uprobe: Wire up uretprobe system call

Wiring up uretprobe system call, which comes in following changes.
We need to do the wiring before, because the uretprobe implementation
needs the syscall number.

Note at the moment uretprobe syscall is supported only for native
64-bit process.

Link: https://lore.kernel.org/all/[email protected]/

Reviewed-by: Oleg Nesterov <[email protected]>
Reviewed-by: Masami Hiramatsu (Google) <[email protected]>
Acked-by: Andrii Nakryiko <[email protected]>
Signed-off-by: Jiri Olsa <[email protected]>
Signed-off-by: Masami Hiramatsu (Google) <[email protected]>

Author: olsajiri

arch/x86/entry/syscalls/syscall_64.tbl

@@ -384,6 +384,7 @@
 460	common	lsm_set_self_attr	sys_lsm_set_self_attr
 461	common	lsm_list_modules	sys_lsm_list_modules
 462 	common  mseal			sys_mseal
+463	64	uretprobe		sys_uretprobe
 
 #
 # Due to a historical design error, certain syscalls are numbered differently

include/linux/syscalls.h

@@ -973,6 +973,8 @@ asmlinkage long sys_lsm_list_modules(u64 *ids, u32 *size, u32 flags);
 /* x86 */
 asmlinkage long sys_ioperm(unsigned long from, unsigned long num, int on);
 
+asmlinkage long sys_uretprobe(void);
+
 /* pciconfig: alpha, arm, arm64, ia64, sparc */
 asmlinkage long sys_pciconfig_read(unsigned long bus, unsigned long dfn,
 				unsigned long off, unsigned long len,

include/uapi/asm-generic/unistd.h

@@ -845,8 +845,11 @@ __SYSCALL(__NR_lsm_list_modules, sys_lsm_list_modules)
 #define __NR_mseal 462
 __SYSCALL(__NR_mseal, sys_mseal)
 
+#define __NR_uretprobe 463
+__SYSCALL(__NR_uretprobe, sys_uretprobe)
+
 #undef __NR_syscalls
-#define __NR_syscalls 463
+#define __NR_syscalls 464
 
 /*
  * 32 bit systems traditionally used different

kernel/sys_ni.c

@@ -392,3 +392,5 @@ COND_SYSCALL(setuid16);
 
 /* restartable sequence */
 COND_SYSCALL(rseq);
+
+COND_SYSCALL(uretprobe);