diff options
Diffstat (limited to 'arch/powerpc/kernel/ptrace.c')
| -rw-r--r-- | arch/powerpc/kernel/ptrace.c | 49 |
1 files changed, 31 insertions, 18 deletions
diff --git a/arch/powerpc/kernel/ptrace.c b/arch/powerpc/kernel/ptrace.c index afb819f4ca68..cdd5d1d3ae41 100644 --- a/arch/powerpc/kernel/ptrace.c +++ b/arch/powerpc/kernel/ptrace.c @@ -3263,27 +3263,40 @@ static inline int do_seccomp(struct pt_regs *regs) { return 0; } */ long do_syscall_trace_enter(struct pt_regs *regs) { + u32 flags; + user_exit(); - if (test_thread_flag(TIF_SYSCALL_EMU)) { - ptrace_report_syscall(regs); - /* - * Returning -1 will skip the syscall execution. We want to - * avoid clobbering any register also, thus, not 'gotoing' - * skip label. - */ - return -1; - } + flags = READ_ONCE(current_thread_info()->flags) & + (_TIF_SYSCALL_EMU | _TIF_SYSCALL_TRACE); - /* - * The tracer may decide to abort the syscall, if so tracehook - * will return !0. Note that the tracer may also just change - * regs->gpr[0] to an invalid syscall number, that is handled - * below on the exit path. - */ - if (test_thread_flag(TIF_SYSCALL_TRACE) && - tracehook_report_syscall_entry(regs)) - goto skip; + if (flags) { + int rc = tracehook_report_syscall_entry(regs); + + if (unlikely(flags & _TIF_SYSCALL_EMU)) { + /* + * A nonzero return code from + * tracehook_report_syscall_entry() tells us to prevent + * the syscall execution, but we are not going to + * execute it anyway. + * + * Returning -1 will skip the syscall execution. We want + * to avoid clobbering any registers, so we don't goto + * the skip label below. + */ + return -1; + } + + if (rc) { + /* + * The tracer decided to abort the syscall. Note that + * the tracer may also just change regs->gpr[0] to an + * invalid syscall number, that is handled below on the + * exit path. + */ + goto skip; + } + } /* Run seccomp after ptrace; allow it to set gpr[3]. */ if (do_seccomp(regs)) |