zephyr/kernel/userspace_handler.c

68 lines
1.7 KiB
C
Raw Normal View History

/*
* Copyright (c) 2017 Intel Corporation
*
* SPDX-License-Identifier: Apache-2.0
*/
#include <kernel.h>
#include <syscall_handler.h>
#include <kernel_structs.h>
static struct z_object *validate_any_object(const void *obj)
{
struct z_object *ko;
int ret;
ko = z_object_find(obj);
/* This can be any kernel object and it doesn't have to be
* initialized
*/
ret = z_object_validate(ko, K_OBJ_ANY, _OBJ_INIT_ANY);
if (ret != 0) {
#ifdef CONFIG_LOG
z_dump_object_error(ret, obj, ko, K_OBJ_ANY);
#endif
return NULL;
}
return ko;
}
/* Normally these would be included in userspace.c, but the way
* syscall_dispatch.c declares weak handlers results in build errors if these
* are located in userspace.c. Just put in a separate file.
*
* To avoid double z_object_find() lookups, we don't call the implementation
* function, but call a level deeper.
*/
static inline void z_vrfy_k_object_access_grant(const void *object,
struct k_thread *thread)
{
struct z_object *ko;
Z_OOPS(Z_SYSCALL_OBJ_INIT(thread, K_OBJ_THREAD));
userspace: Support for split 64 bit arguments System call arguments, at the arch layer, are single words. So passing wider values requires splitting them into two registers at call time. This gets even more complicated for values (e.g k_timeout_t) that may have different sizes depending on configuration. This patch adds a feature to gen_syscalls.py to detect functions with wide arguments and automatically generates code to split/unsplit them. Unfortunately the current scheme of Z_SYSCALL_DECLARE_* macros won't work with functions like this, because for N arguments (our current maximum N is 10) there are 2^N possible configurations of argument widths. So this generates the complete functions for each handler and wrapper, effectively doing in python what was originally done in the preprocessor. Another complexity is that traditional the z_hdlr_*() function for a system call has taken the raw list of word arguments, which does not work when some of those arguments must be 64 bit types. So instead of using a single Z_SYSCALL_HANDLER macro, this splits the job of z_hdlr_*() into two steps: An automatically-generated unmarshalling function, z_mrsh_*(), which then calls a user-supplied verification function z_vrfy_*(). The verification function is typesafe, and is a simple C function with exactly the same argument and return signature as the syscall impl function. It is also not responsible for validating the pointers to the extra parameter array or a wide return value, that code gets automatically generated. This commit includes new vrfy/msrh handling for all syscalls invoked during CI runs. Future commits will port the less testable code. Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2019-08-07 04:34:31 +08:00
ko = validate_any_object(object);
Z_OOPS(Z_SYSCALL_VERIFY_MSG(ko != NULL, "object %p access denied",
userspace: Support for split 64 bit arguments System call arguments, at the arch layer, are single words. So passing wider values requires splitting them into two registers at call time. This gets even more complicated for values (e.g k_timeout_t) that may have different sizes depending on configuration. This patch adds a feature to gen_syscalls.py to detect functions with wide arguments and automatically generates code to split/unsplit them. Unfortunately the current scheme of Z_SYSCALL_DECLARE_* macros won't work with functions like this, because for N arguments (our current maximum N is 10) there are 2^N possible configurations of argument widths. So this generates the complete functions for each handler and wrapper, effectively doing in python what was originally done in the preprocessor. Another complexity is that traditional the z_hdlr_*() function for a system call has taken the raw list of word arguments, which does not work when some of those arguments must be 64 bit types. So instead of using a single Z_SYSCALL_HANDLER macro, this splits the job of z_hdlr_*() into two steps: An automatically-generated unmarshalling function, z_mrsh_*(), which then calls a user-supplied verification function z_vrfy_*(). The verification function is typesafe, and is a simple C function with exactly the same argument and return signature as the syscall impl function. It is also not responsible for validating the pointers to the extra parameter array or a wide return value, that code gets automatically generated. This commit includes new vrfy/msrh handling for all syscalls invoked during CI runs. Future commits will port the less testable code. Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2019-08-07 04:34:31 +08:00
object));
z_thread_perms_set(ko, thread);
}
userspace: Support for split 64 bit arguments System call arguments, at the arch layer, are single words. So passing wider values requires splitting them into two registers at call time. This gets even more complicated for values (e.g k_timeout_t) that may have different sizes depending on configuration. This patch adds a feature to gen_syscalls.py to detect functions with wide arguments and automatically generates code to split/unsplit them. Unfortunately the current scheme of Z_SYSCALL_DECLARE_* macros won't work with functions like this, because for N arguments (our current maximum N is 10) there are 2^N possible configurations of argument widths. So this generates the complete functions for each handler and wrapper, effectively doing in python what was originally done in the preprocessor. Another complexity is that traditional the z_hdlr_*() function for a system call has taken the raw list of word arguments, which does not work when some of those arguments must be 64 bit types. So instead of using a single Z_SYSCALL_HANDLER macro, this splits the job of z_hdlr_*() into two steps: An automatically-generated unmarshalling function, z_mrsh_*(), which then calls a user-supplied verification function z_vrfy_*(). The verification function is typesafe, and is a simple C function with exactly the same argument and return signature as the syscall impl function. It is also not responsible for validating the pointers to the extra parameter array or a wide return value, that code gets automatically generated. This commit includes new vrfy/msrh handling for all syscalls invoked during CI runs. Future commits will port the less testable code. Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2019-08-07 04:34:31 +08:00
#include <syscalls/k_object_access_grant_mrsh.c>
static inline void z_vrfy_k_object_release(const void *object)
{
struct z_object *ko;
ko = validate_any_object((void *)object);
Z_OOPS(Z_SYSCALL_VERIFY_MSG(ko != NULL, "object %p access denied",
(void *)object));
z_thread_perms_clear(ko, _current);
}
userspace: Support for split 64 bit arguments System call arguments, at the arch layer, are single words. So passing wider values requires splitting them into two registers at call time. This gets even more complicated for values (e.g k_timeout_t) that may have different sizes depending on configuration. This patch adds a feature to gen_syscalls.py to detect functions with wide arguments and automatically generates code to split/unsplit them. Unfortunately the current scheme of Z_SYSCALL_DECLARE_* macros won't work with functions like this, because for N arguments (our current maximum N is 10) there are 2^N possible configurations of argument widths. So this generates the complete functions for each handler and wrapper, effectively doing in python what was originally done in the preprocessor. Another complexity is that traditional the z_hdlr_*() function for a system call has taken the raw list of word arguments, which does not work when some of those arguments must be 64 bit types. So instead of using a single Z_SYSCALL_HANDLER macro, this splits the job of z_hdlr_*() into two steps: An automatically-generated unmarshalling function, z_mrsh_*(), which then calls a user-supplied verification function z_vrfy_*(). The verification function is typesafe, and is a simple C function with exactly the same argument and return signature as the syscall impl function. It is also not responsible for validating the pointers to the extra parameter array or a wide return value, that code gets automatically generated. This commit includes new vrfy/msrh handling for all syscalls invoked during CI runs. Future commits will port the less testable code. Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2019-08-07 04:34:31 +08:00
#include <syscalls/k_object_release_mrsh.c>
userspace: Support for split 64 bit arguments System call arguments, at the arch layer, are single words. So passing wider values requires splitting them into two registers at call time. This gets even more complicated for values (e.g k_timeout_t) that may have different sizes depending on configuration. This patch adds a feature to gen_syscalls.py to detect functions with wide arguments and automatically generates code to split/unsplit them. Unfortunately the current scheme of Z_SYSCALL_DECLARE_* macros won't work with functions like this, because for N arguments (our current maximum N is 10) there are 2^N possible configurations of argument widths. So this generates the complete functions for each handler and wrapper, effectively doing in python what was originally done in the preprocessor. Another complexity is that traditional the z_hdlr_*() function for a system call has taken the raw list of word arguments, which does not work when some of those arguments must be 64 bit types. So instead of using a single Z_SYSCALL_HANDLER macro, this splits the job of z_hdlr_*() into two steps: An automatically-generated unmarshalling function, z_mrsh_*(), which then calls a user-supplied verification function z_vrfy_*(). The verification function is typesafe, and is a simple C function with exactly the same argument and return signature as the syscall impl function. It is also not responsible for validating the pointers to the extra parameter array or a wide return value, that code gets automatically generated. This commit includes new vrfy/msrh handling for all syscalls invoked during CI runs. Future commits will port the less testable code. Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2019-08-07 04:34:31 +08:00
static inline void *z_vrfy_k_object_alloc(enum k_objects otype)
{
userspace: Support for split 64 bit arguments System call arguments, at the arch layer, are single words. So passing wider values requires splitting them into two registers at call time. This gets even more complicated for values (e.g k_timeout_t) that may have different sizes depending on configuration. This patch adds a feature to gen_syscalls.py to detect functions with wide arguments and automatically generates code to split/unsplit them. Unfortunately the current scheme of Z_SYSCALL_DECLARE_* macros won't work with functions like this, because for N arguments (our current maximum N is 10) there are 2^N possible configurations of argument widths. So this generates the complete functions for each handler and wrapper, effectively doing in python what was originally done in the preprocessor. Another complexity is that traditional the z_hdlr_*() function for a system call has taken the raw list of word arguments, which does not work when some of those arguments must be 64 bit types. So instead of using a single Z_SYSCALL_HANDLER macro, this splits the job of z_hdlr_*() into two steps: An automatically-generated unmarshalling function, z_mrsh_*(), which then calls a user-supplied verification function z_vrfy_*(). The verification function is typesafe, and is a simple C function with exactly the same argument and return signature as the syscall impl function. It is also not responsible for validating the pointers to the extra parameter array or a wide return value, that code gets automatically generated. This commit includes new vrfy/msrh handling for all syscalls invoked during CI runs. Future commits will port the less testable code. Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2019-08-07 04:34:31 +08:00
return z_impl_k_object_alloc(otype);
}
userspace: Support for split 64 bit arguments System call arguments, at the arch layer, are single words. So passing wider values requires splitting them into two registers at call time. This gets even more complicated for values (e.g k_timeout_t) that may have different sizes depending on configuration. This patch adds a feature to gen_syscalls.py to detect functions with wide arguments and automatically generates code to split/unsplit them. Unfortunately the current scheme of Z_SYSCALL_DECLARE_* macros won't work with functions like this, because for N arguments (our current maximum N is 10) there are 2^N possible configurations of argument widths. So this generates the complete functions for each handler and wrapper, effectively doing in python what was originally done in the preprocessor. Another complexity is that traditional the z_hdlr_*() function for a system call has taken the raw list of word arguments, which does not work when some of those arguments must be 64 bit types. So instead of using a single Z_SYSCALL_HANDLER macro, this splits the job of z_hdlr_*() into two steps: An automatically-generated unmarshalling function, z_mrsh_*(), which then calls a user-supplied verification function z_vrfy_*(). The verification function is typesafe, and is a simple C function with exactly the same argument and return signature as the syscall impl function. It is also not responsible for validating the pointers to the extra parameter array or a wide return value, that code gets automatically generated. This commit includes new vrfy/msrh handling for all syscalls invoked during CI runs. Future commits will port the less testable code. Signed-off-by: Andy Ross <andrew.j.ross@intel.com>
2019-08-07 04:34:31 +08:00
#include <syscalls/k_object_alloc_mrsh.c>