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 <ruanjinjie@huawei.com> --- 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