strncpy_from_unsafe

函数名称：strncpy_from_unsafe_user: - Copy a NUL terminated string from unsafe user* address.*@dst: Destination address, in kernel space. This buffer must be at* least @count bytes long.*@unsafe_addr: Unsafe user address.

函数原型：long strncpy_from_unsafe_user(char *dst, const void __user *unsafe_addr, long count)

返回类型：long

参数：

类型	参数	名称
char *	dst
const void __user *	unsafe_addr
long	count

228

old_fs等于获取当前进程地址空间上限()

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如果此条件成立可能性小(为编译器优化)(count <= 0)则返回:0

234

设置寄存器值(fs)

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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.

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ret等于复制用户字符串

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pagefault_enable()

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设置寄存器值(fs)

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如果ret大于等于count则

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ret等于count

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dst[ret - 1]等于'\0'

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否则如果ret大于0则

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ret自加

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返回:ret

**调用者**
名称	描述
fetch_store_string_user	Fetch a null-terminated string from user. Caller MUST set (u32 )buf* with max length and relative data location.
____bpf_probe_read_user_str

源代码转换工具开放的插件接口	X
支持：c/c++/esqlc/java Oracle/Informix/Mysql 插件可实现：逻辑报告代码生成和批量转换代码

函数逻辑报告