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#ifndef __KPATCH_SYSCALL_H_
#define __KPATCH_SYSCALL_H_
#include "kpatch-macros.h"
/*
* These kpatch-specific syscall definition macros can be used for patching a
* syscall.
*
* Attempting to patch a syscall typically results in an error, due to a
* missing fentry hook in the inner __do_sys##name() function. The fentry hook
* is missing because of the 'inline' annotation, which invokes 'notrace'.
*
* These macros are copied almost verbatim from the kernel, the main difference
* being a 'kpatch' prefix added to the __do_sys##name() function name. This
* causes kpatch-build to treat it as a new function (due to
* its new name), and its caller __se_sys##name() function is inlined by its own
* caller __x64_sys##name() function, which has an fentry hook. Since the
* kpatch versions do not provide SYSCALL_METADATA, specifically entries in the
* __syscalls_metadata and _ftrace_events sections, provide dummy values in
* these sections and instruct kpatch-build to ignore changes to them.
*
* To patch a syscall, just replace the use of the SYSCALL_DEFINE1 (or similar)
* macro with the "KPATCH_" prefixed version.
*/
#define KPATCH_SYSCALL_METADATA(sname) \
static struct syscall_metadata __used \
__section("__syscalls_metadata") \
*__p_syscall_meta_##sname = NULL; \
KPATCH_IGNORE_SECTION("__syscalls_metadata"); \
\
static struct trace_event_call __used \
__section("_ftrace_events") \
*__event_enter_##sname = NULL; \
KPATCH_IGNORE_SECTION("_ftrace_events")
#define KPATCH_SYSCALL_DEFINE1(name, ...) KPATCH_SYSCALL_DEFINEx(1, _##name, __VA_ARGS__)
#define KPATCH_SYSCALL_DEFINE2(name, ...) KPATCH_SYSCALL_DEFINEx(2, _##name, __VA_ARGS__)
#define KPATCH_SYSCALL_DEFINE3(name, ...) KPATCH_SYSCALL_DEFINEx(3, _##name, __VA_ARGS__)
#define KPATCH_SYSCALL_DEFINE4(name, ...) KPATCH_SYSCALL_DEFINEx(4, _##name, __VA_ARGS__)
#define KPATCH_SYSCALL_DEFINE5(name, ...) KPATCH_SYSCALL_DEFINEx(5, _##name, __VA_ARGS__)
#define KPATCH_SYSCALL_DEFINE6(name, ...) KPATCH_SYSCALL_DEFINEx(6, _##name, __VA_ARGS__)
#define KPATCH_SYSCALL_DEFINEx(x, sname, ...) \
KPATCH_SYSCALL_METADATA(sname); \
__KPATCH_SYSCALL_DEFINEx(x, sname, __VA_ARGS__)
#ifdef CONFIG_X86_64
/* arch/x86/include/asm/syscall_wrapper.h versions */
# if LINUX_VERSION_CODE >= KERNEL_VERSION(5, 7, 0)
# define __KPATCH_SYSCALL_DEFINEx(x, name, ...) \
static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
__X64_SYS_STUBx(x, name, __VA_ARGS__) \
__IA32_SYS_STUBx(x, name, __VA_ARGS__) \
static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \
{ \
long ret = __kpatch_do_sys##name(__MAP(x,__SC_CAST,__VA_ARGS__));\
__MAP(x,__SC_TEST,__VA_ARGS__); \
__PROTECT(x, ret,__MAP(x,__SC_ARGS,__VA_ARGS__)); \
return ret; \
} \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
# elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 17, 0)
# define __KPATCH_SYSCALL_DEFINEx(x, name, ...) \
asmlinkage long __x64_sys##name(const struct pt_regs *regs); \
ALLOW_ERROR_INJECTION(__x64_sys##name, ERRNO); \
static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
asmlinkage long __x64_sys##name(const struct pt_regs *regs) \
{ \
return __se_sys##name(SC_X86_64_REGS_TO_ARGS(x,__VA_ARGS__));\
} \
__IA32_SYS_STUBx(x, name, __VA_ARGS__) \
static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \
{ \
long ret = __kpatch_do_sys##name(__MAP(x,__SC_CAST,__VA_ARGS__));\
__MAP(x,__SC_TEST,__VA_ARGS__); \
__PROTECT(x, ret,__MAP(x,__SC_ARGS,__VA_ARGS__)); \
return ret; \
} \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
# endif /* LINUX_VERSION_CODE */
#elif defined(CONFIG_S390)
# if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 3, 0)
# define KPATCH_SYSCALL_WRAPPERS_V2
# else
# define KPATCH_SYSCALL_WRAPPERS_V1
# endif
# if defined(RHEL_RELEASE_CODE)
# if RHEL_RELEASE_CODE >= RHEL_RELEASE_VERSION(9, 6)
# define KPATCH_SYSCALL_WRAPPERS_V2
# else
# define KPATCH_SYSCALL_WRAPPERS_V1
# endif
# endif
/* arch/s390/include/asm/syscall_wrapper.h versions */
#if defined(KPATCH_SYSCALL_WRAPPERS_V1)
#if defined(CONFIG_COMPAT)
#define __KPATCH_S390_SYS_STUBx(x, name, ...) \
long __s390_sys##name(struct pt_regs *regs); \
ALLOW_ERROR_INJECTION(__s390_sys##name, ERRNO); \
long __s390_sys##name(struct pt_regs *regs) \
{ \
long ret = __kpatch_do_sys##name(SYSCALL_PT_ARGS(x, regs, \
__SC_COMPAT_CAST, __MAP(x, __SC_TYPE, __VA_ARGS__))); \
__MAP(x,__SC_TEST,__VA_ARGS__); \
return ret; \
}
#else
#define __KPATCH_S390_SYS_STUBx(x, name, ...)
#endif /* CONFIG_COMPAT */
#define __KPATCH_SYSCALL_DEFINEx(x, name, ...) \
__diag_push(); \
__diag_ignore(GCC, 8, "-Wattribute-alias", \
"Type aliasing is used to sanitize syscall arguments"); \
long __s390x_sys##name(struct pt_regs *regs) \
__attribute__((alias(__stringify(__se_sys##name)))); \
ALLOW_ERROR_INJECTION(__s390x_sys##name, ERRNO); \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)); \
long __se_sys##name(struct pt_regs *regs); \
__KPATCH_S390_SYS_STUBx(x, name, __VA_ARGS__) \
long __se_sys##name(struct pt_regs *regs) \
{ \
long ret = __kpatch_do_sys##name(SYSCALL_PT_ARGS(x, regs, \
__SC_CAST, __MAP(x, __SC_TYPE, __VA_ARGS__))); \
__MAP(x,__SC_TEST,__VA_ARGS__); \
return ret; \
} \
__diag_pop(); \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
# else /* KPATCH_SYSCALL_WRAPPERS_V2 */
#if defined(CONFIG_COMPAT)
#define __KPATCH_S390_SYS_STUBx(x, name, ...) \
long __s390_sys##name(struct pt_regs *regs); \
ALLOW_ERROR_INJECTION(__s390_sys##name, ERRNO); \
static inline long ___se_sys##name(__MAP(x, __SC_LONG, __VA_ARGS__)); \
long __s390_sys##name(struct pt_regs *regs) \
{ \
return ___se_sys##name(SC_S390_REGS_TO_ARGS(x, __VA_ARGS__)); \
} \
static inline long ___se_sys##name(__MAP(x, __SC_LONG, __VA_ARGS__)) \
{ \
__MAP(x, __SC_TEST, __VA_ARGS__); \
return __kpatch_do_sys##name(__MAP(x, __SC_COMPAT_CAST, __VA_ARGS__)); \
}
#else
#define __KPATCH_S390_SYS_STUBx(x, name, ...)
#endif /* CONFIG_COMPAT */
#define __KPATCH_SYSCALL_DEFINEx(x, name, ...) \
long __s390x_sys##name(struct pt_regs *regs); \
ALLOW_ERROR_INJECTION(__s390x_sys##name, ERRNO); \
static inline long __se_sys##name(__MAP(x, __SC_LONG, __VA_ARGS__)); \
static inline long __kpatch_do_sys##name(__MAP(x, __SC_DECL, __VA_ARGS__)); \
__KPATCH_S390_SYS_STUBx(x, name, __VA_ARGS__); \
long __s390x_sys##name(struct pt_regs *regs) \
{ \
return __se_sys##name(SC_S390_REGS_TO_ARGS(x, __VA_ARGS__)); \
} \
static inline long __se_sys##name(__MAP(x, __SC_LONG, __VA_ARGS__)) \
{ \
__MAP(x, __SC_TEST, __VA_ARGS__); \
return __kpatch_do_sys##name(__MAP(x, __SC_CAST, __VA_ARGS__)); \
} \
static inline long __kpatch_do_sys##name(__MAP(x, __SC_DECL, __VA_ARGS__))
#endif /* KPATCH_SYSCALL_WRAPPERS_V2 */
#elif defined(CONFIG_PPC64)
/* arch/powerpc/include/asm/syscall_wrapper.h versions */
# if LINUX_VERSION_CODE >= KERNEL_VERSION(6, 1, 0)
# define __KPATCH_SYSCALL_DEFINEx(x, name, ...) \
long sys##name(const struct pt_regs *regs); \
ALLOW_ERROR_INJECTION(sys##name, ERRNO); \
static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
__attribute__((optimize("-fno-optimize-sibling-calls"))) \
long sys##name(const struct pt_regs *regs) \
{ \
return __se_sys##name(SC_POWERPC_REGS_TO_ARGS(x,__VA_ARGS__)); \
} \
static long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \
{ \
long ret = __kpatch_do_sys##name(__MAP(x,__SC_CAST,__VA_ARGS__));\
__MAP(x,__SC_TEST,__VA_ARGS__); \
__PROTECT(x, ret,__MAP(x,__SC_ARGS,__VA_ARGS__)); \
return ret; \
} \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
# endif /* LINUX_VERSION_CODE */
#endif /* CONFIG_X86_64 */
#ifndef __KPATCH_SYSCALL_DEFINEx
/* include/linux/syscalls.h versions */
# if LINUX_VERSION_CODE >= KERNEL_VERSION(4, 18, 0)
# define __KPATCH_SYSCALL_DEFINEx(x, name, ...) \
__diag_push(); \
__diag_ignore(GCC, 8, "-Wattribute-alias", \
"Type aliasing is used to sanitize syscall arguments");\
asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) \
__attribute__((alias(__stringify(__se_sys##name)))); \
ALLOW_ERROR_INJECTION(sys##name, ERRNO); \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
asmlinkage long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
asmlinkage long __attribute__((optimize("-fno-optimize-sibling-calls")))\
__se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \
{ \
long ret = __kpatch_do_sys##name(__MAP(x,__SC_CAST,__VA_ARGS__));\
__MAP(x,__SC_TEST,__VA_ARGS__); \
__PROTECT(x, ret,__MAP(x,__SC_ARGS,__VA_ARGS__)); \
return ret; \
} \
__diag_pop(); \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
# elif LINUX_VERSION_CODE >= KERNEL_VERSION(4, 17, 0)
# define __KPATCH_SYSCALL_DEFINEx(x, name, ...) \
asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) \
__attribute__((alias(__stringify(__se_sys##name)))); \
ALLOW_ERROR_INJECTION(sys##name, ERRNO); \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__));\
asmlinkage long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
asmlinkage long __se_sys##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \
{ \
long ret = __kpatch_do_sys##name(__MAP(x,__SC_CAST,__VA_ARGS__));\
__MAP(x,__SC_TEST,__VA_ARGS__); \
__PROTECT(x, ret,__MAP(x,__SC_ARGS,__VA_ARGS__)); \
return ret; \
} \
static inline long __kpatch_do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__))
# else
# define __KPATCH_SYSCALL_DEFINEx(x, name, ...) \
asmlinkage long sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) \
__attribute__((alias(__stringify(SyS##name)))); \
static inline long __kpatch_SYSC##name(__MAP(x,__SC_DECL,__VA_ARGS__)); \
asmlinkage long SyS##name(__MAP(x,__SC_LONG,__VA_ARGS__)); \
asmlinkage long SyS##name(__MAP(x,__SC_LONG,__VA_ARGS__)) \
{ \
long ret = __kpatch_SYSC##name(__MAP(x,__SC_CAST,__VA_ARGS__)); \
__MAP(x,__SC_TEST,__VA_ARGS__); \
__PROTECT(x, ret,__MAP(x,__SC_ARGS,__VA_ARGS__)); \
return ret; \
} \
static inline long __kpatch_SYSC##name(__MAP(x,__SC_DECL,__VA_ARGS__))
# endif
#endif /* __KPATCH_SYSCALL_DEFINEx */
#endif /* __KPATCH_SYSCALL_H_ */
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