strndup_user

函数名称：strndup_user - duplicate an existing string from user space*@s: The string to duplicate*@n: Maximum number of bytes to copy, including the trailing NUL.* Return: newly allocated copy of @s or an ERR_PTR() in case of error

函数原型：char *strndup_user(const char __user *s, long n)

返回类型：char

参数：

类型	参数	名称
const char __user *	s
long	n

**调用者**
名称	描述
perf_event_set_filter
SYSCALL_DEFINE4	Search the process keyrings and keyring trees linked from those for a* matching key. Keyrings must have appropriate Search permission to be* searched.* If a key is found, it will be attached to the destination keyring if there's
keyctl_join_session_keyring	Join a (named) session keyring.* Create and join an anonymous session keyring or join a named session* keyring, creating it if necessary. A named session keyring must have Search* permission for it to be joined. Session keyrings without this permit will
keyctl_keyring_search	Search the specified keyring and any keyrings it links to for a matching* key
keyctl_restrict_keyring	Apply a restriction to a given keyring.* The caller must have Setattr permission to change keyring restrictions.* The requested type name may be a NULL pointer to reject all attempts* to link to the keyring. In this case, _restriction must also be NULL.
__keyctl_dh_compute
keyctl_pkey_params_get	Interpret parameters. Callers must always call the free function* on params, even if an error is returned.
SYSCALL_DEFINE2	Open a filesystem by name so that it can be configured for mounting.* We are allowed to specify a container in which the filesystem will be* opened, thereby indicating which namespaces will be used (notably, which
load_module	Allocate and load the module: note that size of section 0 is alwayszero, and we rely on this for optional sections.
SYSCALL_DEFINE5	Extract the description of a new key from userspace and either add it as a* new key to the specified keyring or update a matching key in that keyring.* If the description is NULL or an empty string, the key type is asked to* generate one from the payload.
copy_mount_string

函数逻辑报告