Subject: CVE-2021-47284: isdn: mISDN: netjet: Fix crash in nj_probe:

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

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

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

isdn: mISDN: netjet: Fix crash in nj_probe:

'nj_setup' in netjet.c might fail with -EIO and in this case
'card->irq' is initialized and is bigger than zero. A subsequent call to
'nj_release' will free the irq that has not been requested.

Fix this bug by deleting the previous assignment to 'card->irq' and just
keep the assignment before 'request_irq'.

The KASAN's log reveals it:

[    3.354615 ] WARNING: CPU: 0 PID: 1 at kernel/irq/manage.c:1826
free_irq+0x100/0x480
[    3.355112 ] Modules linked in:
[    3.355310 ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted
5.13.0-rc1-00144-g25a1298726e #13
[    3.355816 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
[    3.356552 ] RIP: 0010:free_irq+0x100/0x480
[    3.356820 ] Code: 6e 08 74 6f 4d 89 f4 e8 5e ac 09 00 4d 8b 74 24 18
4d 85 f6 75 e3 e8 4f ac 09 00 8b 75 c8 48 c7 c7 78 c1 2e 85 e8 e0 cf f5
ff <0f> 0b 48 8b 75 c0 4c 89 ff e8 72 33 0b 03 48 8b 43 40 4c 8b a0 80
[    3.358012 ] RSP: 0000:ffffc90000017b48 EFLAGS: 00010082
[    3.358357 ] RAX: 0000000000000000 RBX: ffff888104dc8000 RCX:
0000000000000000
[    3.358814 ] RDX: ffff8881003c8000 RSI: ffffffff8124a9e6 RDI:
00000000ffffffff
[    3.359272 ] RBP: ffffc90000017b88 R08: 0000000000000000 R09:
0000000000000000
[    3.359732 ] R10: ffffc900000179f0 R11: 0000000000001d04 R12:
0000000000000000
[    3.360195 ] R13: ffff888107dc6000 R14: ffff888107dc6928 R15:
ffff888104dc80a8
[    3.360652 ] FS:  0000000000000000(0000) GS:ffff88817bc00000(0000)
knlGS:0000000000000000
[    3.361170 ] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[    3.361538 ] CR2: 0000000000000000 CR3: 000000000582e000 CR4:
00000000000006f0
[    3.362003 ] DR0: 0000000000000000 DR1: 0000000000000000 DR2:
0000000000000000
[    3.362175 ] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7:
0000000000000400
[    3.362175 ] Call Trace:
[    3.362175 ]  nj_release+0x51/0x1e0
[    3.362175 ]  nj_probe+0x450/0x950
[    3.362175 ]  ? pci_device_remove+0x110/0x110
[    3.362175 ]  local_pci_probe+0x45/0xa0
[    3.362175 ]  pci_device_probe+0x12b/0x1d0
[    3.362175 ]  really_probe+0x2a9/0x610
[    3.362175 ]  driver_probe_device+0x90/0x1d0
[    3.362175 ]  ? mutex_lock_nested+0x1b/0x20
[    3.362175 ]  device_driver_attach+0x68/0x70
[    3.362175 ]  __driver_attach+0x124/0x1b0
[    3.362175 ]  ? device_driver_attach+0x70/0x70
[    3.362175 ]  bus_for_each_dev+0xbb/0x110
[    3.362175 ]  ? rdinit_setup+0x45/0x45
[    3.362175 ]  driver_attach+0x27/0x30
[    3.362175 ]  bus_add_driver+0x1eb/0x2a0
[    3.362175 ]  driver_register+0xa9/0x180
[    3.362175 ]  __pci_register_driver+0x82/0x90
[    3.362175 ]  ? w6692_init+0x38/0x38
[    3.362175 ]  nj_init+0x36/0x38
[    3.362175 ]  do_one_initcall+0x7f/0x3d0
[    3.362175 ]  ? rdinit_setup+0x45/0x45
[    3.362175 ]  ? rcu_read_lock_sched_held+0x4f/0x80
[    3.362175 ]  kernel_init_freeable+0x2aa/0x301
[    3.362175 ]  ? rest_init+0x2c0/0x2c0
[    3.362175 ]  kernel_init+0x18/0x190
[    3.362175 ]  ? rest_init+0x2c0/0x2c0
[    3.362175 ]  ? rest_init+0x2c0/0x2c0
[    3.362175 ]  ret_from_fork+0x1f/0x30
[    3.362175 ] Kernel panic - not syncing: panic_on_warn set ...
[    3.362175 ] CPU: 0 PID: 1 Comm: swapper/0 Not tainted
5.13.0-rc1-00144-g25a1298726e #13
[    3.362175 ] Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS
rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
[    3.362175 ] Call Trace:
[    3.362175 ]  dump_stack+0xba/0xf5
[    3.362175 ]  ? free_irq+0x100/0x480
[    3.362175 ]  panic+0x15a/0x3f2
[    3.362175 ]  ? __warn+0xf2/0x150
[    3.362175 ]  ? free_irq+0x100/0x480
[    3.362175 ]  __warn+0x108/0x150
[    3.362175 ]  ? free_irq+0x100/0x480
[    3.362175 ]  report_bug+0x119/0x1c0
[    3.362175 ]  handle_bug+0x3b/0x80
[    3.362175 ]  exc_invalid_op+0x18/0x70
[    3.362175 ]  asm_exc_invalid_op+0x12/0x20
[    3.362175 ] RIP: 0010:free_irq+0x100/0x480
[    3.362175 ] Code: 6e 08 74 6f 4d 89 f4 e8 5e ac 09 00 4d 8b 74 24 18
4d 85 f6 75 e3 e8 4f ac 09 00 8b 75 c8 48 c7 c7 78 c1 2e 85 e8 e0 cf f5
ff <0f> 0b 48 8b 75 c0 4c 89 ff e8 72 33 0b 03 48 8b 43 40 4c 8b a0 80
[    3.362175 ] RSP: 0000:ffffc90000017b48 EFLAGS: 00010082
[    3.362175 ] RAX: 0000000000000000 RBX: ffff888104dc8000 RCX:
0000000000000000
[    3.362175 ] RDX: ffff8881003c8000 RSI: ffffffff8124a9e6 RDI:
00000000ffffffff
[    3.362175 ] RBP: ffffc90000017b88 R08: 0000000000000000 R09:
0000000000000000
[    3.362175 ] R10: ffffc900000179f0 R11: 0000000000001d04 R12:
0000000000000000
[    3.362175 ] R13: ffff888107dc6000 R14: ffff888107dc6928 R15:
ffff888104dc80a8
[    3.362175 ]  ? vprintk+0x76/0x150
[    3.362175 ]  ? free_irq+0x100/0x480
[    3.362175 ]  nj_release+0x51/0x1e0
[    3.362175 ]  nj_probe+0x450/0x950
[    3.362175 ]  ? pci_device_remove+0x110/0x110
[    3.362175 ]  local_pci_probe+0x45/0xa0
[    3.362175 ]  pci_device_probe+0x12b/0x1d0
[    3.362175 ]  really_probe+0x2a9/0x610
[    3.362175 ]  driver_probe_device+0x90/0x1d0
[    3.362175 ]  ? mutex_lock_nested+0x1b/0x20
[    3.362175 ]  device_driver_attach+0x68/0x70
[    3.362175 ]  __driver_attach+0x124/0x1b0
[    3.362175 ]  ? device_driver_attach+0x70/0x70
[    3.362175 ]  bus_for_each_dev+0xbb/0x110
[    3.362175 ]  ? rdinit_setup+0x45/0x45
[    3.362175 ]  driver_attach+0x27/0x30
[    3.362175 ]  bus_add_driver+0x1eb/0x2a0
[    3.362175 ]  driver_register+0xa9/0x180
[    3.362175 ]  __pci_register_driver+0x82/0x90
[    3.362175 ]  ? w6692_init+0x38/0x38
[    3.362175 ]  nj_init+0x36/0x38
[    3.362175 ]  do_one_initcall+0x7f/0x3d0
[    3.362175 ]  ? rdinit_setup+0x45/0x45
[    3.362175 ]  ? rcu_read_lock_sched_held+0x4f/0x80
[    3.362175 ]  kernel_init_freeable+0x2aa/0x301
[    3.362175 ]  ? rest_init+0x2c0/0x2c0
[    3.362175 ]  kernel_init+0x18/0x190
[    3.362175 ]  ? rest_init+0x2c0/0x2c0
[    3.362175 ]  ? rest_init+0x2c0/0x2c0
[    3.362175 ]  ret_from_fork+0x1f/0x30
[    3.362175 ] Dumping ftrace buffer:
[    3.362175 ]    (ftrace buffer empty)
[    3.362175 ] Kernel Offset: disabled
[    3.362175 ] Rebooting in 1 seconds..

The Linux kernel CVE team has assigned CVE-2021-47284 to this issue.

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

	Fixed in 4.4.273 with commit 958cb1078ca6
	Fixed in 4.9.273 with commit 4c1fcb6ec964
	Fixed in 4.14.237 with commit a0a37e4454ca
	Fixed in 4.19.195 with commit bf78e25bd3f4
	Fixed in 5.4.126 with commit 9d7d4649dc1c
	Fixed in 5.10.44 with commit 143fc7220961
	Fixed in 5.12.11 with commit 6249193e0370
	Fixed in 5.13 with commit 9f6f852550d0

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-2021-47284
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/isdn/hardware/mISDN/netjet.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/958cb1078ca60d214826fd90a0961a447fade59a
	https://git.kernel.org/stable/c/4c1fcb6ec964b44edbf84235134582a5ffae1521
	https://git.kernel.org/stable/c/a0a37e4454ca1c0b424edc2c9c2487c2c46a1be6
	https://git.kernel.org/stable/c/bf78e25bd3f487208e042c67c8a31706c2dba265
	https://git.kernel.org/stable/c/9d7d4649dc1c53acf76df260fd519db698ed20d7
	https://git.kernel.org/stable/c/143fc7220961220eecc04669e5909af8847bf8c8
	https://git.kernel.org/stable/c/6249193e03709ea625e10706ecaf17fea0427d3d
	https://git.kernel.org/stable/c/9f6f852550d0e1b7735651228116ae9d300f69b3