This is a note to let you know that I've just added the patch titled dm: fix alloc_dax error handling in alloc_dev to the 5.15-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: dm-fix-alloc_dax-error-handling-in-alloc_dev.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit e3d093f4918149685ca9303b91f9a9f61482178e Author: Christoph Hellwig <hch@xxxxxx> Date: Mon Nov 29 11:21:35 2021 +0100 dm: fix alloc_dax error handling in alloc_dev [ Upstream commit d751939235b9b7bc4af15f90a3e99288a8b844a7 ] Make sure ->dax_dev is NULL on error so that the cleanup path doesn't trip over an ERR_PTR. Reported-by: Dan Williams <dan.j.williams@xxxxxxxxx> Signed-off-by: Christoph Hellwig <hch@xxxxxx> Link: https://lore.kernel.org/r/20211129102203.2243509-2-hch@xxxxxx Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 76d9da49fda75..671bb454f1649 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -1794,8 +1794,10 @@ static struct mapped_device *alloc_dev(int minor) if (IS_ENABLED(CONFIG_DAX_DRIVER)) { md->dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops, 0); - if (IS_ERR(md->dax_dev)) + if (IS_ERR(md->dax_dev)) { + md->dax_dev = NULL; goto bad; + } } format_dev_t(md->name, MKDEV(_major, minor));