linux-ext4 - [PATCH v2 7/7] f2fs: Enable negative dentries on case-insensitive lookup

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Date:   Fri,  3 Feb 2023 18:00:39 -0300
From:   Gabriel Krisman Bertazi <krisman@...e.de>
To:     viro@...iv.linux.org.uk, tytso@....edu, jaegeuk@...nel.org,
        ebiggers@...nel.org, jack@...e.cz
Cc:     linux-fsdevel@...r.kernel.org, linux-ext4@...r.kernel.org,
        linux-f2fs-devel@...ts.sourceforge.net,
        Gabriel Krisman Bertazi <krisman@...labora.com>
Subject: [PATCH v2 7/7] f2fs: Enable negative dentries on case-insensitive lookup

From: Gabriel Krisman Bertazi <krisman@...labora.com>

Instead of invalidating negative dentries during case-insensitive
lookups, mark them as such and let them be added to the dcache.
d_ci_revalidate is able to properly filter them out if necessary based
on the dentry casefold flag.

Signed-off-by: Gabriel Krisman Bertazi <krisman@...labora.com>
---
 fs/f2fs/namei.c | 23 ++---------------------
 1 file changed, 2 insertions(+), 21 deletions(-)

diff --git a/fs/f2fs/namei.c b/fs/f2fs/namei.c
index 6032589099ce..558cef6e25fc 100644
--- a/fs/f2fs/namei.c
+++ b/fs/f2fs/namei.c
@@ -564,17 +564,8 @@ static struct dentry *f2fs_lookup(struct inode *dir, struct dentry *dentry,
 		goto out_iput;
 	}
 out_splice:
-#if IS_ENABLED(CONFIG_UNICODE)
-	if (!inode && IS_CASEFOLDED(dir)) {
-		/* Eventually we want to call d_add_ci(dentry, NULL)
-		 * for negative dentries in the encoding case as
-		 * well.  For now, prevent the negative dentry
-		 * from being cached.
-		 */
-		trace_f2fs_lookup_end(dir, dentry, ino, err);
-		return NULL;
-	}
-#endif
+	if (IS_ENABLED(CONFIG_UNICODE) && IS_CASEFOLDED(dir))
+		d_set_casefold_lookup(dentry);
 	new = d_splice_alias(inode, dentry);
 	err = PTR_ERR_OR_ZERO(new);
 	trace_f2fs_lookup_end(dir, dentry, ino, !new ? -ENOENT : err);
@@ -627,16 +618,6 @@ static int f2fs_unlink(struct inode *dir, struct dentry *dentry)
 	f2fs_delete_entry(de, page, dir, inode);
 	f2fs_unlock_op(sbi);
 
-#if IS_ENABLED(CONFIG_UNICODE)
-	/* VFS negative dentries are incompatible with Encoding and
-	 * Case-insensitiveness. Eventually we'll want avoid
-	 * invalidating the dentries here, alongside with returning the
-	 * negative dentries at f2fs_lookup(), when it is better
-	 * supported by the VFS for the CI case.
-	 */
-	if (IS_CASEFOLDED(dir))
-		d_invalidate(dentry);
-#endif
 	if (IS_DIRSYNC(dir))
 		f2fs_sync_fs(sbi->sb, 1);
 fail:
-- 
2.35.3