ext{3,4}: Fix potential race when setversion ioctl updates inode

The EXT{3,4}_IOC_SETVERSION ioctl() updates i_ctime and i_generation
without i_mutex. This can lead to a race with the other operations that
update i_ctime. This is not a big issue but let's make the ioctl consistent
with how we handle e.g. other timestamp updates and use i_mutex to protect
inode changes.

Signed-off-by: Djalal Harouni <tixxdz@opendz.org>
Signed-off-by: Jan Kara <jack@suse.cz>
This commit is contained in:
Djalal Harouni 2012-01-03 02:31:52 +01:00 committed by Jan Kara
parent 853a0c25ba
commit 6c2155b9cc
2 changed files with 10 additions and 2 deletions

View File

@ -134,10 +134,11 @@ long ext3_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
goto setversion_out;
}
mutex_lock(&inode->i_mutex);
handle = ext3_journal_start(inode, 1);
if (IS_ERR(handle)) {
err = PTR_ERR(handle);
goto setversion_out;
goto unlock_out;
}
err = ext3_reserve_inode_write(handle, inode, &iloc);
if (err == 0) {
@ -146,6 +147,9 @@ long ext3_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
err = ext3_mark_iloc_dirty(handle, inode, &iloc);
}
ext3_journal_stop(handle);
unlock_out:
mutex_unlock(&inode->i_mutex);
setversion_out:
mnt_drop_write(filp->f_path.mnt);
return err;

View File

@ -158,10 +158,11 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
goto setversion_out;
}
mutex_lock(&inode->i_mutex);
handle = ext4_journal_start(inode, 1);
if (IS_ERR(handle)) {
err = PTR_ERR(handle);
goto setversion_out;
goto unlock_out;
}
err = ext4_reserve_inode_write(handle, inode, &iloc);
if (err == 0) {
@ -170,6 +171,9 @@ long ext4_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
err = ext4_mark_iloc_dirty(handle, inode, &iloc);
}
ext4_journal_stop(handle);
unlock_out:
mutex_unlock(&inode->i_mutex);
setversion_out:
mnt_drop_write(filp->f_path.mnt);
return err;