As syscall_exit_work() do not handle seccomp, so not check _TIF_SECCOMP
for syscall_exit_work().

And as the man manual of PTRACE_SYSEMU and PTRACE_SYSEMU_SINGLESTEP
said, "For PTRACE_SYSEMU, continue and stop on entry to the next system
call, which will not be executed. For PTRACE_SYSEMU_SINGLESTEP, do the same
but also singlestep if not a system call.". So only the syscall entry need
to be reported for SYSCALL_EMU, so not check _TIF_SYSCALL_EMU for
syscall_exit_work().

After this, audit_syscall_exit() and report_syscall_exit() will
no longer be called if only SECCOMP and/or SYSCALL_EMU is set.

And remove has_syscall_work() by the way as currently it is only used in
el0_svc_common().

This is another preparation for moving arm64 over to the generic
entry code.

Link:https://man7.org/linux/man-pages/man2/ptrace.2.html
Signed-off-by: Jinjie Ruan <[email protected]>
---
 arch/arm64/include/asm/syscall.h     | 5 -----
 arch/arm64/include/asm/thread_info.h | 3 +++
 arch/arm64/kernel/ptrace.c           | 2 +-
 arch/arm64/kernel/syscall.c          | 2 +-
 4 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/arch/arm64/include/asm/syscall.h b/arch/arm64/include/asm/syscall.h
index ccdaa805aa52..9f2aa9c57560 100644
--- a/arch/arm64/include/asm/syscall.h
+++ b/arch/arm64/include/asm/syscall.h
@@ -120,11 +120,6 @@ static inline int syscall_get_arch(struct task_struct 
*task)
        return AUDIT_ARCH_AARCH64;
 }
 
-static inline bool has_syscall_work(unsigned long flags)
-{
-       return unlikely(flags & _TIF_SYSCALL_WORK);
-}
-
 int syscall_trace_enter(struct pt_regs *regs, long syscall, unsigned long 
flags);
 void syscall_exit_to_user_mode_prepare(struct pt_regs *regs);
 
diff --git a/arch/arm64/include/asm/thread_info.h 
b/arch/arm64/include/asm/thread_info.h
index ff4998fa1844..8d308ef64612 100644
--- a/arch/arm64/include/asm/thread_info.h
+++ b/arch/arm64/include/asm/thread_info.h
@@ -110,6 +110,9 @@ void arch_setup_new_exec(void);
                                 _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \
                                 _TIF_SYSCALL_EMU)
 
+#define _TIF_SYSCALL_EXIT_WORK (_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
+                                _TIF_SYSCALL_TRACEPOINT)
+
 #ifdef CONFIG_SHADOW_CALL_STACK
 #define INIT_SCS                                                       \
        .scs_base       = init_shadow_call_stack,                       \
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
index 25fdf320d73a..3e233968efa2 100644
--- a/arch/arm64/kernel/ptrace.c
+++ b/arch/arm64/kernel/ptrace.c
@@ -2431,7 +2431,7 @@ void syscall_exit_to_user_mode_prepare(struct pt_regs 
*regs)
 
        rseq_syscall(regs);
 
-       if (has_syscall_work(flags) || flags & _TIF_SINGLESTEP)
+       if (unlikely(flags & _TIF_SYSCALL_EXIT_WORK) || flags & _TIF_SINGLESTEP)
                syscall_exit_work(regs, flags);
 }
 
diff --git a/arch/arm64/kernel/syscall.c b/arch/arm64/kernel/syscall.c
index 65021d0f49e1..881fd261e8cb 100644
--- a/arch/arm64/kernel/syscall.c
+++ b/arch/arm64/kernel/syscall.c
@@ -101,7 +101,7 @@ static void el0_svc_common(struct pt_regs *regs, int scno, 
int sc_nr,
                return;
        }
 
-       if (has_syscall_work(flags)) {
+       if (unlikely(flags & _TIF_SYSCALL_WORK)) {
                /*
                 * The de-facto standard way to skip a system call using ptrace
                 * is to set the system call to -1 (NO_SYSCALL) and set x0 to a
-- 
2.34.1


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