+ minix-fix-error-handling-in-minix_set_link.patch added to mm-nonmm-unstable branch

+ minix-fix-error-handling-in-minix_set_link.patch added to mm-nonmm-unstable branch

[Andrew Morton]

The patch titled
     Subject: minix: fix error handling in minix_set_link
has been added to the -mm mm-nonmm-unstable branch.  Its filename is
     minix-fix-error-handling-in-minix_set_link.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/minix-fix-error-handling-in-minix_set_link.patch

This patch will later appear in the mm-nonmm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: Christoph Hellwig <hch@lst.de>
Subject: minix: fix error handling in minix_set_link
Date: Wed, 18 Jan 2023 18:30:23 +0100

If minix_prepare_chunk fails, updating c/mtime and marking the dir inode
dirty is wrong, as the inode hasn't been modified.  Also propagate the
error to the caller.

Note that this moves the dir_put_page call later, but that matches other
uses of this helper in the directory code.

Link: https://lkml.kernel.org/r/20230118173027.294869-4-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Cc: Jan Kara <jack@suse.cz>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Joseph Qi <joseph.qi@linux.alibaba.com>
Cc: Mark Fasheh <mark@fasheh.com>
Cc: Matthew Wilcox <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 fs/minix/dir.c   |   22 ++++++++++++----------
 fs/minix/minix.h |    3 ++-
 fs/minix/namei.c |   10 ++++++----
 3 files changed, 20 insertions(+), 15 deletions(-)

--- a/fs/minix/dir.c~minix-fix-error-handling-in-minix_set_link
+++ a/fs/minix/dir.c
@@ -410,8 +410,8 @@ not_empty:
 }
 
 /* Releases the page */
-void minix_set_link(struct minix_dir_entry *de, struct page *page,
-	struct inode *inode)
+int minix_set_link(struct minix_dir_entry *de, struct page *page,
+		struct inode *inode)
 {
 	struct inode *dir = page->mapping->host;
 	struct minix_sb_info *sbi = minix_sb(dir->i_sb);
@@ -420,19 +420,21 @@ void minix_set_link(struct minix_dir_ent
 	int err;
 
 	lock_page(page);
-
 	err = minix_prepare_chunk(page, pos, sbi->s_dirsize);
-	if (err == 0) {
-		if (sbi->s_version == MINIX_V3)
-			((minix3_dirent *) de)->inode = inode->i_ino;
-		else
-			de->inode = inode->i_ino;
-		err = dir_commit_chunk(page, pos, sbi->s_dirsize);
-	} else {
+	if (err) {
 		unlock_page(page);
+		return err;
 	}
+	if (sbi->s_version == MINIX_V3)
+		((minix3_dirent *)de)->inode = inode->i_ino;
+	else
+		de->inode = inode->i_ino;
+	err = dir_commit_chunk(page, pos, sbi->s_dirsize);
+	if (err)
+		return err;
 	dir->i_mtime = dir->i_ctime = current_time(dir);
 	mark_inode_dirty(dir);
+	return 0;
 }
 
 struct minix_dir_entry * minix_dotdot (struct inode *dir, struct page **p)
--- a/fs/minix/minix.h~minix-fix-error-handling-in-minix_set_link
+++ a/fs/minix/minix.h
@@ -69,7 +69,8 @@ extern int minix_add_link(struct dentry*
 extern int minix_delete_entry(struct minix_dir_entry*, struct page*);
 extern int minix_make_empty(struct inode*, struct inode*);
 extern int minix_empty_dir(struct inode*);
-extern void minix_set_link(struct minix_dir_entry*, struct page*, struct inode*);
+int minix_set_link(struct minix_dir_entry *de, struct page *page,
+		struct inode *inode);
 extern struct minix_dir_entry *minix_dotdot(struct inode*, struct page**);
 extern ino_t minix_inode_by_name(struct dentry*);
 
--- a/fs/minix/namei.c~minix-fix-error-handling-in-minix_set_link
+++ a/fs/minix/namei.c
@@ -223,10 +223,11 @@ static int minix_rename(struct user_name
 		new_de = minix_find_entry(new_dentry, &new_page);
 		if (!new_de)
 			goto out_dir;
-		err = 0;
-		minix_set_link(new_de, new_page, old_inode);
+		err = minix_set_link(new_de, new_page, old_inode);
 		kunmap(new_page);
 		put_page(new_page);
+		if (err)
+			goto out_dir;
 		new_inode->i_ctime = current_time(new_inode);
 		if (dir_de)
 			drop_nlink(new_inode);
@@ -243,8 +244,9 @@ static int minix_rename(struct user_name
 	mark_inode_dirty(old_inode);
 
 	if (dir_de) {
-		minix_set_link(dir_de, dir_page, new_dir);
-		inode_dec_link_count(old_dir);
+		err = minix_set_link(dir_de, dir_page, new_dir);
+		if (!err)
+			inode_dec_link_count(old_dir);
 	}
 out_dir:
 	if (dir_de) {
_

Patches currently in -mm which might be from hch@lst.de are

fs-remove-an-outdated-comment-on-mpage_writepages.patch
ntfs3-stop-using-generic_writepages.patch
ntfs3-remove-writepage.patch
jbd2ocfs2-move-jbd2_journal_submit_inode_data_buffers-to-ocfs2.patch
ocfs2-use-filemap_fdatawrite_wbc-instead-of-generic_writepages.patch
mm-remove-generic_writepages.patch
minix-move-releasing-pages-into-unlink-and-rename.patch
minix-fix-error-handling-in-minix_delete_entry.patch
minix-fix-error-handling-in-minix_set_link.patch
minix-dont-flush-page-immediately-for-dirsync-directories.patch
sysv-dont-flush-page-immediately-for-dirsync-directories.patch
ufs-dont-flush-page-immediately-for-dirsync-directories.patch
ocfs2-dont-use-write_one_page-in-ocfs2_duplicate_clusters_by_page.patch