From: Jeff Mahoney Date: Fri, 1 May 2009 16:11:12 +0000 (-0400) Subject: reiserfs: Expand i_mutex to enclose lookup_one_len X-Git-Tag: MMI-PSA29.97-13-9~28196^2~20 X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=5a6059c358d3b3004cb6b8562e3b049b1f8564f9;p=GitHub%2FMotorolaMobilityLLC%2Fkernel-slsi.git reiserfs: Expand i_mutex to enclose lookup_one_len 2.6.30-rc3 introduced some sanity checks in the VFS code to avoid NFS bugs by ensuring that lookup_one_len is always called under i_mutex. This patch expands the i_mutex locking to enclose lookup_one_len. This was always required, but not not enforced in the reiserfs code since it does locking around the xattr interactions with the xattr_sem. This is obvious enough, and it survived an overnight 50 thread ACL test. Signed-off-by: Jeff Mahoney Signed-off-by: Al Viro --- diff --git a/fs/reiserfs/xattr.c b/fs/reiserfs/xattr.c index f83f52bae390..31a3dbb120e1 100644 --- a/fs/reiserfs/xattr.c +++ b/fs/reiserfs/xattr.c @@ -120,25 +120,20 @@ static struct dentry *lookup_or_create_dir(struct dentry *parent, struct dentry *dentry; BUG_ON(!parent); + mutex_lock_nested(&parent->d_inode->i_mutex, I_MUTEX_XATTR); dentry = lookup_one_len(name, parent, strlen(name)); - if (IS_ERR(dentry)) - return dentry; - else if (!dentry->d_inode) { + if (!IS_ERR(dentry) && !dentry->d_inode) { int err = -ENODATA; - if (xattr_may_create(flags)) { - mutex_lock_nested(&parent->d_inode->i_mutex, - I_MUTEX_XATTR); + if (xattr_may_create(flags)) err = xattr_mkdir(parent->d_inode, dentry, 0700); - mutex_unlock(&parent->d_inode->i_mutex); - } if (err) { dput(dentry); dentry = ERR_PTR(err); } } - + mutex_unlock(&parent->d_inode->i_mutex); return dentry; } @@ -184,6 +179,7 @@ fill_with_dentries(void *buf, const char *name, int namelen, loff_t offset, { struct reiserfs_dentry_buf *dbuf = buf; struct dentry *dentry; + WARN_ON_ONCE(!mutex_is_locked(&dbuf->xadir->d_inode->i_mutex)); if (dbuf->count == ARRAY_SIZE(dbuf->dentries)) return -ENOSPC; @@ -349,6 +345,7 @@ static struct dentry *xattr_lookup(struct inode *inode, const char *name, if (IS_ERR(xadir)) return ERR_CAST(xadir); + mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR); xafile = lookup_one_len(name, xadir, strlen(name)); if (IS_ERR(xafile)) { err = PTR_ERR(xafile); @@ -360,18 +357,15 @@ static struct dentry *xattr_lookup(struct inode *inode, const char *name, if (!xafile->d_inode) { err = -ENODATA; - if (xattr_may_create(flags)) { - mutex_lock_nested(&xadir->d_inode->i_mutex, - I_MUTEX_XATTR); + if (xattr_may_create(flags)) err = xattr_create(xadir->d_inode, xafile, 0700|S_IFREG); - mutex_unlock(&xadir->d_inode->i_mutex); - } } if (err) dput(xafile); out: + mutex_unlock(&xadir->d_inode->i_mutex); dput(xadir); if (err) return ERR_PTR(err); @@ -435,6 +429,7 @@ static int lookup_and_delete_xattr(struct inode *inode, const char *name) if (IS_ERR(xadir)) return PTR_ERR(xadir); + mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR); dentry = lookup_one_len(name, xadir, strlen(name)); if (IS_ERR(dentry)) { err = PTR_ERR(dentry); @@ -442,14 +437,13 @@ static int lookup_and_delete_xattr(struct inode *inode, const char *name) } if (dentry->d_inode) { - mutex_lock_nested(&xadir->d_inode->i_mutex, I_MUTEX_XATTR); err = xattr_unlink(xadir->d_inode, dentry); - mutex_unlock(&xadir->d_inode->i_mutex); update_ctime(inode); } dput(dentry); out_dput: + mutex_unlock(&xadir->d_inode->i_mutex); dput(xadir); return err; } @@ -906,9 +900,9 @@ static int create_privroot(struct dentry *dentry) { int err; struct inode *inode = dentry->d_parent->d_inode; - mutex_lock_nested(&inode->i_mutex, I_MUTEX_XATTR); + WARN_ON_ONCE(!mutex_is_locked(&inode->i_mutex)); + err = xattr_mkdir(inode, dentry, 0700); - mutex_unlock(&inode->i_mutex); if (err) { dput(dentry); dentry = NULL; @@ -980,6 +974,7 @@ int reiserfs_xattr_init(struct super_block *s, int mount_flags) /* If we don't have the privroot located yet - go find it */ if (!REISERFS_SB(s)->priv_root) { struct dentry *dentry; + mutex_lock_nested(&s->s_root->d_inode->i_mutex, I_MUTEX_CHILD); dentry = lookup_one_len(PRIVROOT_NAME, s->s_root, strlen(PRIVROOT_NAME)); if (!IS_ERR(dentry)) { @@ -993,6 +988,7 @@ int reiserfs_xattr_init(struct super_block *s, int mount_flags) } } else err = PTR_ERR(dentry); + mutex_unlock(&s->s_root->d_inode->i_mutex); if (!err && dentry) { s->s_root->d_op = &xattr_lookup_poison_ops;