The patch below does not apply to the 4.19-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

To reproduce the conflict and resubmit, you may use the following commands:

git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-4.19.y git checkout FETCH_HEAD git cherry-pick -x b8bd342d50cbf606666488488f9fea374aceb2d5 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to 'stable@vger.kernel.org' --in-reply-to '2023091601-spotted-untie-0ba4@gregkh' --subject-prefix 'PATCH 4.19.y' HEAD^..

Possible dependencies:

b8bd342d50cb ("fuse: nlookup missing decrement in fuse_direntplus_link") d123d8e1833c ("fuse: split out readdir.c")

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From b8bd342d50cbf606666488488f9fea374aceb2d5 Mon Sep 17 00:00:00 2001 From: ruanmeisi ruan.meisi@zte.com.cn Date: Tue, 25 Apr 2023 19:13:54 +0800 Subject: [PATCH] fuse: nlookup missing decrement in fuse_direntplus_link

During our debugging of glusterfs, we found an Assertion failed error: inode_lookup >= nlookup, which was caused by the nlookup value in the kernel being greater than that in the FUSE file system.

The issue was introduced by fuse_direntplus_link, where in the function, fuse_iget increments nlookup, and if d_splice_alias returns failure, fuse_direntplus_link returns failure without decrementing nlookup https://github.com/gluster/glusterfs/pull/4081

Signed-off-by: ruanmeisi ruan.meisi@zte.com.cn Fixes: 0b05b18381ee ("fuse: implement NFS-like readdirplus support") Cc: stable@vger.kernel.org # v3.9 Signed-off-by: Miklos Szeredi mszeredi@redhat.com

diff --git a/fs/fuse/readdir.c b/fs/fuse/readdir.c index dc603479b30e..b3d498163f97 100644 --- a/fs/fuse/readdir.c +++ b/fs/fuse/readdir.c @@ -243,8 +243,16 @@ static int fuse_direntplus_link(struct file *file, dput(dentry); dentry = alias; } - if (IS_ERR(dentry)) + if (IS_ERR(dentry)) { + if (!IS_ERR(inode)) { + struct fuse_inode *fi = get_fuse_inode(inode); + + spin_lock(&fi->lock); + fi->nlookup--; + spin_unlock(&fi->lock); + } return PTR_ERR(dentry); + } } if (fc->readdirplus_auto) set_bit(FUSE_I_INIT_RDPLUS, &get_fuse_inode(inode)->state);