1f2b324e82
commit 32b2397c1e56f33b0b1881def965bb89bd12f448 upstream. There is a use after free crash when the pmem driver tears down its mapping while I/O is still inbound. This is triggered by driver unbind, "ndctl destroy-namespace", while I/O is in flight. Fix the sequence of blk_cleanup_queue() vs memunmap(). The crash signature is of the form: BUG: unable to handle page fault for address: ffffc90080200000 CPU: 36 PID: 9606 Comm: systemd-udevd Call Trace: ? pmem_do_bvec+0xf9/0x3a0 ? xas_alloc+0x55/0xd0 pmem_rw_page+0x4b/0x80 bdev_read_page+0x86/0xb0 do_mpage_readpage+0x5d4/0x7a0 ? lru_cache_add+0xe/0x10 mpage_readpages+0xf9/0x1c0 ? bd_link_disk_holder+0x1a0/0x1a0 blkdev_readpages+0x1d/0x20 read_pages+0x67/0x1a0 ndctl Call Trace in vmcore: PID: 23473 TASK: ffff88c4fbbe8000 CPU: 1 COMMAND: "ndctl" __schedule schedule blk_mq_freeze_queue_wait blk_freeze_queue blk_cleanup_queue pmem_release_queue devm_action_release release_nodes devres_release_all device_release_driver_internal device_driver_detach unbind_store Cc: <stable@vger.kernel.org> Signed-off-by: sumiyawang <sumiyawang@tencent.com> Reviewed-by: yongduan <yongduan@tencent.com> Link: https://lore.kernel.org/r/1629632949-14749-1-git-send-email-sumiyawang@tencent.com Fixes: 50f44ee7248a ("mm/devm_memremap_pages: fix final page put race") Signed-off-by: Dan Williams <dan.j.williams@intel.com> [tyhicks: Minor contextual change in pmem_attach_disk() due to the transition to 'struct range' not yet taking place. Preserve the memcpy() call rather than initializing the range struct. That change was introduced in v5.10 with commit a4574f63edc6 ("mm/memremap_pages: convert to 'struct range'")] Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.