cregit-Linux how code gets into the kernel

Release 4.7 include/linux/uaccess.h

Directory: include/linux
#ifndef __LINUX_UACCESS_H__

#define __LINUX_UACCESS_H__

#include <linux/sched.h>
#include <asm/uaccess.h>


static __always_inline void pagefault_disabled_inc(void) { current->pagefault_disabled++; }

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david hildenbranddavid hildenbrand14100.00%1100.00%
Total14100.00%1100.00%


static __always_inline void pagefault_disabled_dec(void) { current->pagefault_disabled--; WARN_ON(current->pagefault_disabled < 0); }

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david hildenbranddavid hildenbrand23100.00%1100.00%
Total23100.00%1100.00%

/* * These routines enable/disable the pagefault handler. If disabled, it will * not take any locks and go straight to the fixup table. * * User access methods will not sleep when called from a pagefault_disabled() * environment. */
static inline void pagefault_disable(void) { pagefault_disabled_inc(); /* * make sure to have issued the store before a pagefault * can hit. */ barrier(); }

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peter zijlstrapeter zijlstra1381.25%150.00%
david hildenbranddavid hildenbrand318.75%150.00%
Total16100.00%2100.00%


static inline void pagefault_enable(void) { /* * make sure to issue those last loads/stores before enabling * the pagefault handler again. */ barrier(); pagefault_disabled_dec(); }

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peter zijlstrapeter zijlstra1381.25%150.00%
david hildenbranddavid hildenbrand318.75%150.00%
Total16100.00%2100.00%

/* * Is the pagefault handler disabled? If so, user access methods will not sleep. */ #define pagefault_disabled() (current->pagefault_disabled != 0) /* * The pagefault handler is in general disabled by pagefault_disable() or * when in irq context (via in_atomic()). * * This function should only be used by the fault handlers. Other users should * stick to pagefault_disabled(). * Please NEVER use preempt_disable() to disable the fault handler. With * !CONFIG_PREEMPT_COUNT, this is like a NOP. So the handler won't be disabled. * in_atomic() will report different values based on !CONFIG_PREEMPT_COUNT. */ #define faulthandler_disabled() (pagefault_disabled() || in_atomic()) #ifndef ARCH_HAS_NOCACHE_UACCESS
static inline unsigned long __copy_from_user_inatomic_nocache(void *to, const void __user *from, unsigned long n) { return __copy_from_user_inatomic(to, from, n); }

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hiro yoshiokahiro yoshioka32100.00%1100.00%
Total32100.00%1100.00%


static inline unsigned long __copy_from_user_nocache(void *to, const void __user *from, unsigned long n) { return __copy_from_user(to, from, n); }

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hiro yoshiokahiro yoshioka32100.00%1100.00%
Total32100.00%1100.00%

#endif /* ARCH_HAS_NOCACHE_UACCESS */ /* * probe_kernel_read(): safely attempt to read from a location * @dst: pointer to the buffer that shall take the data * @src: address to read from * @size: size of the data chunk * * Safely read from address @src to the buffer at @dst. If a kernel fault * happens, handle that and return -EFAULT. */ extern long probe_kernel_read(void *dst, const void *src, size_t size); extern long __probe_kernel_read(void *dst, const void *src, size_t size); /* * probe_kernel_write(): safely attempt to write to a location * @dst: address to write to * @src: pointer to the data that shall be written * @size: size of the data chunk * * Safely write to address @dst from the buffer at @src. If a kernel fault * happens, handle that and return -EFAULT. */ extern long notrace probe_kernel_write(void *dst, const void *src, size_t size); extern long notrace __probe_kernel_write(void *dst, const void *src, size_t size); extern long strncpy_from_unsafe(char *dst, const void *unsafe_addr, long count); /** * probe_kernel_address(): safely attempt to read from a location * @addr: address to read from * @retval: read into this variable * * Returns 0 on success, or -EFAULT. */ #define probe_kernel_address(addr, retval) \ probe_kernel_read(&retval, addr, sizeof(retval)) #ifndef user_access_begin #define user_access_begin() do { } while (0) #define user_access_end() do { } while (0) #define unsafe_get_user(x, ptr) __get_user(x, ptr) #define unsafe_put_user(x, ptr) __put_user(x, ptr) #endif #endif /* __LINUX_UACCESS_H__ */

Overall Contributors

PersonTokensPropCommitsCommitProp
hiro yoshiokahiro yoshioka8227.33%19.09%
david hildenbranddavid hildenbrand5919.67%327.27%
jason wesseljason wessel3411.33%19.09%
ingo molnaringo molnar3411.33%19.09%
linus torvaldslinus torvalds3311.00%19.09%
peter zijlstrapeter zijlstra268.67%19.09%
alexei starovoitovalexei starovoitov175.67%19.09%
andrew mortonandrew morton113.67%19.09%
steven rostedtsteven rostedt41.33%19.09%
Total300100.00%11100.00%
Directory: include/linux
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