From: Darrick J. Wong <djwong@kernel.org>
Date: Wed, 21 May 2025 22:36:28 +0000 (-0700)
Subject: fuse2fs: support XATTR_CREATE/REPLACE in setxattr
X-Git-Tag: v1.47.3-rc1~58
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5c7fec6121e6b24732db30ac408d9c8ab4805245;p=thirdparty%2Fe2fsprogs.git

fuse2fs: support XATTR_CREATE/REPLACE in setxattr

Fix the setxattr implementation to support the create and replace flags
instead of performing an upsert regardless of inputs.

Cc: linux-ext4@vger.kernel.org # v1.43
Fixes: 81cbf1ef4f5dab ("misc: add fuse2fs, a FUSE server for e2fsprogs")
Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Link: https://lore.kernel.org/r/174786677657.1383760.12232239908991346763.stgit@frogsfrogsfrogs
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
---

diff --git a/misc/fuse2fs.c b/misc/fuse2fs.c
index 41489281..e33a0a88 100644
--- a/misc/fuse2fs.c
+++ b/misc/fuse2fs.c
@@ -18,6 +18,9 @@
 # include <linux/falloc.h>
 # include <linux/xattr.h>
 #endif
+#ifdef HAVE_SYS_XATTR_H
+#include <sys/xattr.h>
+#endif
 #include <sys/ioctl.h>
 #include <unistd.h>
 #include <ctype.h>
@@ -2517,7 +2520,7 @@ out:
 
 static int op_setxattr(const char *path EXT2FS_ATTR((unused)),
 		       const char *key, const char *value,
-		       size_t len, int flags EXT2FS_ATTR((unused)))
+		       size_t len, int flags)
 {
 	struct fuse_context *ctxt = fuse_get_context();
 	struct fuse2fs *ff = (struct fuse2fs *)ctxt->private_data;
@@ -2527,6 +2530,9 @@ static int op_setxattr(const char *path EXT2FS_ATTR((unused)),
 	errcode_t err;
 	int ret = 0;
 
+	if (flags & ~(XATTR_CREATE | XATTR_REPLACE))
+		return -EOPNOTSUPP;
+
 	FUSE2FS_CHECK_CONTEXT(ff);
 	fs = ff->fs;
 	pthread_mutex_lock(&ff->bfl);
@@ -2561,6 +2567,31 @@ static int op_setxattr(const char *path EXT2FS_ATTR((unused)),
 		goto out2;
 	}
 
+	if (flags & (XATTR_CREATE | XATTR_REPLACE)) {
+		void *buf;
+		size_t buflen;
+
+		err = ext2fs_xattr_get(h, key, &buf, &buflen);
+		switch (err) {
+		case EXT2_ET_EA_KEY_NOT_FOUND:
+			if (flags & XATTR_REPLACE) {
+				ret = -ENODATA;
+				goto out2;
+			}
+			break;
+		case 0:
+			ext2fs_free_mem(&buf);
+			if (flags & XATTR_CREATE) {
+				ret = -EEXIST;
+				goto out2;
+			}
+			break;
+		default:
+			ret = translate_error(fs, ino, err);
+			goto out2;
+		}
+	}
+
 	err = ext2fs_xattr_set(h, key, value, len);
 	if (err) {
 		ret = translate_error(fs, ino, err);