CVE-2026-68291: idpf: fix max_vport related crash on allocation error during init

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

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

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

idpf: fix max_vport related crash on allocation error during init

Set adapter->max_vports only after successful allocation of vports, netdevs
and  vport_config buffers. This fixes possible crashes on reset or rmmod,
following failed allocation on init

[  305.981402] idpf 0000:83:00.0: enabling device (0100 -> 0102)
[  305.994464] idpf 0000:83:00.0: Device HW Reset initiated
[  320.416872] BUG: kernel NULL pointer dereference, address: 0000000000000000
[  320.416918] #PF: supervisor read access in kernel mode
[  320.416942] #PF: error_code(0x0000) - not-present page
[  320.416963] PGD 2099657067 P4D 0
[  320.416983] Oops: Oops: 0000 [#1] SMP NOPTI
...
[  320.417093] RIP: 0010:idpf_remove+0x118/0x200 [idpf]
[  320.417130] Code: 8b bb 98 09 00 00 e8 17 0f 5b e5 48 8b bb e8 08 00 00 e8 0b 0f 5b e5 66 83 bb 28 06 00 00 00 48 8b bb 20 06 00 00 74 49 31 ed <48> 8b 04 ef 48 85 c0 74 2f 48 8b 78 20 e8 66 58 91 e5 48 8b 83 20
[  320.417183] RSP: 0018:ff7322212903fdb8 EFLAGS: 00010246
[  320.417205] RAX: 0000000000000000 RBX: ff4463de40300000 RCX: ff7322212903fd4c
[  320.417228] RDX: 0000000000000001 RSI: ffffffffa7f7d100 RDI: 0000000000000000
[  320.417250] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
[  320.417272] R10: 0000000000000001 R11: ff4463de3a638f58 R12: ff4463be89ac7000
[  320.417294] R13: ff4463be89ac7198 R14: ff4463be94fc7198 R15: ffffffffc0f10f20
[  320.417317] FS:  00007f963c0e6740(0000) GS:ff4463fdd65d8000(0000) knlGS:0000000000000000
[  320.417342] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  320.417362] CR2: 0000000000000000 CR3: 00000020ba674002 CR4: 0000000000773ef0
[  320.417385] PKRU: 55555554
[  320.417398] Call Trace:
[  320.417412]  <TASK>
[  320.417429]  pci_device_remove+0x42/0xb0
[  320.417459]  device_release_driver_internal+0x1a9/0x210
[  320.417492]  driver_detach+0x4b/0x90
[  320.417516]  bus_remove_driver+0x70/0x100
[  320.417539]  pci_unregister_driver+0x2e/0xb0
[  320.417564]  __do_sys_delete_module.constprop.0+0x190/0x2f0
[  320.417592]  ? kmem_cache_free+0x31e/0x550
[  320.417619]  ? lockdep_hardirqs_on_prepare+0xde/0x190
[  320.417644]  ? do_syscall_64+0x38/0x6b0
[  320.417665]  do_syscall_64+0xc8/0x6b0
[  320.417683]  ? clear_bhb_loop+0x30/0x80
[  320.417706]  entry_SYSCALL_64_after_hwframe+0x76/0x7e
[  320.417727] RIP: 0033:0x7f963bb30beb

The Linux kernel CVE team has assigned CVE-2026-68291 to this issue.


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

	Issue introduced in 6.7 with commit 0fe45467a1041ea3657a7fa3a791c84c104fbd34 and fixed in 7.1.6 with commit 9fbe22b7aff0a65984d78ee6b93e2f8179abd1f5
	Issue introduced in 6.7 with commit 0fe45467a1041ea3657a7fa3a791c84c104fbd34 and fixed in 7.2-rc5 with commit 237f1f7653b8729169af11fae79f01b90d00b87e

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-2026-68291
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/net/ethernet/intel/idpf/idpf_virtchnl.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/9fbe22b7aff0a65984d78ee6b93e2f8179abd1f5
	https://git.kernel.org/stable/c/237f1f7653b8729169af11fae79f01b90d00b87e