ext4: handle corrupted orphan list at mount

If the orphan node list includes valid, untruncatable nodes with nlink > 0
the ext4_orphan_cleanup loop which attempts to delete them will not do so,
causing it to loop forever. Fix by checking for such nodes in the
ext4_orphan_get function.

This patch fixes the second case (image hdb.20000009.softlockup.gz)
reported in http://bugzilla.kernel.org/show_bug.cgi?id=10882.

Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/fs/ext4/ext4.h b/fs/ext4/ext4.h
index 8158083f7ac0a04673529125fe2aa58babd4cb8d..f7a0758f4689bd0809a6f1986ecb06d915f59985 100644 (file)
--- a/fs/ext4/ext4.h
+++ b/fs/ext4/ext4.h
@@ -1039,6 +1039,7 @@ extern void ext4_discard_reservation (struct inode *);
 extern void ext4_dirty_inode(struct inode *);
 extern int ext4_change_inode_journal_flag(struct inode *, int);
 extern int ext4_get_inode_loc(struct inode *, struct ext4_iloc *);
+extern int ext4_can_truncate(struct inode *inode);
 extern void ext4_truncate (struct inode *);
 extern void ext4_set_inode_flags(struct inode *);
 extern void ext4_get_inode_flags(struct ext4_inode_info *);

diff --git a/fs/ext4/ialloc.c b/fs/ext4/ialloc.c
index c6efbab0c80187942dfcedc867d514c76badcefc..11cafe14aa2725482d6ef592e9eb6475af6a8bfb 100644 (file)
--- a/fs/ext4/ialloc.c
+++ b/fs/ext4/ialloc.c
@@ -817,6 +817,14 @@ struct inode *ext4_orphan_get(struct super_block *sb, unsigned long ino)
        if (IS_ERR(inode))
                goto iget_failed;
 
+       /*
+        * If the orphans has i_nlinks > 0 then it should be able to be
+        * truncated, otherwise it won't be removed from the orphan list
+        * during processing and an infinite loop will result.
+        */
+       if (inode->i_nlink && !ext4_can_truncate(inode))
+               goto bad_orphan;
+
        if (NEXT_ORPHAN(inode) > max_ino)
                goto bad_orphan;
        brelse(bitmap_bh);
@@ -838,6 +846,7 @@ bad_orphan:
                printk(KERN_NOTICE "NEXT_ORPHAN(inode)=%u\n",
                       NEXT_ORPHAN(inode));
                printk(KERN_NOTICE "max_ino=%lu\n", max_ino);
+               printk(KERN_NOTICE "i_nlink=%u\n", inode->i_nlink);
                /* Avoid freeing blocks if we got a bad deleted inode */
                if (inode->i_nlink == 0)
                        inode->i_blocks = 0;

diff --git a/fs/ext4/inode.c b/fs/ext4/inode.c
index 8d9707746413d90bc5bf019ea6e2dacad91842c2..269763b66361129f7d2a4872fbda07b8d8fe5761 100644 (file)
--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -2305,6 +2305,19 @@ static void ext4_free_branches(handle_t *handle, struct inode *inode,
        }
 }
 
+int ext4_can_truncate(struct inode *inode)
+{
+       if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+               return 0;
+       if (S_ISREG(inode->i_mode))
+               return 1;
+       if (S_ISDIR(inode->i_mode))
+               return 1;
+       if (S_ISLNK(inode->i_mode))
+               return !ext4_inode_is_fast_symlink(inode);
+       return 0;
+}
+
 /*
  * ext4_truncate()
  *
@@ -2349,12 +2362,7 @@ void ext4_truncate(struct inode *inode)
        unsigned blocksize = inode->i_sb->s_blocksize;
        struct page *page;
 
-       if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode) ||
-           S_ISLNK(inode->i_mode)))
-               return;
-       if (ext4_inode_is_fast_symlink(inode))
-               return;
-       if (IS_APPEND(inode) || IS_IMMUTABLE(inode))
+       if (!ext4_can_truncate(inode))
                return;
 
        /*