Subject: CVE-2024-47687: vdpa/mlx5: Fix invalid mr resource destroy

From: Greg Kroah-Hartman <[email-masked]>

Description
===========

In the Linux kernel, the following vulnerability has been resolved:

vdpa/mlx5: Fix invalid mr resource destroy

Certain error paths from mlx5_vdpa_dev_add() can end up releasing mr
resources which never got initialized in the first place.

This patch adds the missing check in mlx5_vdpa_destroy_mr_resources()
to block releasing non-initialized mr resources.

Reference trace:

  mlx5_core 0000:08:00.2: mlx5_vdpa_dev_add:3274:(pid 2700) warning: No mac address provisioned?
  BUG: kernel NULL pointer dereference, address: 0000000000000000
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  PGD 140216067 P4D 0
  Oops: 0000 [#1] PREEMPT SMP NOPTI
  CPU: 8 PID: 2700 Comm: vdpa Kdump: loaded Not tainted 5.14.0-496.el9.x86_64 #1
  Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
  RIP: 0010:vhost_iotlb_del_range+0xf/0xe0 [vhost_iotlb]
  Code: [...]
  RSP: 0018:ff1c823ac23077f0 EFLAGS: 00010246
  RAX: ffffffffc1a21a60 RBX: ffffffff899567a0 RCX: 0000000000000000
  RDX: ffffffffffffffff RSI: 0000000000000000 RDI: 0000000000000000
  RBP: ff1bda1f7c21e800 R08: 0000000000000000 R09: ff1c823ac2307670
  R10: ff1c823ac2307668 R11: ffffffff8a9e7b68 R12: 0000000000000000
  R13: 0000000000000000 R14: ff1bda1f43e341a0 R15: 00000000ffffffea
  FS:  00007f56eba7c740(0000) GS:ff1bda269f800000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000000 CR3: 0000000104d90001 CR4: 0000000000771ef0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:

   ? show_trace_log_lvl+0x1c4/0x2df
   ? show_trace_log_lvl+0x1c4/0x2df
   ? mlx5_vdpa_free+0x3d/0x150 [mlx5_vdpa]
   ? __die_body.cold+0x8/0xd
   ? page_fault_oops+0x134/0x170
   ? __irq_work_queue_local+0x2b/0xc0
   ? irq_work_queue+0x2c/0x50
   ? exc_page_fault+0x62/0x150
   ? asm_exc_page_fault+0x22/0x30
   ? __pfx_mlx5_vdpa_free+0x10/0x10 [mlx5_vdpa]
   ? vhost_iotlb_del_range+0xf/0xe0 [vhost_iotlb]
   mlx5_vdpa_free+0x3d/0x150 [mlx5_vdpa]
   vdpa_release_dev+0x1e/0x50 [vdpa]
   device_release+0x31/0x90
   kobject_cleanup+0x37/0x130
   mlx5_vdpa_dev_add+0x2d2/0x7a0 [mlx5_vdpa]
   vdpa_nl_cmd_dev_add_set_doit+0x277/0x4c0 [vdpa]
   genl_family_rcv_msg_doit+0xd9/0x130
   genl_family_rcv_msg+0x14d/0x220
   ? __pfx_vdpa_nl_cmd_dev_add_set_doit+0x10/0x10 [vdpa]
   ? _copy_to_user+0x1a/0x30
   ? move_addr_to_user+0x4b/0xe0
   genl_rcv_msg+0x47/0xa0
   ? __import_iovec+0x46/0x150
   ? __pfx_genl_rcv_msg+0x10/0x10
   netlink_rcv_skb+0x54/0x100
   genl_rcv+0x24/0x40
   netlink_unicast+0x245/0x370
   netlink_sendmsg+0x206/0x440
   __sys_sendto+0x1dc/0x1f0
   ? do_read_fault+0x10c/0x1d0
   ? do_pte_missing+0x10d/0x190
   __x64_sys_sendto+0x20/0x30
   do_syscall_64+0x5c/0xf0
   ? __count_memcg_events+0x4f/0xb0
   ? mm_account_fault+0x6c/0x100
   ? handle_mm_fault+0x116/0x270
   ? do_user_addr_fault+0x1d6/0x6a0
   ? do_syscall_64+0x6b/0xf0
   ? clear_bhb_loop+0x25/0x80
   ? clear_bhb_loop+0x25/0x80
   ? clear_bhb_loop+0x25/0x80
   ? clear_bhb_loop+0x25/0x80
   ? clear_bhb_loop+0x25/0x80
   entry_SYSCALL_64_after_hwframe+0x78/0x80

The Linux kernel CVE team has assigned CVE-2024-47687 to this issue.

Affected and fixed versions
===========================

	Issue introduced in 6.7 with commit 512c0cdd80c1 and fixed in 6.10.13 with commit b6fbb1c7801f
	Issue introduced in 6.7 with commit 512c0cdd80c1 and fixed in 6.11.2 with commit 5fe351def237
	Issue introduced in 6.7 with commit 512c0cdd80c1 and fixed in 6.12-rc1 with commit dc12502905b7

Please see https://www.kernel.org for a full list of currently supported
kernel versions by the kernel community.

Unaffected versions might change over time as fixes are backported to
older supported kernel versions.  The official CVE entry at
	https://cve.org/CVERecord/?id=CVE-2024-47687
will be updated if fixes are backported, please check that for the most
up to date information about this issue.

Affected files
==============

The file(s) affected by this issue are:
	drivers/vdpa/mlx5/core/mr.c

Mitigation
==========

The Linux kernel CVE team recommends that you update to the latest
stable kernel version for this, and many other bugfixes.  Individual
changes are never tested alone, but rather are part of a larger kernel
release.  Cherry-picking individual commits is not recommended or
supported by the Linux kernel community at all.  If however, updating to
the latest release is impossible, the individual changes to resolve this
issue can be found at these commits:
	https://git.kernel.org/stable/c/b6fbb1c7801f46a0e5461c02904eab0d7535c790
	https://git.kernel.org/stable/c/5fe351def237df1ad29aa8af574350bc5340b4cf
	https://git.kernel.org/stable/c/dc12502905b7a3de9097ea6b98870470c2921e09