Subject: CVE-2024-38539: RDMA/cma: Fix kmemleak in rdma_core observed during blktests nvme/rdma use siw

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

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

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

RDMA/cma: Fix kmemleak in rdma_core observed during blktests nvme/rdma use siw

When running blktests nvme/rdma, the following kmemleak issue will appear.

kmemleak: Kernel memory leak detector initialized (mempool available:36041)
kmemleak: Automatic memory scanning thread started
kmemleak: 2 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
kmemleak: 8 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
kmemleak: 17 new suspected memory leaks (see /sys/kernel/debug/kmemleak)
kmemleak: 4 new suspected memory leaks (see /sys/kernel/debug/kmemleak)

unreferenced object 0xffff88855da53400 (size 192):
  comm "rdma", pid 10630, jiffies 4296575922
  hex dump (first 32 bytes):
    37 00 00 00 00 00 00 00 c0 ff ff ff 1f 00 00 00  7...............
    10 34 a5 5d 85 88 ff ff 10 34 a5 5d 85 88 ff ff  .4.].....4.]....
  backtrace (crc 47f66721):
    [<ffffffff911251bd>] kmalloc_trace+0x30d/0x3b0
    [<ffffffffc2640ff7>] alloc_gid_entry+0x47/0x380 [ib_core]
    [<ffffffffc2642206>] add_modify_gid+0x166/0x930 [ib_core]
    [<ffffffffc2643468>] ib_cache_update.part.0+0x6d8/0x910 [ib_core]
    [<ffffffffc2644e1a>] ib_cache_setup_one+0x24a/0x350 [ib_core]
    [<ffffffffc263949e>] ib_register_device+0x9e/0x3a0 [ib_core]
    [<ffffffffc2a3d389>] 0xffffffffc2a3d389
    [<ffffffffc2688cd8>] nldev_newlink+0x2b8/0x520 [ib_core]
    [<ffffffffc2645fe3>] rdma_nl_rcv_msg+0x2c3/0x520 [ib_core]
    [<ffffffffc264648c>]
rdma_nl_rcv_skb.constprop.0.isra.0+0x23c/0x3a0 [ib_core]
    [<ffffffff9270e7b5>] netlink_unicast+0x445/0x710
    [<ffffffff9270f1f1>] netlink_sendmsg+0x761/0xc40
    [<ffffffff9249db29>] __sys_sendto+0x3a9/0x420
    [<ffffffff9249dc8c>] __x64_sys_sendto+0xdc/0x1b0
    [<ffffffff92db0ad3>] do_syscall_64+0x93/0x180
    [<ffffffff92e00126>] entry_SYSCALL_64_after_hwframe+0x71/0x79

The root cause: rdma_put_gid_attr is not called when sgid_attr is set
to ERR_PTR(-ENODEV).

The Linux kernel CVE team has assigned CVE-2024-38539 to this issue.

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

	Issue introduced in 6.6 with commit f8ef1be816bf and fixed in 6.6.33 with commit 3eb127dc408b
	Issue introduced in 6.6 with commit f8ef1be816bf and fixed in 6.8.12 with commit 6564fc181840
	Issue introduced in 6.6 with commit f8ef1be816bf and fixed in 6.9.3 with commit b3a7fb93afd8
	Issue introduced in 6.6 with commit f8ef1be816bf and fixed in 6.10 with commit 9c0731832d3b

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-2024-38539
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/cma.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/3eb127dc408bf7959a4920d04d16ce10e863686a
	https://git.kernel.org/stable/c/6564fc1818404254d1c9f7d75b403b4941516d26
	https://git.kernel.org/stable/c/b3a7fb93afd888793ef226e9665fbda98a95c48e
	https://git.kernel.org/stable/c/9c0731832d3b7420cbadba6a7f334363bc8dfb15