[PATCH 5.14 029/334] crypto: omap - Fix inconsistent locking of device lists

Greg Kroah-Hartman
2021-09-13T14:27:32Z

From: Ben Hutchings <ben.hutchings@mind.be>

[ Upstream commit fe4d55773b879c785ae61da9b1c2160f0110f67e ]

lockdep complains that in omap-aes, the list_lock is taken both with
softirqs enabled at probe time, and also in softirq context, which
could lead to a deadlock:

================================
WARNING: inconsistent lock state
5.14.0-rc1-00035-gc836005b01c5-dirty #69 Not tainted
--------------------------------
inconsistent {SOFTIRQ-ON-W} -> {IN-SOFTIRQ-W} usage.
ksoftirqd/0/7 [HC0[0]:SC1[3]:HE1:SE0] takes:
bf00e014 (list_lock){+.?.}-{2:2}, at: omap_aes_find_dev+0x18/0x54 [omap_aes_driver]
{SOFTIRQ-ON-W} state was registered at:
_raw_spin_lock+0x40/0x50
omap_aes_probe+0x1d4/0x664 [omap_aes_driver]
platform_probe+0x58/0xb8
really_probe+0xbc/0x314
__driver_probe_device+0x80/0xe4
driver_probe_device+0x30/0xc8
__driver_attach+0x70/0xf4
bus_for_each_dev+0x70/0xb4
bus_add_driver+0xf0/0x1d4
driver_register+0x74/0x108
do_one_initcall+0x84/0x2e4
do_init_module+0x5c/0x240
load_module+0x221c/0x2584
sys_finit_module+0xb0/0xec
ret_fast_syscall+0x0/0x2c
0xbed90b30
irq event stamp: 111800
hardirqs last enabled at (111800): [<c02a21e4>] __kmalloc+0x484/0x5ec
hardirqs last disabled at (111799): [<c02a21f0>] __kmalloc+0x490/0x5ec
softirqs last enabled at (111776): [<c01015f0>] __do_softirq+0x2b8/0x4d0
softirqs last disabled at (111781): [<c0135948>] run_ksoftirqd+0x34/0x50

other info that might help us debug this:
Possible unsafe locking scenario:

CPU0
----
lock(list_lock);
<Interrupt>
lock(list_lock);

*** DEADLOCK ***

2 locks held by ksoftirqd/0/7:
#0: c0f5e8c8 (rcu_read_lock){....}-{1:2}, at: netif_receive_skb+0x6c/0x260
#1: c0f5e8c8 (rcu_read_lock){....}-{1:2}, at: ip_local_deliver_finish+0x2c/0xdc

stack backtrace:
CPU: 0 PID: 7 Comm: ksoftirqd/0 Not tainted 5.14.0-rc1-00035-gc836005b01c5-dirty #69
Hardware name: Generic AM43 (Flattened Device Tree)
[<c010e6e0>] (unwind_backtrace) from [<c010b9d0>] (show_stack+0x10/0x14)
[<c010b9d0>] (show_stack) from [<c017c640>] (mark_lock.part.17+0x5bc/0xd04)
[<c017c640>] (mark_lock.part.17) from [<c017d9e4>] (__lock_acquire+0x960/0x2fa4)
[<c017d9e4>] (__lock_acquire) from [<c0180980>] (lock_acquire+0x10c/0x358)
[<c0180980>] (lock_acquire) from [<c093d324>] (_raw_spin_lock_bh+0x44/0x58)
[<c093d324>] (_raw_spin_lock_bh) from [<bf00b258>] (omap_aes_find_dev+0x18/0x54 [omap_aes_driver])
[<bf00b258>] (omap_aes_find_dev [omap_aes_driver]) from [<bf00b328>] (omap_aes_crypt+0x94/0xd4 [omap_aes_driver])
[<bf00b328>] (omap_aes_crypt [omap_aes_driver]) from [<c08ac6d0>] (esp_input+0x1b0/0x2c8)
[<c08ac6d0>] (esp_input) from [<c08c9e90>] (xfrm_input+0x410/0x1290)
[<c08c9e90>] (xfrm_input) from [<c08b6374>] (xfrm4_esp_rcv+0x54/0x11c)
[<c08b6374>] (xfrm4_esp_rcv) from [<c0838840>] (ip_protocol_deliver_rcu+0x48/0x3bc)
[<c0838840>] (ip_protocol_deliver_rcu) from [<c0838c50>] (ip_local_deliver_finish+0x9c/0xdc)
[<c0838c50>] (ip_local_deliver_finish) from [<c0838dd8>] (ip_local_deliver+0x148/0x1b0)
[<c0838dd8>] (ip_local_deliver) from [<c0838f5c>] (ip_rcv+0x11c/0x180)
[<c0838f5c>] (ip_rcv) from [<c077e3a4>] (__netif_receive_skb_one_core+0x54/0x74)
[<c077e3a4>] (__netif_receive_skb_one_core) from [<c077e588>] (netif_receive_skb+0xa8/0x260)
[<c077e588>] (netif_receive_skb) from [<c068d6d4>] (cpsw_rx_handler+0x224/0x2fc)
[<c068d6d4>] (cpsw_rx_handler) from [<c0688ccc>] (__cpdma_chan_process+0xf4/0x188)
[<c0688ccc>] (__cpdma_chan_process) from [<c068a0c0>] (cpdma_chan_process+0x3c/0x5c)
[<c068a0c0>] (cpdma_chan_process) from [<c0690e14>] (cpsw_rx_mq_poll+0x44/0x98)
[<c0690e14>] (cpsw_rx_mq_poll) from [<c0780810>] (__napi_poll+0x28/0x268)
[<c0780810>] (__napi_poll) from [<c0780c64>] (net_rx_action+0xcc/0x204)
[<c0780c64>] (net_rx_action) from [<c0101478>] (__do_softirq+0x140/0x4d0)
[<c0101478>] (__do_softirq) from [<c0135948>] (run_ksoftirqd+0x34/0x50)
[<c0135948>] (run_ksoftirqd) from [<c01583b8>] (smpboot_thread_fn+0xf4/0x1d8)
[<c01583b8>] (smpboot_thread_fn) from [<c01546dc>] (kthread+0x14c/0x174)
[<c01546dc>] (kthread) from [<c010013c>] (ret_from_fork+0x14/0x38)
...

The omap-des and omap-sham drivers appear to have a similar issue.

Fix this by using spin_{,un}lock_bh() around device list access in all
the probe and remove functions.

Signed-off-by: Ben Hutchings <ben.hutchings@mind.be>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/crypto/omap-aes.c | 8 ++++----
drivers/crypto/omap-des.c | 8 ++++----
drivers/crypto/omap-sham.c | 12 ++++++------
3 files changed, 14 insertions(+), 14 deletions(-)

diff --git a/drivers/crypto/omap-aes.c b/drivers/crypto/omap-aes.c
index 0dd4c6b157de..9b968ac4ee7b 100644
--- a/drivers/crypto/omap-aes.c
+++ b/drivers/crypto/omap-aes.c
@@ -1175,9 +1175,9 @@ static int omap_aes_probe(struct platform_device *pdev)
spin_lock_init(&dd->lock);

INIT_LIST_HEAD(&dd->list);
- spin_lock(&list_lock);
+ spin_lock_bh(&list_lock);
list_add_tail(&dd->list, &dev_list);
- spin_unlock(&list_lock);
+ spin_unlock_bh(&list_lock);

/* Initialize crypto engine */
dd->engine = crypto_engine_alloc_init(dev, 1);
@@ -1264,9 +1264,9 @@ static int omap_aes_remove(struct platform_device *pdev)
if (!dd)
return -ENODEV;

- spin_lock(&list_lock);
+ spin_lock_bh(&list_lock);
list_del(&dd->list);
- spin_unlock(&list_lock);
+ spin_unlock_bh(&list_lock);

for (i = dd->pdata->algs_info_size - 1; i >= 0; i--)
for (j = dd->pdata->algs_info[i].registered - 1; j >= 0; j--) {
diff --git a/drivers/crypto/omap-des.c b/drivers/crypto/omap-des.c
index bc8631363d72..be77656864e3 100644
--- a/drivers/crypto/omap-des.c
+++ b/drivers/crypto/omap-des.c
@@ -1033,9 +1033,9 @@ static int omap_des_probe(struct platform_device *pdev)

INIT_LIST_HEAD(&dd->list);
- spin_lock(&list_lock);
+ spin_lock_bh(&list_lock);
list_add_tail(&dd->list, &dev_list);
- spin_unlock(&list_lock);
+ spin_unlock_bh(&list_lock);

/* Initialize des crypto engine */
dd->engine = crypto_engine_alloc_init(dev, 1);
@@ -1094,9 +1094,9 @@ static int omap_des_remove(struct platform_device *pdev)
if (!dd)
return -ENODEV;

- spin_lock(&list_lock);
+ spin_lock_bh(&list_lock);
list_del(&dd->list);
- spin_unlock(&list_lock);
+ spin_unlock_bh(&list_lock);

for (i = dd->pdata->algs_info_size - 1; i >= 0; i--)
for (j = dd->pdata->algs_info[i].registered - 1; j >= 0; j--)
diff --git a/drivers/crypto/omap-sham.c b/drivers/crypto/omap-sham.c
index a47ac60a4ee1..63beea7cdba5 100644
--- a/drivers/crypto/omap-sham.c
+++ b/drivers/crypto/omap-sham.c
@@ -2144,9 +2144,9 @@ static int omap_sham_probe(struct platform_device *pdev)
(rev & dd->pdata->major_mask) >> dd->pdata->major_shift,
(rev & dd->pdata->minor_mask) >> dd->pdata->minor_shift);

- spin_lock(&sham.lock);
+ spin_lock_bh(&sham.lock);
list_add_tail(&dd->list, &sham.dev_list);
- spin_unlock(&sham.lock);
+ spin_unlock_bh(&sham.lock);

dd->engine = crypto_engine_alloc_init(dev, 1);
if (!dd->engine) {
@@ -2194,9 +2194,9 @@ err_algs:
err_engine_start:
crypto_engine_exit(dd->engine);
err_engine:
- spin_lock(&sham.lock);
+ spin_lock_bh(&sham.lock);
list_del(&dd->list);
- spin_unlock(&sham.lock);
+ spin_unlock_bh(&sham.lock);
err_pm:
pm_runtime_disable(dev);
if (!dd->polling_mode)
@@ -2215,9 +2215,9 @@ static int omap_sham_remove(struct platform_device *pdev)
dd = platform_get_drvdata(pdev);
if (!dd)
return -ENODEV;
- spin_lock(&sham.lock);
+ spin_lock_bh(&sham.lock);
list_del(&dd->list);
- spin_unlock(&sham.lock);
+ spin_unlock_bh(&sham.lock);
for (i = dd->pdata->algs_info_size - 1; i >= 0; i--)
for (j = dd->pdata->algs_info[i].registered - 1; j >= 0; j--) {
crypto_unregister_ahash(
--
2.30.2