libc.h File Reference

#include <ntifs.h>

Go to the source code of this file.

Functions
EXTERN_C	__drv_when (return!=0, __drv_allocatesMem(pBlock)) __checkReturn __drv_maxIRQL(DISPATCH_LEVEL) __bcount_opt(size) void *__cdecl malloc(__in size_t size)
EXTERN_C	__drv_when (return !=0, __drv_allocatesMem(p)) __checkReturn __drv_maxIRQL(DISPATCH_LEVEL) __bcount_opt(size *n) void *__cdecl calloc(size_t n
EXTERN_C	__drv_when (return!=0, __drv_allocatesMem(inblock)) __checkReturn __drv_maxIRQL(DISPATCH_LEVEL) __bcount_opt(size) void *__cdecl realloc(__in_opt void *ptr
EXTERN_C	__drv_maxIRQL (DISPATCH_LEVEL) void __cdecl free(__inout_opt __drv_freesMem(Mem) void *ptr)
int __cdecl	vsnprintf (char *buffer, size_t count, const char *format, va_list argptr)

Variables
EXTERN_C size_t	size

Detailed Description

Author

created by: Peter Hlavaty

Definition in file libc.h.

Function Documentation

__drv_maxIRQL()

EXTERN_C __drv_maxIRQL

(

DISPATCH_LEVEL

)

Definition at line 101 of file libc.cpp.

{
    if (ptr)
        ExFreePoolWithTag(CONTAINING_RECORD(ptr, MEMBLOCK, data), _LIBC_POOL_TAG);
}

References _LIBC_POOL_TAG.

__drv_when() [1/3]

EXTERN_C __drv_when	(	return !	= 0,
		__drv_allocatesMem(p)
	)

__drv_when() [2/3]

EXTERN_C __drv_when	(	return!	= 0,
		__drv_allocatesMem(inblock)
	)

__drv_when() [3/3]

EXTERN_C __drv_when	(	return!	= 0,
		__drv_allocatesMem(pBlock)
	)

Definition at line 29 of file libc.cpp.

{
    /* A specially crafted size value can trigger the overflow.
    If the sum in a value that overflows or underflows the capacity of the type,
    the function returns nullptr. */
    size_t number_of_bytes = 0;
    if (!NT_SUCCESS(RtlSizeTAdd(size, sizeof(MEMBLOCK), &number_of_bytes))){
        return nullptr;
    }
    MEMBLOCK *pBlock = static_cast<MEMBLOCK*>(
        ExAllocatePoolWithTag(
            NonPagedPoolNxCacheAligned, 
            number_of_bytes, 
            _LIBC_POOL_TAG));
 
    if (nullptr == pBlock)
        return nullptr;
 
    pBlock->size = size;    
    return pBlock->data;
}

References _LIBC_POOL_TAG, ExAllocatePoolWithTag, NT_SUCCESS, MEMBLOCK::size, and size.

vsnprintf()

int __cdecl vsnprintf	(	char *	buffer,
		size_t	count,
		const char *	format,
		va_list	argptr
	)

Definition at line 135 of file libc.cpp.

{   
    return vsprintf_s(buffer, count, format, argptr);
}

References count.

Variable Documentation

size

EXTERN_C __in size_t size

Definition at line 23 of file libc.h.