diff options
Diffstat (limited to 'arch/arm/kernel/signal.c')
| -rw-r--r-- | arch/arm/kernel/signal.c | 95 |
1 files changed, 48 insertions, 47 deletions
diff --git a/arch/arm/kernel/signal.c b/arch/arm/kernel/signal.c index 17fc36c41cff..536c5d6b340b 100644 --- a/arch/arm/kernel/signal.c +++ b/arch/arm/kernel/signal.c @@ -22,13 +22,12 @@ #include "signal.h" -#define _BLOCKABLE (~(sigmask(SIGKILL) | sigmask(SIGSTOP))) - /* * For ARM syscalls, we encode the syscall number into the instruction. */ #define SWI_SYS_SIGRETURN (0xef000000|(__NR_sigreturn)|(__NR_OABI_SYSCALL_BASE)) #define SWI_SYS_RT_SIGRETURN (0xef000000|(__NR_rt_sigreturn)|(__NR_OABI_SYSCALL_BASE)) +#define SWI_SYS_RESTART (0xef000000|__NR_restart_syscall|__NR_OABI_SYSCALL_BASE) /* * With EABI, the syscall number has to be loaded into r7. @@ -49,6 +48,18 @@ const unsigned long sigreturn_codes[7] = { }; /* + * Either we support OABI only, or we have EABI with the OABI + * compat layer enabled. In the later case we don't know if + * user space is EABI or not, and if not we must not clobber r7. + * Always using the OABI syscall solves that issue and works for + * all those cases. + */ +const unsigned long syscall_restart_code[2] = { + SWI_SYS_RESTART, /* swi __NR_restart_syscall */ + 0xe49df004, /* ldr pc, [sp], #4 */ +}; + +/* * atomically swap in the new signal mask, and wait for a signal. */ asmlinkage int sys_sigsuspend(int restart, unsigned long oldmask, old_sigset_t mask) @@ -210,10 +221,8 @@ static int restore_sigframe(struct pt_regs *regs, struct sigframe __user *sf) int err; err = __copy_from_user(&set, &sf->uc.uc_sigmask, sizeof(set)); - if (err == 0) { - sigdelsetmask(&set, ~_BLOCKABLE); + if (err == 0) set_current_blocked(&set); - } __get_user_error(regs->ARM_r0, &sf->uc.uc_mcontext.arm_r0, err); __get_user_error(regs->ARM_r1, &sf->uc.uc_mcontext.arm_r1, err); @@ -528,13 +537,13 @@ setup_rt_frame(int usig, struct k_sigaction *ka, siginfo_t *info, /* * OK, we're invoking a handler */ -static int +static void handle_signal(unsigned long sig, struct k_sigaction *ka, - siginfo_t *info, sigset_t *oldset, - struct pt_regs * regs) + siginfo_t *info, struct pt_regs *regs) { struct thread_info *thread = current_thread_info(); struct task_struct *tsk = current; + sigset_t *oldset = sigmask_to_save(); int usig = sig; int ret; @@ -559,17 +568,9 @@ handle_signal(unsigned long sig, struct k_sigaction *ka, if (ret != 0) { force_sigsegv(sig, tsk); - return ret; + return; } - - /* - * Block the signal if we were successful. - */ - block_sigmask(ka, sig); - - tracehook_signal_handler(sig, info, ka, regs, 0); - - return 0; + signal_delivered(sig, info, ka, regs, 0); } /* @@ -604,10 +605,12 @@ static void do_signal(struct pt_regs *regs, int syscall) case -ERESTARTNOHAND: case -ERESTARTSYS: case -ERESTARTNOINTR: - case -ERESTART_RESTARTBLOCK: regs->ARM_r0 = regs->ARM_ORIG_r0; regs->ARM_pc = restart_addr; break; + case -ERESTART_RESTARTBLOCK: + regs->ARM_r0 = -EINTR; + break; } } @@ -617,38 +620,21 @@ static void do_signal(struct pt_regs *regs, int syscall) */ signr = get_signal_to_deliver(&info, &ka, regs, NULL); if (signr > 0) { - sigset_t *oldset; - /* * Depending on the signal settings we may need to revert the * decision to restart the system call. But skip this if a * debugger has chosen to restart at a different PC. */ if (regs->ARM_pc == restart_addr) { - if (retval == -ERESTARTNOHAND || - retval == -ERESTART_RESTARTBLOCK + if (retval == -ERESTARTNOHAND || (retval == -ERESTARTSYS && !(ka.sa.sa_flags & SA_RESTART))) { regs->ARM_r0 = -EINTR; regs->ARM_pc = continue_addr; } - clear_thread_flag(TIF_SYSCALL_RESTARTSYS); } - if (test_thread_flag(TIF_RESTORE_SIGMASK)) - oldset = ¤t->saved_sigmask; - else - oldset = ¤t->blocked; - if (handle_signal(signr, &ka, &info, oldset, regs) == 0) { - /* - * A signal was successfully delivered; the saved - * sigmask will have been stored in the signal frame, - * and will be restored by sigreturn, so we can simply - * clear the TIF_RESTORE_SIGMASK flag. - */ - if (test_thread_flag(TIF_RESTORE_SIGMASK)) - clear_thread_flag(TIF_RESTORE_SIGMASK); - } + handle_signal(signr, &ka, &info, regs); return; } @@ -659,15 +645,32 @@ static void do_signal(struct pt_regs *regs, int syscall) * ignore the restart. */ if (retval == -ERESTART_RESTARTBLOCK - && regs->ARM_pc == restart_addr) - set_thread_flag(TIF_SYSCALL_RESTARTSYS); + && regs->ARM_pc == continue_addr) { + if (thumb_mode(regs)) { + regs->ARM_r7 = __NR_restart_syscall - __NR_SYSCALL_BASE; + regs->ARM_pc -= 2; + } else { +#if defined(CONFIG_AEABI) && !defined(CONFIG_OABI_COMPAT) + regs->ARM_r7 = __NR_restart_syscall; + regs->ARM_pc -= 4; +#else + u32 __user *usp; + + regs->ARM_sp -= 4; + usp = (u32 __user *)regs->ARM_sp; + + if (put_user(regs->ARM_pc, usp) == 0) { + regs->ARM_pc = KERN_RESTART_CODE; + } else { + regs->ARM_sp += 4; + force_sigsegv(0, current); + } +#endif + } + } } - /* If there's no signal to deliver, we just put the saved sigmask - * back. - */ - if (test_and_clear_thread_flag(TIF_RESTORE_SIGMASK)) - set_current_blocked(¤t->saved_sigmask); + restore_saved_sigmask(); } asmlinkage void @@ -679,7 +682,5 @@ do_notify_resume(struct pt_regs *regs, unsigned int thread_flags, int syscall) if (thread_flags & _TIF_NOTIFY_RESUME) { clear_thread_flag(TIF_NOTIFY_RESUME); tracehook_notify_resume(regs); - if (current->replacement_session_keyring) - key_replace_session_keyring(); } } |