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[193.226.214.118]) by smtp.gmail.com with ESMTPSA id a640c23a62f3a-a9a912d5fcesm358874066b.26.2024.10.22.08.55.14 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 22 Oct 2024 08:55:14 -0700 (PDT) From: Miklos Szeredi To: linux-unionfs@vger.kernel.org Cc: Amir Goldstein , Al Viro , linux-fsdevel@vger.kernel.org Subject: [PATCH] ovl: clarify dget/dput in ovl_cleanup() Date: Tue, 22 Oct 2024 17:55:11 +0200 Message-ID: <20241022155513.303860-1-mszeredi@redhat.com> X-Mailer: git-send-email 2.47.0 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add a comment explaining the reason for the seemingly pointless extra reference. Suggested-by: Al Viro Signed-off-by: Miklos Szeredi --- fs/overlayfs/dir.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/fs/overlayfs/dir.c b/fs/overlayfs/dir.c index ab65e98a1def..9e97f7dffd90 100644 --- a/fs/overlayfs/dir.c +++ b/fs/overlayfs/dir.c @@ -28,6 +28,10 @@ int ovl_cleanup(struct ovl_fs *ofs, struct inode *wdir, struct dentry *wdentry) { int err; + /* + * Cached negative upper dentries are generally not useful, so grab a + * ref to the victim to keep it from turning negative. + */ dget(wdentry); if (d_is_dir(wdentry)) err = ovl_do_rmdir(ofs, wdir, wdentry);