From c1892c37769cf89c7e7ba57528ae2ccb5d153c9b Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 3 Aug 2016 13:44:27 +0200 Subject: vfs: fix deadlock in file_remove_privs() on overlayfs file_remove_privs() is called with inode lock on file_inode(), which proceeds to calling notify_change() on file->f_path.dentry. Which triggers the WARN_ON_ONCE(!inode_is_locked(inode)) in addition to deadlocking later when ovl_setattr tries to lock the underlying inode again. Fix this mess by not mixing the layers, but doing everything on underlying dentry/inode. Signed-off-by: Miklos Szeredi Fixes: 07a2daab49c5 ("ovl: Copy up underlying inode's ->i_mode to overlay inode") Cc: --- fs/inode.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'fs/inode.c') diff --git a/fs/inode.c b/fs/inode.c index 4ccbc21b30ce..68db39050446 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -1740,8 +1740,8 @@ static int __remove_privs(struct dentry *dentry, int kill) */ int file_remove_privs(struct file *file) { - struct dentry *dentry = file->f_path.dentry; - struct inode *inode = d_inode(dentry); + struct dentry *dentry = file_dentry(file); + struct inode *inode = file_inode(file); int kill; int error = 0; @@ -1749,7 +1749,7 @@ int file_remove_privs(struct file *file) if (IS_NOSEC(inode)) return 0; - kill = file_needs_remove_privs(file); + kill = dentry_needs_remove_privs(dentry); if (kill < 0) return kill; if (kill) -- cgit v1.2.3 From f0fce87c36aec5c4a895c78b76396f5727047b93 Mon Sep 17 00:00:00 2001 From: Miklos Szeredi Date: Wed, 3 Aug 2016 13:44:27 +0200 Subject: vfs: make dentry_needs_remove_privs() internal Only used by the vfs. Signed-off-by: Miklos Szeredi --- fs/inode.c | 1 - 1 file changed, 1 deletion(-) (limited to 'fs/inode.c') diff --git a/fs/inode.c b/fs/inode.c index 68db39050446..2029357fcf97 100644 --- a/fs/inode.c +++ b/fs/inode.c @@ -1720,7 +1720,6 @@ int dentry_needs_remove_privs(struct dentry *dentry) mask |= ATTR_KILL_PRIV; return mask; } -EXPORT_SYMBOL(dentry_needs_remove_privs); static int __remove_privs(struct dentry *dentry, int kill) { -- cgit v1.2.3