011 05:53:45 +0000 (-0500) Subject: ext4: skip orphan cleanup if fs has unknown ROCOMPAT features X-Git-Tag: v2.6.39-rc1~73^2~15 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=d39195c33bb1b5fdcb0f416e8a0b34bfdb07a027;p=karo-tx-linux.git ext4: skip orphan cleanup if fs has unknown ROCOMPAT features Orphan cleanup is currently executed even if the file system has some number of unknown ROCOMPAT features, which deletes inodes and frees blocks, which could be very bad for some RO_COMPAT features, especially the SNAPSHOT feature. This patch skips the orphan cleanup if it contains readonly compatible features not known by this ext4 implementation, which would prevent the fs from being mounted (or remounted) readwrite. Signed-off-by: Amir Goldstein Signed-off-by: "Theodore Ts'o" --- diff --git a/fs/ext4/super.c b/fs/ext4/super.c index bd6e86aa82aa..9eaec22aa088 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -75,6 +75,7 @@ static void ext4_write_super(struct super_block *sb); static int ext4_freeze(struct super_block *sb); static struct dentry *ext4_mount(struct file_system_type *fs_type, int flags, const char *dev_name, void *data); +static int ext4_feature_set_ok(struct super_block *sb, int readonly); static void ext4_destroy_lazyinit_thread(void); static void ext4_unregister_li_request(struct super_block *sb); static void ext4_clear_request_list(void); @@ -2117,6 +2118,13 @@ static void ext4_orphan_cleanup(struct super_block *sb, return; } + /* Check if feature set would not allow a r/w mount */ + if (!ext4_feature_set_ok(sb, 0)) { + ext4_msg(sb, KERN_INFO, "Skipping orphan cleanup due to " + "unknown ROCOMPAT features"); + return; + } + if (EXT4_SB(sb)->s_mount_state & EXT4_ERROR_FS) { if (es->s_last_orphan) jbd_debug(1, "Errors on filesystem, "