5.15-stable review patch. If anyone has any objections, please let me know.
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From: ruanmeisi ruan.meisi@zte.com.cn
commit b8bd342d50cbf606666488488f9fea374aceb2d5 upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/fuse/readdir.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-)
--- a/fs/fuse/readdir.c +++ b/fs/fuse/readdir.c @@ -243,8 +243,16 @@ retry: 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);