From: Trond Myklebust trond.myklebust@hammerspace.com
mainline inclusion from mainline-v5.12-rc3 commit 82e7ca1334ab16e2e04fafded1cab9dfcdc11b40 category: bugfix bugzilla: NA CVE: NA
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There should be no reason to expect the directory permissions to change just because the directory contents changed or a negative lookup timed out. So let's avoid doing a full call to nfs_mark_for_revalidate() in that case. Furthermore, if this is a negative dentry, and we haven't actually done a new lookup, then we have no reason yet to believe the directory has changed at all. So let's remove the gratuitous directory inode invalidation altogether when called from nfs_lookup_revalidate_negative().
Reported-by: Geert Jansen gerardu@amazon.com Fixes: 5ceb9d7fdaaf ("NFS: Refactor nfs_lookup_revalidate()") Signed-off-by: Trond Myklebust trond.myklebust@hammerspace.com Signed-off-by: Anna Schumaker Anna.Schumaker@Netapp.com Signed-off-by: Zhang Xiaoxu zhangxiaoxu5@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Signed-off-by: Yang Yingliang yangyingliang@huawei.com --- fs/nfs/dir.c | 20 +++++++++++++++++--- 1 file changed, 17 insertions(+), 3 deletions(-)
diff --git a/fs/nfs/dir.c b/fs/nfs/dir.c index 3908ff8672af1..a4655edf43630 100644 --- a/fs/nfs/dir.c +++ b/fs/nfs/dir.c @@ -1072,6 +1072,15 @@ int nfs_lookup_verify_inode(struct inode *inode, unsigned int flags) goto out; }
+static void nfs_mark_dir_for_revalidate(struct inode *inode) +{ + struct nfs_inode *nfsi = NFS_I(inode); + + spin_lock(&inode->i_lock); + nfsi->cache_validity |= NFS_INO_REVAL_PAGECACHE; + spin_unlock(&inode->i_lock); +} + /* * We judge how long we want to trust negative * dentries by looking at the parent inode mtime. @@ -1106,7 +1115,6 @@ nfs_lookup_revalidate_done(struct inode *dir, struct dentry *dentry, __func__, dentry); return 1; case 0: - nfs_mark_for_revalidate(dir); if (inode && S_ISDIR(inode->i_mode)) { /* Purge readdir caches. */ nfs_zap_caches(inode); @@ -1187,6 +1195,13 @@ nfs_lookup_revalidate_dentry(struct inode *dir, struct dentry *dentry, nfs_free_fattr(fattr); nfs_free_fhandle(fhandle); nfs4_label_free(label); + + /* + * If the lookup failed despite the dentry change attribute being + * a match, then we should revalidate the directory cache. + */ + if (!ret && nfs_verify_change_attribute(dir, dentry->d_time)) + nfs_mark_dir_for_revalidate(dir); return nfs_lookup_revalidate_done(dir, dentry, inode, ret); }
@@ -1229,7 +1244,7 @@ nfs_do_lookup_revalidate(struct inode *dir, struct dentry *dentry, error = nfs_lookup_verify_inode(inode, flags); if (error) { if (error == -ESTALE) - nfs_zap_caches(dir); + nfs_mark_dir_for_revalidate(dir); goto out_bad; } nfs_advise_use_readdirplus(dir); @@ -1724,7 +1739,6 @@ nfs_add_or_obtain(struct dentry *dentry, struct nfs_fh *fhandle, dput(parent); return d; out_error: - nfs_mark_for_revalidate(dir); d = ERR_PTR(error); goto out; }