Re: [syzbot] Re: KMSAN: uninit-value in hfsplus_rename_cat()

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Subject: Re: KMSAN: uninit-value in hfsplus_rename_cat()
Author: dmantipov@yandex.ru

#syz test https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 231825b2e1ff6ba799c5eaf396d3ab2354e37c6b

diff --git a/fs/hfsplus/super.c b/fs/hfsplus/super.c
index 948b8aaee33e..9352efbbf736 100644
--- a/fs/hfsplus/super.c
+++ b/fs/hfsplus/super.c
@@ -360,6 +360,12 @@ static int hfsplus_reconfigure(struct fs_context *fc)
 			pr_warn("filesystem is marked journaled, leaving read-only.\n");
 			sb->s_flags |= SB_RDONLY;
 			fc->sb_flags |= SB_RDONLY;
+		} else {
+			pr_err("remount from read-ony to read-write "
+			       "is not supported, leaving read-only.\n");
+			sb->s_flags |= SB_RDONLY;
+			fc->sb_flags |= SB_RDONLY;
+			return -ENOSYS;
 		}
 	}
 	return 0;