Prev: [027/140] net/core: neighbour update Oops
Next: [037/140] hostap: Protect against initialization interrupt
From: Greg KH on 30 Jul 2010 15:00
2.6.32-stable review patch. If anyone has any objections, please let us know.

------------------

commit f39490bcd1691d65dc33689222a12e1fc13dd824 upstream (as of v2.6.33-git11)

Set i_nlink to zero for temporary inode from very beginning.
otherwise we may fail to start new journal handle and this
inode will be unreferenced but with i_nlink == 1
Since we hold inode reference it can not be pruned.

Also add missed journal_start retval check.

Signed-off-by: Dmitry Monakhov <dmonakhov(a)openvz.org>
Signed-off-by: "Theodore Ts'o" <tytso(a)mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh(a)suse.de>
---
fs/ext4/migrate.c | 29 ++++++++++++++---------------
1 file changed, 14 insertions(+), 15 deletions(-)

--- a/fs/ext4/migrate.c
+++ b/fs/ext4/migrate.c
@@ -494,14 +494,10 @@ int ext4_ext_migrate(struct inode *inode
}
i_size_write(tmp_inode, i_size_read(inode));
/*
- * We don't want the inode to be reclaimed
- * if we got interrupted in between. We have
- * this tmp inode carrying reference to the
- * data blocks of the original file. We set
- * the i_nlink to zero at the last stage after
- * switching the original file to extent format
+ * Set the i_nlink to zero so it will be deleted later
+ * when we drop inode reference.
*/
- tmp_inode->i_nlink = 1;
+ tmp_inode->i_nlink = 0;

ext4_ext_tree_init(handle, tmp_inode);
ext4_orphan_add(handle, tmp_inode);
@@ -528,6 +524,16 @@ int ext4_ext_migrate(struct inode *inode
up_read((&EXT4_I(inode)->i_data_sem));

handle = ext4_journal_start(inode, 1);
+ if (IS_ERR(handle)) {
+ /*
+ * It is impossible to update on-disk structures without
+ * a handle, so just rollback in-core changes and live other
+ * work to orphan_list_cleanup()
+ */
+ ext4_orphan_del(NULL, tmp_inode);
+ retval = PTR_ERR(handle);
+ goto out;
+ }

ei = EXT4_I(inode);
i_data = ei->i_data;
@@ -609,15 +615,8 @@ err_out:

/* Reset the extent details */
ext4_ext_tree_init(handle, tmp_inode);
-
- /*
- * Set the i_nlink to zero so that
- * generic_drop_inode really deletes the
- * inode
- */
- tmp_inode->i_nlink = 0;
-
ext4_journal_stop(handle);
+out:
unlock_new_inode(tmp_inode);
iput(tmp_inode);



--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo(a)vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
 | 
Pages: 1
Prev: [027/140] net/core: neighbour update Oops
Next: [037/140] hostap: Protect against initialization interrupt