diff options
| -rw-r--r-- | arch/x86/ia32/ia32_signal.c | 2 | ||||
| -rw-r--r-- | arch/x86/include/asm/fpu/signal.h | 6 | ||||
| -rw-r--r-- | arch/x86/include/asm/signal.h | 4 | ||||
| -rw-r--r-- | arch/x86/kernel/signal.c | 20 | ||||
| -rw-r--r-- | arch/x86/kernel/signal_compat.c | 34 | ||||
| -rw-r--r-- | kernel/signal.c | 7 |
6 files changed, 60 insertions, 13 deletions
diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index 2f29f4e407c3..cb13c0564ea7 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -378,7 +378,7 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig, put_user_ex(*((u64 *)&code), (u64 __user *)frame->retcode); } put_user_catch(err); - err |= copy_siginfo_to_user32(&frame->info, &ksig->info); + err |= __copy_siginfo_to_user32(&frame->info, &ksig->info, false); err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, fpstate, regs, set->sig[0]); err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); diff --git a/arch/x86/include/asm/fpu/signal.h b/arch/x86/include/asm/fpu/signal.h index 0e970d00dfcd..20a1fbf7fe4e 100644 --- a/arch/x86/include/asm/fpu/signal.h +++ b/arch/x86/include/asm/fpu/signal.h @@ -19,6 +19,12 @@ int ia32_setup_frame(int sig, struct ksignal *ksig, # define ia32_setup_rt_frame __setup_rt_frame #endif +#ifdef CONFIG_COMPAT +int __copy_siginfo_to_user32(compat_siginfo_t __user *to, + const siginfo_t *from, bool x32_ABI); +#endif + + extern void convert_from_fxsr(struct user_i387_ia32_struct *env, struct task_struct *tsk); extern void convert_to_fxsr(struct task_struct *tsk, diff --git a/arch/x86/include/asm/signal.h b/arch/x86/include/asm/signal.h index dd1e7d6387ab..8af22be0fe61 100644 --- a/arch/x86/include/asm/signal.h +++ b/arch/x86/include/asm/signal.h @@ -23,6 +23,10 @@ typedef struct { unsigned long sig[_NSIG_WORDS]; } sigset_t; +/* non-uapi in-kernel SA_FLAGS for those indicates ABI for a signal frame */ +#define SA_IA32_ABI 0x02000000u +#define SA_X32_ABI 0x01000000u + #ifndef CONFIG_COMPAT typedef sigset_t compat_sigset_t; #endif diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c index 04cb3212db2d..b1a5d252d482 100644 --- a/arch/x86/kernel/signal.c +++ b/arch/x86/kernel/signal.c @@ -42,6 +42,7 @@ #include <asm/syscalls.h> #include <asm/sigframe.h> +#include <asm/signal.h> #define COPY(x) do { \ get_user_ex(regs->x, &sc->x); \ @@ -547,7 +548,7 @@ static int x32_setup_rt_frame(struct ksignal *ksig, return -EFAULT; if (ksig->ka.sa.sa_flags & SA_SIGINFO) { - if (copy_siginfo_to_user32(&frame->info, &ksig->info)) + if (__copy_siginfo_to_user32(&frame->info, &ksig->info, true)) return -EFAULT; } @@ -660,20 +661,21 @@ badframe: return 0; } -static inline int is_ia32_compat_frame(void) +static inline int is_ia32_compat_frame(struct ksignal *ksig) { return IS_ENABLED(CONFIG_IA32_EMULATION) && - test_thread_flag(TIF_IA32); + ksig->ka.sa.sa_flags & SA_IA32_ABI; } -static inline int is_ia32_frame(void) +static inline int is_ia32_frame(struct ksignal *ksig) { - return IS_ENABLED(CONFIG_X86_32) || is_ia32_compat_frame(); + return IS_ENABLED(CONFIG_X86_32) || is_ia32_compat_frame(ksig); } -static inline int is_x32_frame(void) +static inline int is_x32_frame(struct ksignal *ksig) { - return IS_ENABLED(CONFIG_X86_X32_ABI) && test_thread_flag(TIF_X32); + return IS_ENABLED(CONFIG_X86_X32_ABI) && + ksig->ka.sa.sa_flags & SA_X32_ABI; } static int @@ -684,12 +686,12 @@ setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs) compat_sigset_t *cset = (compat_sigset_t *) set; /* Set up the stack frame */ - if (is_ia32_frame()) { + if (is_ia32_frame(ksig)) { if (ksig->ka.sa.sa_flags & SA_SIGINFO) return ia32_setup_rt_frame(usig, ksig, cset, regs); else return ia32_setup_frame(usig, ksig, cset, regs); - } else if (is_x32_frame()) { + } else if (is_x32_frame(ksig)) { return x32_setup_rt_frame(ksig, cset, regs); } else { return __setup_rt_frame(ksig->sig, ksig, set, regs); diff --git a/arch/x86/kernel/signal_compat.c b/arch/x86/kernel/signal_compat.c index b44564bf86a8..40df33753bae 100644 --- a/arch/x86/kernel/signal_compat.c +++ b/arch/x86/kernel/signal_compat.c @@ -1,5 +1,6 @@ #include <linux/compat.h> #include <linux/uaccess.h> +#include <linux/ptrace.h> /* * The compat_siginfo_t structure and handing code is very easy @@ -92,10 +93,31 @@ static inline void signal_compat_build_tests(void) /* any new si_fields should be added here */ } -int copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from) +void sigaction_compat_abi(struct k_sigaction *act, struct k_sigaction *oact) +{ + /* Don't leak in-kernel non-uapi flags to user-space */ + if (oact) + oact->sa.sa_flags &= ~(SA_IA32_ABI | SA_X32_ABI); + + if (!act) + return; + + /* Don't let flags to be set from userspace */ + act->sa.sa_flags &= ~(SA_IA32_ABI | SA_X32_ABI); + + if (user_64bit_mode(current_pt_regs())) + return; + + if (in_ia32_syscall()) + act->sa.sa_flags |= SA_IA32_ABI; + if (in_x32_syscall()) + act->sa.sa_flags |= SA_X32_ABI; +} + +int __copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from, + bool x32_ABI) { int err = 0; - bool ia32 = test_thread_flag(TIF_IA32); signal_compat_build_tests(); @@ -146,7 +168,7 @@ int copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from) put_user_ex(from->si_arch, &to->si_arch); break; case __SI_CHLD >> 16: - if (ia32) { + if (!x32_ABI) { put_user_ex(from->si_utime, &to->si_utime); put_user_ex(from->si_stime, &to->si_stime); } else { @@ -180,6 +202,12 @@ int copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from) return err; } +/* from syscall's path, where we know the ABI */ +int copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from) +{ + return __copy_siginfo_to_user32(to, from, in_x32_syscall()); +} + int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from) { int err = 0; diff --git a/kernel/signal.c b/kernel/signal.c index af21afc00d08..75761acc77cf 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -3044,6 +3044,11 @@ void kernel_sigaction(int sig, __sighandler_t action) } EXPORT_SYMBOL(kernel_sigaction); +void __weak sigaction_compat_abi(struct k_sigaction *act, + struct k_sigaction *oact) +{ +} + int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) { struct task_struct *p = current, *t; @@ -3059,6 +3064,8 @@ int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact) if (oact) *oact = *k; + sigaction_compat_abi(act, oact); + if (act) { sigdelsetmask(&act->sa.sa_mask, sigmask(SIGKILL) | sigmask(SIGSTOP)); |