idpf: fix UAF in RDMA core aux dev deinitialization

Free the adev->id before auxiliary_device_uninit. The call to uninit
triggers the release callback, which frees the iadev memory containing the
adev. The previous flow results in a UAF during rmmod due to the adev->id
access.

[264939.604077] ==================================================================
[264939.604093] BUG: KASAN: slab-use-after-free in idpf_idc_deinit_core_aux_device+0xe4/0x100 [idpf]
[264939.604134] Read of size 4 at addr ff1100109eb6eaf8 by task rmmod/17842

...

[264939.604635] Allocated by task 17597:
[264939.604643]  kasan_save_stack+0x20/0x40
[264939.604654]  kasan_save_track+0x14/0x30
[264939.604663]  __kasan_kmalloc+0x8f/0xa0
[264939.604672]  idpf_idc_init_aux_core_dev+0x4bd/0xb60 [idpf]
[264939.604700]  idpf_idc_init+0x55/0xd0 [idpf]
[264939.604726]  process_one_work+0x658/0xfe0
[264939.604742]  worker_thread+0x6e1/0xf10
[264939.604750]  kthread+0x382/0x740
[264939.604762]  ret_from_fork+0x23a/0x310
[264939.604772]  ret_from_fork_asm+0x1a/0x30

[264939.604785] Freed by task 17842:
[264939.604790]  kasan_save_stack+0x20/0x40
[264939.604799]  kasan_save_track+0x14/0x30
[264939.604808]  kasan_save_free_info+0x3b/0x60
[264939.604820]  __kasan_slab_free+0x37/0x50
[264939.604830]  kfree+0xf1/0x420
[264939.604840]  device_release+0x9c/0x210
[264939.604850]  kobject_put+0x17c/0x4b0
[264939.604860]  idpf_idc_deinit_core_aux_device+0x4f/0x100 [idpf]
[264939.604886]  idpf_vc_core_deinit+0xba/0x3a0 [idpf]
[264939.604915]  idpf_remove+0xb0/0x7c0 [idpf]
[264939.604944]  pci_device_remove+0xab/0x1e0
[264939.604955]  device_release_driver_internal+0x371/0x530
[264939.604969]  driver_detach+0xbf/0x180
[264939.604981]  bus_remove_driver+0x11b/0x2a0
[264939.604991]  pci_unregister_driver+0x2a/0x250
[264939.605005]  __do_sys_delete_module.constprop.0+0x2eb/0x540
[264939.605014]  do_syscall_64+0x64/0x2c0
[264939.605024]  entry_SYSCALL_64_after_hwframe+0x76/0x7e

Fixes: f4312e6 ("idpf: implement core RDMA auxiliary dev create, init, and destroy")
Signed-off-by: Joshua Hay <[email protected]>
Reviewed-by: Aleksandr Loktionov <[email protected]>
Reviewed-by: Vadim Fedorenko <[email protected]>
Tested-by: Samuel Salin <[email protected]>
Reviewed-by: Jacob Keller <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>

Author: jahay1

drivers/net/ethernet/intel/idpf/idpf_idc.c

@@ -247,10 +247,10 @@ static void idpf_unplug_aux_dev(struct auxiliary_device *adev)
 	if (!adev)
 		return;
 
+	ida_free(&idpf_idc_ida, adev->id);
+
 	auxiliary_device_delete(adev);
 	auxiliary_device_uninit(adev);
-
-	ida_free(&idpf_idc_ida, adev->id);
 }
 
 /**