CVE-2026-98358: IB/iser: reject a remote invalidation of an unregistered direction

CVE-2026-98358: IB/iser: reject a remote invalidation of an unregistered direction

[Greg Kroah-Hartman]

From: Greg Kroah-Hartman <gregkh@kernel.org>

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

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

IB/iser: reject a remote invalidation of an unregistered direction

A write command whose data is sent entirely as immediate data is not
registered.  iser_reg_mem_fastreg() takes the DMA key path and leaves
rdma_reg[ISER_DIR_OUT].desc at NULL, while iser_dma_map_task_data() has
already set dir[ISER_DIR_OUT].

iser_check_remote_inv() looks at dir[] alone and hands the descriptor to
iser_inv_desc(), which reads desc->sig_protected.  A target that answers
such a command with IB_WR_SEND_WITH_INV faults the initiator.
Leaving those commands unregistered is deliberate.

The same function already terminates the connection when a target sends
a remote invalidation the initiator did not ask for.  A target that
invalidates a direction that was never registered is in the same class,
so give it the same answer.

  Oops: general protection fault, probably for non-canonical address 0xdffffc0000000004: 0000 [#1] SMP KASAN NOPTI
  KASAN: null-ptr-deref in range [0x0000000000000020-0x0000000000000027]
  CPU: 0 UID: 0 PID: 40 Comm: kworker/u8:2 Not tainted 7.2.0-rc5-ISERHOST-gf5098b6bae76-dirty #3 PREEMPT(lazy)
  Hardware name: QEMU Ubuntu 24.04 PC v2 (i440FX + PIIX, arch_caps fix, 1996), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
  Workqueue: rxe_wq do_work
  RIP: 0010:iser_task_rsp+0x6d6/0xec0
  Code: 48 c1 ea 03 80 3c 02 00 0f 85 ba 06 00 00 48 8b 9b 78 01 00 00 48 b8 00 00 00 00 00 fc ff df 48 8d 7b 20 48 89 fa 48 c1 ea 03 <0f> b6 04 02 84 c0 74 06 0f 8e 76 06 00 00 80 7b 20 00 0f 84 3d 04
  RSP: 0018:ffff88811b008db8 EFLAGS: 00010202
  RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000001848
  RDX: 0000000000000004 RSI: 1ffff11021587b12 RDI: 0000000000000020
  RBP: ffff88810adc1ae4 R08: ffff888109b7f860 R09: ffffffff90a922c0
  R10: ffff88810adc1a1c R11: 000000000000003c R12: ffff888109b7f800
  R13: ffff88810adc1acc R14: ffff888109b7f820 R15: 0000000000000000
  FS:  0000000000000000(0000) GS:ffff88818a676000(0000) knlGS:0000000000000000
  CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 00000000005afe2b CR3: 000000010af23005 CR4: 0000000000770ef0
  PKRU: 55555554
  Call Trace:
   <IRQ>
   __ib_process_cq+0xe1/0x390
   ib_poll_handler+0x6e/0x200
   irq_poll_softirq+0x1df/0x480
   ? clockevents_program_event+0x2ba/0x860
   ? __pfx_irq_poll_softirq+0x10/0x10
   handle_softirqs+0x18e/0x590
   ? __pfx_handle_softirqs+0x10/0x10
   ? __hrtimer_rearm_deferred+0x156/0x450
   do_softirq+0x3b/0x60
   </IRQ>
   <TASK>
   __local_bh_enable_ip+0x61/0x70
   __alloc_skb+0x732/0x890
   ? _raw_spin_lock_irqsave+0x85/0xe0
   ? __pfx___alloc_skb+0x10/0x10
   ? _raw_read_unlock_irqrestore+0x16/0x50
   rxe_init_packet+0x16b/0x4f0
   prepare_ack_packet+0xb8/0x830
   rxe_receiver+0x499/0x9980
   ? __pfx_rxe_receiver+0x10/0x10
   ? rxe_completer+0x29e5/0x38c0
   ? hrtimer_start_range_ns_common+0x75f/0x1730
   ? hrtimer_start_range_ns+0xa6/0x2c0
   ? __pfx__raw_spin_lock_irqsave+0x10/0x10
   ? __pfx_rxe_receiver+0x10/0x10
   do_work+0x144/0x470
   process_one_work+0x633/0x1030
   ? assign_work+0x11d/0x370
   worker_thread+0x45b/0xd10
   ? __pfx_worker_thread+0x10/0x10
   kthread+0x2c6/0x3b0
   ? recalc_sigpending+0x15c/0x1e0
   ? __pfx_kthread+0x10/0x10
   ret_from_fork+0x36e/0x5a0
   ? __pfx_ret_from_fork+0x10/0x10
   ? __switch_to+0x572/0xdd0
   ? __pfx_kthread+0x10/0x10
   ret_from_fork_asm+0x1a/0x30
   </TASK>
  Modules linked in:
  ---[ end trace 0000000000000000 ]---

The Linux kernel CVE team has assigned CVE-2026-98358 to this issue.


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

	Issue introduced in 4.5 with commit 59caaed7a72a0e3750dfb84636dae6b781559310 and fixed in 5.10.271 with commit 198e4db9add54a50cce60a5d80b8f0ee5456b65a
	Issue introduced in 4.5 with commit 59caaed7a72a0e3750dfb84636dae6b781559310 and fixed in 5.15.222 with commit b9e37452915feaa8422af87dea5d0c16a7d1ff13
	Issue introduced in 4.5 with commit 59caaed7a72a0e3750dfb84636dae6b781559310 and fixed in 6.1.189 with commit 19ddd4af7fce9200e70882f622011e9dd130f427
	Issue introduced in 4.5 with commit 59caaed7a72a0e3750dfb84636dae6b781559310 and fixed in 6.6.158 with commit 9d145a2d8d6f8f2cc460b80df41870819048f2a0
	Issue introduced in 4.5 with commit 59caaed7a72a0e3750dfb84636dae6b781559310 and fixed in 6.12.112 with commit b4d278c91209931199db9c0836dc2e21a7593dad
	Issue introduced in 4.5 with commit 59caaed7a72a0e3750dfb84636dae6b781559310 and fixed in 6.18.54 with commit 6ed3ebaff3345837f0528d85bd39ce573c7b9a41
	Issue introduced in 4.5 with commit 59caaed7a72a0e3750dfb84636dae6b781559310 and fixed in 7.2.8 with commit ceecf3f9c322fc6937a66682942a26ad13a34a07
	Issue introduced in 4.5 with commit 59caaed7a72a0e3750dfb84636dae6b781559310 and fixed in 7.3-rc4 with commit d85f0f0a7c85756fc992c70d869706f19dac9259

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-2026-98358
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/ulp/iser/iser_initiator.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/198e4db9add54a50cce60a5d80b8f0ee5456b65a
	https://git.kernel.org/stable/c/b9e37452915feaa8422af87dea5d0c16a7d1ff13
	https://git.kernel.org/stable/c/19ddd4af7fce9200e70882f622011e9dd130f427
	https://git.kernel.org/stable/c/9d145a2d8d6f8f2cc460b80df41870819048f2a0
	https://git.kernel.org/stable/c/b4d278c91209931199db9c0836dc2e21a7593dad
	https://git.kernel.org/stable/c/6ed3ebaff3345837f0528d85bd39ce573c7b9a41
	https://git.kernel.org/stable/c/ceecf3f9c322fc6937a66682942a26ad13a34a07
	https://git.kernel.org/stable/c/d85f0f0a7c85756fc992c70d869706f19dac9259