/* * Kernel module for testing copy_to/from_user infrastructure. * * Copyright 2013 Google Inc. All Rights Reserved * * Authors: * Kees Cook * * This software is licensed under the terms of the GNU General Public * License version 2, as published by the Free Software Foundation, and * may be copied, distributed, and modified under those terms. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include #include #include #include #include #include #define test(condition, msg) \ ({ \ int cond = (condition); \ if (cond) \ pr_warn("%s\n", msg); \ cond; \ }) static int __init test_user_copy_init(void) { int ret = 0; char *kmem; char __user *usermem; char *bad_usermem; unsigned long user_addr; unsigned long value = 0x5A; kmem = kmalloc(PAGE_SIZE * 2, GFP_KERNEL); if (!kmem) return -ENOMEM; user_addr = vm_mmap(NULL, 0, PAGE_SIZE * 2, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_ANONYMOUS | MAP_PRIVATE, 0); if (user_addr >= (unsigned long)(TASK_SIZE)) { pr_warn("Failed to allocate user memory\n"); kfree(kmem); return -ENOMEM; } usermem = (char __user *)user_addr; bad_usermem = (char *)user_addr; /* Legitimate usage: none of these should fail. */ ret |= test(copy_from_user(kmem, usermem, PAGE_SIZE), "legitimate copy_from_user failed"); ret |= test(copy_to_user(usermem, kmem, PAGE_SIZE), "legitimate copy_to_user failed"); ret |= test(get_user(value, (unsigned long __user *)usermem), "legitimate get_user failed"); ret |= test(put_user(value, (unsigned long __user *)usermem), "legitimate put_user failed"); /* Invalid usage: none of these should succeed. */ ret |= test(!copy_from_user(kmem, (char __user *)(kmem + PAGE_SIZE), PAGE_SIZE), "illegal all-kernel copy_from_user passed"); ret |= test(!copy_from_user(bad_usermem, (char __user *)kmem, PAGE_SIZE), "illegal reversed copy_from_user passed"); ret |= test(!copy_to_user((char __user *)kmem, kmem + PAGE_SIZE, PAGE_SIZE), "illegal all-kernel copy_to_user passed"); ret |= test(!copy_to_user((char __user *)kmem, bad_usermem, PAGE_SIZE), "illegal reversed copy_to_user passed"); ret |= test(!get_user(value, (unsigned long __user *)kmem), "illegal get_user passed"); ret |= test(!put_user(value, (unsigned long __user *)kmem), "illegal put_user passed"); vm_munmap(user_addr, PAGE_SIZE * 2); kfree(kmem); if (ret == 0) { pr_info("tests passed.\n"); return 0; } return -EINVAL; } module_init(test_user_copy_init); static void __exit test_user_copy_exit(void) { pr_info("unloaded.\n"); } module_exit(test_user_copy_exit); MODULE_AUTHOR("Kees Cook "); MODULE_LICENSE("GPL"); uthorFilesLines 0468307'>drm
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authorThomas Gleixner <tglx@linutronix.de>2017-01-10 14:01:05 +0100
committerThomas Gleixner <tglx@linutronix.de>2017-01-16 13:20:05 +0100
commit4205e4786d0b9fc3b4fec7b1910cf645a0468307 (patch)
tree685ccb486409197b936c785eb9d173c3edff45a1 /include/drm
parent7e164ce4e8ecd7e9a58a83750bd3ee03125df154 (diff)
cpu/hotplug: Provide dynamic range for prepare stage
Mathieu reported that the LTTNG modules are broken as of 4.10-rc1 due to the removal of the cpu hotplug notifiers. Usually I don't care much about out of tree modules, but LTTNG is widely used in distros. There are two ways to solve that: 1) Reserve a hotplug state for LTTNG 2) Add a dynamic range for the prepare states. While #1 is the simplest solution, #2 is the proper one as we can convert in tree users, which do not care about ordering, to the dynamic range as well. Add a dynamic range which allows LTTNG to request states in the prepare stage. Reported-and-tested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Sewior <bigeasy@linutronix.de> Cc: Steven Rostedt <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/alpine.DEB.2.20.1701101353010.3401@nanos Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Diffstat (limited to 'include/drm')