Subject: CVE-2024-41001: io_uring/sqpoll: work around a potential audit memory leak

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

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

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

io_uring/sqpoll: work around a potential audit memory leak

kmemleak complains that there's a memory leak related to connect
handling:

unreferenced object 0xffff0001093bdf00 (size 128):
comm "iou-sqp-455", pid 457, jiffies 4294894164
hex dump (first 32 bytes):
02 00 fa ea 7f 00 00 01 00 00 00 00 00 00 00 00  ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
backtrace (crc 2e481b1a):
[<00000000c0a26af4>] kmemleak_alloc+0x30/0x38
[<000000009c30bb45>] kmalloc_trace+0x228/0x358
[<000000009da9d39f>] __audit_sockaddr+0xd0/0x138
[<0000000089a93e34>] move_addr_to_kernel+0x1a0/0x1f8
[<000000000b4e80e6>] io_connect_prep+0x1ec/0x2d4
[<00000000abfbcd99>] io_submit_sqes+0x588/0x1e48
[<00000000e7c25e07>] io_sq_thread+0x8a4/0x10e4
[<00000000d999b491>] ret_from_fork+0x10/0x20

which can can happen if:

1) The command type does something on the prep side that triggers an
   audit call.
2) The thread hasn't done any operations before this that triggered
   an audit call inside ->issue(), where we have audit_uring_entry()
   and audit_uring_exit().

Work around this by issuing a blanket NOP operation before the SQPOLL
does anything.

The Linux kernel CVE team has assigned CVE-2024-41001 to this issue.

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

	Fixed in 6.1.96 with commit 55c22375cbaa
	Fixed in 6.6.36 with commit 9e810bd99582
	Fixed in 6.9.7 with commit a40e90d93046
	Fixed in 6.10 with commit c4ce0ab27646

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-2024-41001
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:
	io_uring/sqpoll.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/55c22375cbaa24f77dd13f9ae0642915444a1227
	https://git.kernel.org/stable/c/9e810bd995823786ea30543e480e8a573e5e5667
	https://git.kernel.org/stable/c/a40e90d9304629002fb17200f7779823a81191d3
	https://git.kernel.org/stable/c/c4ce0ab27646f4206a9eb502d6fe45cb080e1cae