diff options
Diffstat (limited to 'arch/x86/kernel/signal_64.c')
| -rw-r--r-- | arch/x86/kernel/signal_64.c | 30 |
1 files changed, 22 insertions, 8 deletions
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c index 827179c..ccb2a45 100644 --- a/arch/x86/kernel/signal_64.c +++ b/arch/x86/kernel/signal_64.c @@ -285,14 +285,6 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, even if the handler happens to be interrupting 32-bit code. */ regs->cs = __USER_CS; - /* This, by contrast, has nothing to do with segment registers - - see include/asm-x86_64/uaccess.h for details. */ - set_fs(USER_DS); - - regs->flags &= ~(X86_EFLAGS_TF | X86_EFLAGS_DF); - if (test_thread_flag(TIF_SINGLESTEP)) - ptrace_notify(SIGTRAP); - return 0; give_sigsegv: @@ -380,6 +372,28 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka, ret = setup_rt_frame(sig, ka, info, oldset, regs); if (ret == 0) { + /* + * This has nothing to do with segment registers, + * despite the name. This magic affects uaccess.h + * macros' behavior. Reset it to the normal setting. + */ + set_fs(USER_DS); + + /* + * Clear the direction flag as per the ABI for function entry. + */ + regs->flags &= ~X86_EFLAGS_DF; + + /* + * Clear TF when entering the signal handler, but + * notify any tracer that was single-stepping it. + * The tracer may want to single-step inside the + * handler too. + */ + regs->flags &= ~X86_EFLAGS_TF; + if (test_thread_flag(TIF_SINGLESTEP)) + ptrace_notify(SIGTRAP); + spin_lock_irq(¤t->sighand->siglock); sigorsets(¤t->blocked,¤t->blocked,&ka->sa.sa_mask); if (!(ka->sa.sa_flags & SA_NODEFER)) |