Re: [PATCH iwl-net] idpf: fix max_vport related crash on allocation error during init

[Simon Horman <horms@kernel.org>]

On Thu, Jun 18, 2026 at 12:23:25PM -0700, Emil Tantilov wrote:
> 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
> 
> Fixes: 0fe45467a104 ("idpf: add create vport and netdev configuration")
> Reviewed-by: Madhu Chittim <madhu.chittim@intel.com>
> Signed-off-by: Emil Tantilov <emil.s.tantilov@intel.com>

Reviewed-by: Simon Horman <horms@kernel.org>

FTR, an AI generated review of this patch is available on sashiko.dev.
I think that the issue raised there can be looked at in the context of
possible follow-up.