linux-ext4 - [PATCH 25/29] fuse2fs: fix removing ea inodes when freeing a file

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Message-ID: <174786677996.1383760.7408606469648643965.stgit@frogsfrogsfrogs>
Date: Wed, 21 May 2025 15:41:26 -0700
From: "Darrick J. Wong" <djwong@...nel.org>
To: tytso@....edu
Cc: linux-ext4@...r.kernel.org
Subject: [PATCH 25/29] fuse2fs: fix removing ea inodes when freeing a file

From: Darrick J. Wong <djwong@...nel.org>

If the filesystem has ea_inode set, then each file that has xattrs might
have stored an xattr value in a separate inode.  These inodes also need
to be freed, so create a library function to do that, and call it from
the fuse2fs unlink method.  Seen by ext4/026.

Signed-off-by: "Darrick J. Wong" <djwong@...nel.org>
---
 lib/ext2fs/ext2fs.h          |    1 +
 debian/libext2fs2t64.symbols |    1 +
 lib/ext2fs/ext_attr.c        |   19 +++++++++++++++++++
 misc/fuse2fs.c               |   40 ++++++++++++++++++++++++++++++++++++++++
 4 files changed, 61 insertions(+)


diff --git a/lib/ext2fs/ext2fs.h b/lib/ext2fs/ext2fs.h
index 1527719554f001..2661e10f57c047 100644
--- a/lib/ext2fs/ext2fs.h
+++ b/lib/ext2fs/ext2fs.h
@@ -1406,6 +1406,7 @@ errcode_t ext2fs_xattr_set(struct ext2_xattr_handle *handle,
 			   size_t value_len);
 errcode_t ext2fs_xattr_remove(struct ext2_xattr_handle *handle,
 			      const char *key);
+errcode_t ext2fs_xattr_remove_all(struct ext2_xattr_handle *handle);
 errcode_t ext2fs_xattrs_open(ext2_filsys fs, ext2_ino_t ino,
 			     struct ext2_xattr_handle **handle);
 errcode_t ext2fs_xattrs_close(struct ext2_xattr_handle **handle);
diff --git a/debian/libext2fs2t64.symbols b/debian/libext2fs2t64.symbols
index 35af8880dd4843..fc1e16ff1e086c 100644
--- a/debian/libext2fs2t64.symbols
+++ b/debian/libext2fs2t64.symbols
@@ -670,6 +670,7 @@ libext2fs.so.2 libext2fs2t64 #MINVER#
  ext2fs_xattr_get@...e 1.43
  ext2fs_xattr_inode_max_size@...e 1.43
  ext2fs_xattr_remove@...e 1.43
+ ext2fs_xattr_remove_all@...e 1.47.3
  ext2fs_xattr_set@...e 1.43
  ext2fs_xattrs_close@...e 1.43
  ext2fs_xattrs_count@...e 1.43
diff --git a/lib/ext2fs/ext_attr.c b/lib/ext2fs/ext_attr.c
index 1b5f90d33f3cd4..7723d0f918d6a8 100644
--- a/lib/ext2fs/ext_attr.c
+++ b/lib/ext2fs/ext_attr.c
@@ -1355,6 +1355,7 @@ static errcode_t xattr_inode_dec_ref(ext2_filsys fs, ext2_ino_t ino)
 			goto out;
 	}
 
+	inode.i_flags &= ~EXT4_EA_INODE_FL;
 	ext2fs_inode_alloc_stats2(fs, ino, -1 /* inuse */, 0 /* is_dir */);
 
 write_out:
@@ -1725,6 +1726,24 @@ errcode_t ext2fs_xattr_remove(struct ext2_xattr_handle *handle,
 	return 0;
 }
 
+errcode_t ext2fs_xattr_remove_all(struct ext2_xattr_handle *handle)
+{
+	struct ext2_xattr *x;
+	struct ext2_xattr *end = handle->attrs + handle->count;
+
+	EXT2_CHECK_MAGIC(handle, EXT2_ET_MAGIC_EA_HANDLE);
+	for (x = handle->attrs; x < end; x++) {
+		ext2fs_free_mem(&x->name);
+		ext2fs_free_mem(&x->value);
+		if (x->ea_ino)
+			xattr_inode_dec_ref(handle->fs, x->ea_ino);
+	}
+
+	handle->ibody_count = 0;
+	handle->count = 0;
+	return ext2fs_xattrs_write(handle);
+}
+
 errcode_t ext2fs_xattrs_open(ext2_filsys fs, ext2_ino_t ino,
 			     struct ext2_xattr_handle **handle)
 {
diff --git a/misc/fuse2fs.c b/misc/fuse2fs.c
index a630d93f5f48a8..46ae73bd4e25bb 100644
--- a/misc/fuse2fs.c
+++ b/misc/fuse2fs.c
@@ -1178,6 +1178,40 @@ static int unlink_file_by_name(struct fuse2fs *ff, const char *path)
 	return update_mtime(fs, dir, NULL);
 }
 
+static errcode_t remove_ea_inodes(struct fuse2fs *ff, ext2_ino_t ino,
+				  struct ext2_inode_large *inode)
+{
+	ext2_filsys fs = ff->fs;
+	struct ext2_xattr_handle *h;
+	errcode_t err;
+
+	/*
+	 * The xattr handle maintains its own private copy of the inode, so
+	 * write ours to disk so that we can read it.
+	 */
+	err = fuse2fs_write_inode(fs, ino, inode);
+	if (err)
+		return err;
+
+	err = ext2fs_xattrs_open(fs, ino, &h);
+	if (err)
+		return err;
+
+	err = ext2fs_xattrs_read(h);
+	if (err)
+		goto out_close;
+
+	err = ext2fs_xattr_remove_all(h);
+	if (err)
+		goto out_close;
+
+out_close:
+	ext2fs_xattrs_close(&h);
+
+	/* Now read the inode back in. */
+	return fuse2fs_read_inode(fs, ino, inode);
+}
+
 static int remove_inode(struct fuse2fs *ff, ext2_ino_t ino)
 {
 	ext2_filsys fs = ff->fs;
@@ -1213,6 +1247,12 @@ static int remove_inode(struct fuse2fs *ff, ext2_ino_t ino)
 	if (inode.i_links_count)
 		goto write_out;
 
+	if (ext2fs_has_feature_ea_inode(fs->super)) {
+		err = remove_ea_inodes(ff, ino, &inode);
+		if (err)
+			goto write_out;
+	}
+
 	/* Nobody holds this file; free its blocks! */
 	err = ext2fs_free_ext_attr(fs, ino, &inode);
 	if (err)