Commit 7a636b4f authored Aug 13, 2024 by Khazhismel Kumykov Committed by Mikulas Patocka Aug 13, 2024

dm resume: don't return EINVAL when signalled



If the dm_resume method is called on a device that is not suspended, the
method will suspend the device briefly, before resuming it (so that the
table will be swapped).

However, there was a bug that the return value of dm_suspended_md was not
checked. dm_suspended_md may return an error when it is interrupted by a
signal. In this case, do_resume would call dm_swap_table, which would
return -EINVAL.

This commit fixes the logic, so that error returned by dm_suspend is
checked and the resume operation is undone.

Signed-off-by: Mikulas Patocka <mpatocka@redhat.com>
Signed-off-by: Khazhismel Kumykov <khazhy@google.com>
Cc: stable@vger.kernel.org

parent 1e1fd567

drivers/md/dm-ioctl.c

+20 −2

Original line number	Diff line number	Diff line
		@@ -1181,8 +1181,26 @@ static int do_resume(struct dm_ioctl *param)
		suspend_flags &= ~DM_SUSPEND_LOCKFS_FLAG;
		if (param->flags & DM_NOFLUSH_FLAG)
		suspend_flags \|= DM_SUSPEND_NOFLUSH_FLAG;
		if (!dm_suspended_md(md))
		dm_suspend(md, suspend_flags);
		if (!dm_suspended_md(md)) {
		r = dm_suspend(md, suspend_flags);
		if (r) {
		down_write(&_hash_lock);
		hc = dm_get_mdptr(md);
		if (hc && !hc->new_map) {
		hc->new_map = new_map;
		new_map = NULL;
		} else {
		r = -ENXIO;
		}
		up_write(&_hash_lock);
		if (new_map) {
		dm_sync_table(md);
		dm_table_destroy(new_map);
		}
		dm_put(md);
		return r;
		}
		}

		old_size = dm_get_size(md);
		old_map = dm_swap_table(md, new_map);