diff options
| author | Lukas Czerner <lczerner@redhat.com> | 2020-07-23 17:05:26 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-09-03 11:26:56 +0200 |
| commit | e579635669da76333e8b4dcd8cf5c4dabbb9410e (patch) | |
| tree | 9c1a6ef43d3479ae48792c7d5c4961c7214e3abc /fs/ext4 | |
| parent | 3a53d012bd26b11a5f869466dd288e57cb12ede6 (diff) | |
ext4: handle option set by mount flags correctly
[ Upstream commit f25391ebb475d3ffb3aa61bb90e3594c841749ef ]
Currently there is a problem with mount options that can be both set by
vfs using mount flags or by a string parsing in ext4.
i_version/iversion options gets lost after remount, for example
$ mount -o i_version /dev/pmem0 /mnt
$ grep pmem0 /proc/self/mountinfo | grep i_version
310 95 259:0 / /mnt rw,relatime shared:163 - ext4 /dev/pmem0 rw,seclabel,i_version
$ mount -o remount,ro /mnt
$ grep pmem0 /proc/self/mountinfo | grep i_version
nolazytime gets ignored by ext4 on remount, for example
$ mount -o lazytime /dev/pmem0 /mnt
$ grep pmem0 /proc/self/mountinfo | grep lazytime
310 95 259:0 / /mnt rw,relatime shared:163 - ext4 /dev/pmem0 rw,lazytime,seclabel
$ mount -o remount,nolazytime /mnt
$ grep pmem0 /proc/self/mountinfo | grep lazytime
310 95 259:0 / /mnt rw,relatime shared:163 - ext4 /dev/pmem0 rw,lazytime,seclabel
Fix it by applying the SB_LAZYTIME and SB_I_VERSION flags from *flags to
s_flags before we parse the option and use the resulting state of the
same flags in *flags at the end of successful remount.
Signed-off-by: Lukas Czerner <lczerner@redhat.com>
Reviewed-by: Ritesh Harjani <riteshh@linux.ibm.com>
Link: https://lore.kernel.org/r/20200723150526.19931-1-lczerner@redhat.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'fs/ext4')
| -rw-r--r-- | fs/ext4/super.c | 21 |
1 files changed, 16 insertions, 5 deletions
diff --git a/fs/ext4/super.c b/fs/ext4/super.c index 76c552939439..92a6741c4bdd 100644 --- a/fs/ext4/super.c +++ b/fs/ext4/super.c @@ -5342,7 +5342,7 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) { struct ext4_super_block *es; struct ext4_sb_info *sbi = EXT4_SB(sb); - unsigned long old_sb_flags; + unsigned long old_sb_flags, vfs_flags; struct ext4_mount_options old_opts; int enable_quota = 0; ext4_group_t g; @@ -5385,6 +5385,14 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) if (sbi->s_journal && sbi->s_journal->j_task->io_context) journal_ioprio = sbi->s_journal->j_task->io_context->ioprio; + /* + * Some options can be enabled by ext4 and/or by VFS mount flag + * either way we need to make sure it matches in both *flags and + * s_flags. Copy those selected flags from *flags to s_flags + */ + vfs_flags = SB_LAZYTIME | SB_I_VERSION; + sb->s_flags = (sb->s_flags & ~vfs_flags) | (*flags & vfs_flags); + if (!parse_options(data, sb, NULL, &journal_ioprio, 1)) { err = -EINVAL; goto restore_opts; @@ -5438,9 +5446,6 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) set_task_ioprio(sbi->s_journal->j_task, journal_ioprio); } - if (*flags & SB_LAZYTIME) - sb->s_flags |= SB_LAZYTIME; - if ((bool)(*flags & SB_RDONLY) != sb_rdonly(sb)) { if (sbi->s_mount_flags & EXT4_MF_FS_ABORTED) { err = -EROFS; @@ -5580,7 +5585,13 @@ static int ext4_remount(struct super_block *sb, int *flags, char *data) } #endif - *flags = (*flags & ~SB_LAZYTIME) | (sb->s_flags & SB_LAZYTIME); + /* + * Some options can be enabled by ext4 and/or by VFS mount flag + * either way we need to make sure it matches in both *flags and + * s_flags. Copy those selected flags from s_flags to *flags + */ + *flags = (*flags & ~vfs_flags) | (sb->s_flags & vfs_flags); + ext4_msg(sb, KERN_INFO, "re-mounted. Opts: %s", orig_data); kfree(orig_data); return 0; |