This is a note to let you know that I've just added the patch titled fs: avoid empty option when generating legacy mount string to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: fs-avoid-empty-option-when-generating-legacy-mount-string.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From 62176420274db5b5127cd7a0083a9aeb461756ee Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Thomas=20Wei=C3=9Fschuh?= <linux@xxxxxxxxxxxxxx> Date: Wed, 7 Jun 2023 19:28:48 +0200 Subject: fs: avoid empty option when generating legacy mount string MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Thomas Weißschuh <linux@xxxxxxxxxxxxxx> commit 62176420274db5b5127cd7a0083a9aeb461756ee upstream. As each option string fragment is always prepended with a comma it would happen that the whole string always starts with a comma. This could be interpreted by filesystem drivers as an empty option and may produce errors. For example the NTFS driver from ntfs.ko behaves like this and fails when mounted via the new API. Link: https://github.com/util-linux/util-linux/issues/2298 Signed-off-by: Thomas Weißschuh <linux@xxxxxxxxxxxxxx> Fixes: 3e1aeb00e6d1 ("vfs: Implement a filesystem superblock creation/configuration context") Cc: stable@xxxxxxxxxxxxxxx Message-Id: <20230607-fs-empty-option-v1-1-20c8dbf4671b@xxxxxxxxxxxxxx> Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/fs_context.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/fs/fs_context.c +++ b/fs/fs_context.c @@ -543,7 +543,8 @@ static int legacy_parse_param(struct fs_ return -ENOMEM; } - ctx->legacy_data[size++] = ','; + if (size) + ctx->legacy_data[size++] = ','; len = strlen(param->key); memcpy(ctx->legacy_data + size, param->key, len); size += len; Patches currently in stable-queue which might be from linux@xxxxxxxxxxxxxx are queue-5.10/fs-avoid-empty-option-when-generating-legacy-mount-string.patch