Subject: CVE-2021-47265: RDMA: Verify port when creating flow rule

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

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

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

RDMA: Verify port when creating flow rule

Validate port value provided by the user and with that remove no longer
needed validation by the driver.  The missing check in the mlx5_ib driver
could cause to the below oops.

Call trace:
  _create_flow_rule+0x2d4/0xf28 [mlx5_ib]
  mlx5_ib_create_flow+0x2d0/0x5b0 [mlx5_ib]
  ib_uverbs_ex_create_flow+0x4cc/0x624 [ib_uverbs]
  ib_uverbs_handler_UVERBS_METHOD_INVOKE_WRITE+0xd4/0x150 [ib_uverbs]
  ib_uverbs_cmd_verbs.isra.7+0xb28/0xc50 [ib_uverbs]
  ib_uverbs_ioctl+0x158/0x1d0 [ib_uverbs]
  do_vfs_ioctl+0xd0/0xaf0
  ksys_ioctl+0x84/0xb4
  __arm64_sys_ioctl+0x28/0xc4
  el0_svc_common.constprop.3+0xa4/0x254
  el0_svc_handler+0x84/0xa0
  el0_svc+0x10/0x26c
 Code: b9401260 f9615681 51000400 8b001c20 (f9403c1a)

The Linux kernel CVE team has assigned CVE-2021-47265 to this issue.

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

	Issue introduced in 3.12 with commit 436f2ad05a0b and fixed in 5.12.11 with commit 8dc1b0e0ca20
	Issue introduced in 3.12 with commit 436f2ad05a0b and fixed in 5.13 with commit 2adcb4c5a52a

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-2021-47265
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/infiniband/core/uverbs_cmd.c
	drivers/infiniband/hw/mlx4/main.c
	drivers/infiniband/hw/mlx5/fs.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/8dc1b0e0ca204596c50bcd159ee069ae0f998176
	https://git.kernel.org/stable/c/2adcb4c5a52a2623cd2b43efa7041e74d19f3a5e