[PATCH net] i40e: Fix kernel crash during reboot when adapter is in recovery mode

[Ivan Vecera]

If the driver detects during probe that firmware is in recovery
mode then i40e_init_recovery_mode() is called and the rest of
probe function is skipped including pci_set_drvdata(). Subsequent
i40e_shutdown() called during shutdown/reboot dereferences NULL
pointer as pci_get_drvdata() returns NULL.

To fix call pci_set_drvdata() also during entering to recovery mode.

Reproducer:
1) Lets have i40e NIC with firmware in recovery mode
2) Run reboot

Result:
[  139.084698] i40e: Intel(R) Ethernet Connection XL710 Network Driver
[  139.090959] i40e: Copyright (c) 2013 - 2019 Intel Corporation.
[  139.108438] i40e 0000:02:00.0: Firmware recovery mode detected. Limiting functionality.
[  139.116439] i40e 0000:02:00.0: Refer to the Intel(R) Ethernet Adapters and Devices User Guide for details on firmware recovery mode.
[  139.129499] i40e 0000:02:00.0: fw 8.3.64775 api 1.13 nvm 8.30 0x8000b78d 1.3106.0 [8086:1583] [15d9:084a]
[  139.215932] i40e 0000:02:00.0 enp2s0f0: renamed from eth0
[  139.223292] i40e 0000:02:00.1: Firmware recovery mode detected. Limiting functionality.
[  139.231292] i40e 0000:02:00.1: Refer to the Intel(R) Ethernet Adapters and Devices User Guide for details on firmware recovery mode.
[  139.244406] i40e 0000:02:00.1: fw 8.3.64775 api 1.13 nvm 8.30 0x8000b78d 1.3106.0 [8086:1583] [15d9:084a]
[  139.329209] i40e 0000:02:00.1 enp2s0f1: renamed from eth0
...
[  156.311376] BUG: kernel NULL pointer dereference, address: 00000000000006c2
[  156.318330] #PF: supervisor write access in kernel mode
[  156.323546] #PF: error_code(0x0002) - not-present page
[  156.328679] PGD 0 P4D 0
[  156.331210] Oops: 0002 [#1] PREEMPT SMP NOPTI
[  156.335567] CPU: 26 PID: 15119 Comm: reboot Tainted: G            E      6.2.0+ #1
[  156.343126] Hardware name: Abacus electric, s.r.o. - servis@xxxxxxxxx Super Server/H12SSW-iN, BIOS 2.4 04/13/2022
[  156.353369] RIP: 0010:i40e_shutdown+0x15/0x130 [i40e]
[  156.358430] Code: c1 fc ff ff 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa 0f 1f 44 00 00 55 48 89 fd 53 48 8b 9f 48 01 00 00 <f0> 80 8b c2 06 00 00 04 f0 80 8b c0 06 00 00 08 48 8d bb 08 08 00
[  156.377168] RSP: 0018:ffffb223c8447d90 EFLAGS: 00010282
[  156.382384] RAX: ffffffffc073ee70 RBX: 0000000000000000 RCX: 0000000000000001
[  156.389510] RDX: 0000000080000001 RSI: 0000000000000246 RDI: ffff95db49988000
[  156.396634] RBP: ffff95db49988000 R08: ffffffffffffffff R09: ffffffff8bd17d40
[  156.403759] R10: 0000000000000001 R11: ffffffff8a5e3d28 R12: ffff95db49988000
[  156.410882] R13: ffffffff89a6fe17 R14: ffff95db49988150 R15: 0000000000000000
[  156.418007] FS:  00007fe7c0cc3980(0000) GS:ffff95ea8ee80000(0000) knlGS:0000000000000000
[  156.426083] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  156.431819] CR2: 00000000000006c2 CR3: 00000003092fc005 CR4: 0000000000770ee0
[  156.438944] PKRU: 55555554
[  156.441647] Call Trace:
[  156.444096]  <TASK>
[  156.446199]  pci_device_shutdown+0x38/0x60
[  156.450297]  device_shutdown+0x163/0x210
[  156.454215]  kernel_restart+0x12/0x70
[  156.457872]  __do_sys_reboot+0x1ab/0x230
[  156.461789]  ? vfs_writev+0xa6/0x1a0
[  156.465362]  ? __pfx_file_free_rcu+0x10/0x10
[  156.469635]  ? __call_rcu_common.constprop.85+0x109/0x5a0
[  156.475034]  do_syscall_64+0x3e/0x90
[  156.478611]  entry_SYSCALL_64_after_hwframe+0x72/0xdc
[  156.483658] RIP: 0033:0x7fe7bff37ab7

Fixes: 4ff0ee1af01697 ("i40e: Introduce recovery mode support")
Signed-off-by: Ivan Vecera <ivecera@xxxxxxxxxx>
---
 drivers/net/ethernet/intel/i40e/i40e_main.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 467001db5070ed..228cd502bb48a9 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -15525,6 +15525,7 @@ static int i40e_init_recovery_mode(struct i40e_pf *pf, struct i40e_hw *hw)
 	int err;
 	int v_idx;
 
+	pci_set_drvdata(pf->pdev, pf);
 	pci_save_state(pf->pdev);
 
 	/* set up periodic task facility */
-- 
2.39.2