kernel/linux.git/drivers/crypto/ccp/ccp-debugfs.c, branch v6.12.80

crypto: ccp - Fix crash when rebind ccp device for ccp.ko

2025-08-15T10:13:53+00:00

[ Upstream commit 181698af38d3f93381229ad89c09b5bd0496661a ] When CONFIG_CRYPTO_DEV_CCP_DEBUGFS is enabled, rebinding the ccp device causes the following crash: $ echo '0000:0a:00.2' > /sys/bus/pci/drivers/ccp/unbind $ echo '0000:0a:00.2' > /sys/bus/pci/drivers/ccp/bind [ 204.976930] BUG: kernel NULL pointer dereference, address: 0000000000000098 [ 204.978026] #PF: supervisor write access in kernel mode [ 204.979126] #PF: error_code(0x0002) - not-present page [ 204.980226] PGD 0 P4D 0 [ 204.981317] Oops: Oops: 0002 [#1] SMP NOPTI ... [ 204.997852] Call Trace: [ 204.999074] [ 205.000297] start_creating+0x9f/0x1c0 [ 205.001533] debugfs_create_dir+0x1f/0x170 [ 205.002769] ? srso_return_thunk+0x5/0x5f [ 205.004000] ccp5_debugfs_setup+0x87/0x170 [ccp] [ 205.005241] ccp5_init+0x8b2/0x960 [ccp] [ 205.006469] ccp_dev_init+0xd4/0x150 [ccp] [ 205.007709] sp_init+0x5f/0x80 [ccp] [ 205.008942] sp_pci_probe+0x283/0x2e0 [ccp] [ 205.010165] ? srso_return_thunk+0x5/0x5f [ 205.011376] local_pci_probe+0x4f/0xb0 [ 205.012584] pci_device_probe+0xdb/0x230 [ 205.013810] really_probe+0xed/0x380 [ 205.015024] __driver_probe_device+0x7e/0x160 [ 205.016240] device_driver_attach+0x2f/0x60 [ 205.017457] bind_store+0x7c/0xb0 [ 205.018663] drv_attr_store+0x28/0x40 [ 205.019868] sysfs_kf_write+0x5f/0x70 [ 205.021065] kernfs_fop_write_iter+0x145/0x1d0 [ 205.022267] vfs_write+0x308/0x440 [ 205.023453] ksys_write+0x6d/0xe0 [ 205.024616] __x64_sys_write+0x1e/0x30 [ 205.025778] x64_sys_call+0x16ba/0x2150 [ 205.026942] do_syscall_64+0x56/0x1e0 [ 205.028108] entry_SYSCALL_64_after_hwframe+0x76/0x7e [ 205.029276] RIP: 0033:0x7fbc36f10104 [ 205.030420] Code: 89 02 48 c7 c0 ff ff ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 90 48 8d 05 e1 08 2e 00 8b 00 85 c0 75 13 b8 01 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 54 f3 c3 66 90 41 54 55 49 89 d4 53 48 89 f5 This patch sets ccp_debugfs_dir to NULL after destroying it in ccp5_debugfs_destroy, allowing the directory dentry to be recreated when rebinding the ccp device. Tested on AMD Ryzen 7 1700X. Fixes: 3cdbe346ed3f ("crypto: ccp - Add debugfs entries for CCP information") Signed-off-by: Mengbiao Xiong Reviewed-by: Tom Lendacky Signed-off-by: Herbert Xu Signed-off-by: Sasha Levin

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

2019-06-19T15:09:55+00:00

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation this program is free software you can redistribute it and or modify it under the terms of the gnu general public license version 2 as published by the free software foundation # extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 4122 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Enrico Weigelt Reviewed-by: Kate Stewart Reviewed-by: Allison Randal Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de Signed-off-by: Greg Kroah-Hartman

crypto: ccp - no need to check return value of debugfs_create functions

2019-02-01T06:42:03+00:00

When calling debugfs functions, there is no need to ever check the return value. The function can work or not, but the code logic should never do something different based on this. Cc: Tom Lendacky Cc: Gary Hook Cc: Herbert Xu Cc: "David S. Miller" Cc: linux-crypto@vger.kernel.org Signed-off-by: Greg Kroah-Hartman Acked-by: Gary R Hook Signed-off-by: Herbert Xu

crypto: ccp - don't disable interrupts while setting up debugfs

2018-03-02T16:03:40+00:00

I don't why we need take a single write lock and disable interrupts while setting up debugfs. This is what what happens when we try anyway: |ccp 0000:03:00.2: enabling device (0000 -> 0002) |BUG: sleeping function called from invalid context at kernel/locking/rwsem.c:69 |in_atomic(): 1, irqs_disabled(): 1, pid: 3, name: kworker/0:0 |irq event stamp: 17150 |hardirqs last enabled at (17149): [<0000000097a18c49>] restore_regs_and_return_to_kernel+0x0/0x23 |hardirqs last disabled at (17150): [<000000000773b3a9>] _raw_write_lock_irqsave+0x1b/0x50 |softirqs last enabled at (17148): [<0000000064d56155>] __do_softirq+0x3b8/0x4c1 |softirqs last disabled at (17125): [<0000000092633c18>] irq_exit+0xb1/0xc0 |CPU: 0 PID: 3 Comm: kworker/0:0 Not tainted 4.16.0-rc2+ #30 |Workqueue: events work_for_cpu_fn |Call Trace: | dump_stack+0x7d/0xb6 | ___might_sleep+0x1eb/0x250 | down_write+0x17/0x60 | start_creating+0x4c/0xe0 | debugfs_create_dir+0x9/0x100 | ccp5_debugfs_setup+0x191/0x1b0 | ccp5_init+0x8a7/0x8c0 | ccp_dev_init+0xb8/0xe0 | sp_init+0x6c/0x90 | sp_pci_probe+0x26e/0x590 | local_pci_probe+0x3f/0x90 | work_for_cpu_fn+0x11/0x20 | process_one_work+0x1ff/0x650 | worker_thread+0x1d4/0x3a0 | kthread+0xfe/0x130 | ret_from_fork+0x27/0x50 If any locking is required, a simple mutex will do it. Cc: Gary R Hook Signed-off-by: Sebastian Andrzej Siewior Acked-by: Gary R Hook Signed-off-by: Herbert Xu

crypto: ccp - Provide an error path for debugfs setup failure

2017-07-18T09:50:53+00:00

Changes since v2: - On failure remove only the DebugFS heirarchy for this device Changes since v1: - Remove unneeded local variable Signed-off-by: Gary R Hook Signed-off-by: Herbert Xu

crypto: ccp - Release locks before returning

2017-06-22T08:54:09+00:00

krobot warning: make sure that all error return paths release locks. Signed-off-by: Gary R Hook Signed-off-by: Herbert Xu

crypto: ccp - Add debugfs entries for CCP information

2017-06-19T06:11:47+00:00

Expose some data about the configuration and operation of the CCP through debugfs entries: device name, capabilities, configuration, statistics. Allow the user to reset the counters to zero by writing (any value) to the 'stats' file. This can be done per queue or per device. Changes from V1: - Correct polarity of test when destroying devices at module unload Signed-off-by: Gary R Hook Signed-off-by: Herbert Xu