@@ -48,9 +48,13 @@ int ext3_sync_file(struct file *file, loff_t start, loff_t end, int datasync)
trace_ext3_sync_file_enter(file, datasync);
- if (inode->i_sb->s_flags & MS_RDONLY)
+ if (inode->i_sb->s_flags & MS_RDONLY) {
+ /* Make shure that we read updated state */
+ smp_rmb();
+ if (EXT3_SB(inode->i_sb)->s_mount_state & EXT3_ERROR_FS)
+ return -EROFS;
return 0;
-
+ }
ret = filemap_write_and_wait_range(inode->i_mapping, start, end);
if (ret)
goto out;
@@ -172,6 +172,11 @@ static void ext3_handle_error(struct super_block *sb)
journal_abort(journal, -EIO);
}
if (test_opt (sb, ERRORS_RO)) {
+ /*
+ * Make shure updated value of ->s_mount_state will be visiable
+ * before ->s_flags update.
+ */
+ smp_wmb();
ext3_msg(sb, KERN_CRIT,
"error: remounting filesystem read-only");
sb->s_flags |= MS_RDONLY;
@@ -291,8 +296,14 @@ void ext3_abort(struct super_block *sb, const char *function,
ext3_msg(sb, KERN_CRIT,
"error: remounting filesystem read-only");
EXT3_SB(sb)->s_mount_state |= EXT3_ERROR_FS;
- sb->s_flags |= MS_RDONLY;
set_opt(EXT3_SB(sb)->s_mount_opt, ABORT);
+ /*
+ * Make shure updated value of ->s_mount_state will be visiable
+ * before ->s_flags update.
+ */
+ smp_wmb();
+ sb->s_flags |= MS_RDONLY;
+
if (EXT3_SB(sb)->s_journal)
journal_abort(EXT3_SB(sb)->s_journal, -EIO);
}
If filesystem was aborted we will return success due to (sb->s_flags & MS_RDONLY) which is incorrect and result in data loss. In order to handle fs abort correctly we have to check fs state once we discover that it is in MS_RDONLY state Test case: http://patchwork.ozlabs.org/patch/244297/ Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org> --- fs/ext3/fsync.c | 8 ++++++-- fs/ext3/super.c | 13 ++++++++++++- 2 files changed, 18 insertions(+), 3 deletions(-)