From 48f35b7b7367c6c2594f9c209ee2e1362519a899 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 12 Apr 2016 00:37:59 -0400 Subject: [PATCH] configfs_detach_prep(): make sure that wait_mutex won't go away grab a reference to dentry we'd got the sucker from, and return that dentry via *wait, rather than just returning the address of ->i_mutex. Signed-off-by: Al Viro --- fs/configfs/dir.c | 17 +++++++++-------- 1 file changed, 9 insertions(+), 8 deletions(-) diff --git a/fs/configfs/dir.c b/fs/configfs/dir.c index ea59c891fc53..48929c408e04 100644 --- a/fs/configfs/dir.c +++ b/fs/configfs/dir.c @@ -494,7 +494,7 @@ out: * If there is an error, the caller will reset the flags via * configfs_detach_rollback(). */ -static int configfs_detach_prep(struct dentry *dentry, struct mutex **wait_mutex) +static int configfs_detach_prep(struct dentry *dentry, struct dentry **wait) { struct configfs_dirent *parent_sd = dentry->d_fsdata; struct configfs_dirent *sd; @@ -515,8 +515,8 @@ static int configfs_detach_prep(struct dentry *dentry, struct mutex **wait_mutex if (sd->s_type & CONFIGFS_USET_DEFAULT) { /* Abort if racing with mkdir() */ if (sd->s_type & CONFIGFS_USET_IN_MKDIR) { - if (wait_mutex) - *wait_mutex = &d_inode(sd->s_dentry)->i_mutex; + if (wait) + *wait= dget(sd->s_dentry); return -EAGAIN; } @@ -524,7 +524,7 @@ static int configfs_detach_prep(struct dentry *dentry, struct mutex **wait_mutex * Yup, recursive. If there's a problem, blame * deep nesting of default_groups */ - ret = configfs_detach_prep(sd->s_dentry, wait_mutex); + ret = configfs_detach_prep(sd->s_dentry, wait); if (!ret) continue; } else @@ -1458,7 +1458,7 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry) * the new link is temporarily attached */ do { - struct mutex *wait_mutex; + struct dentry *wait; mutex_lock(&configfs_symlink_mutex); spin_lock(&configfs_dirent_lock); @@ -1469,7 +1469,7 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry) */ ret = sd->s_dependent_count ? -EBUSY : 0; if (!ret) { - ret = configfs_detach_prep(dentry, &wait_mutex); + ret = configfs_detach_prep(dentry, &wait); if (ret) configfs_detach_rollback(dentry); } @@ -1483,8 +1483,9 @@ static int configfs_rmdir(struct inode *dir, struct dentry *dentry) } /* Wait until the racing operation terminates */ - mutex_lock(wait_mutex); - mutex_unlock(wait_mutex); + inode_lock(d_inode(wait)); + inode_unlock(d_inode(wait)); + dput(wait); } } while (ret == -EAGAIN); -- 2.30.2