From 3b4b75700a245d0d48fc52a4d2f67d3155812aba Mon Sep 17 00:00:00 2001 From: Hiroshi Shimamoto Date: Fri, 23 Jan 2009 15:50:38 -0800 Subject: [PATCH] x86: ia32_signal: use {get|put}_user_try and catch Impact: use new framework Use {get|put}_user_try, catch, and _ex in arch/x86/ia32/ia32_signal.c. Note: this patch contains "WARNING: line over 80 characters", because when introducing new block I insert an indent to avoid mistakes by edit. Signed-off-by: Hiroshi Shimamoto Signed-off-by: H. Peter Anvin --- arch/x86/ia32/ia32_signal.c | 365 +++++++++++++++++++----------------- 1 file changed, 195 insertions(+), 170 deletions(-) diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c index 9dabd00e980..dd77ac0cac4 100644 --- a/arch/x86/ia32/ia32_signal.c +++ b/arch/x86/ia32/ia32_signal.c @@ -46,78 +46,83 @@ void signal_fault(struct pt_regs *regs, void __user *frame, char *where); int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from) { - int err; + int err = 0; if (!access_ok(VERIFY_WRITE, to, sizeof(compat_siginfo_t))) return -EFAULT; - /* If you change siginfo_t structure, please make sure that - this code is fixed accordingly. - It should never copy any pad contained in the structure - to avoid security leaks, but must copy the generic - 3 ints plus the relevant union member. */ - err = __put_user(from->si_signo, &to->si_signo); - err |= __put_user(from->si_errno, &to->si_errno); - err |= __put_user((short)from->si_code, &to->si_code); - - if (from->si_code < 0) { - err |= __put_user(from->si_pid, &to->si_pid); - err |= __put_user(from->si_uid, &to->si_uid); - err |= __put_user(ptr_to_compat(from->si_ptr), &to->si_ptr); - } else { - /* - * First 32bits of unions are always present: - * si_pid === si_band === si_tid === si_addr(LS half) - */ - err |= __put_user(from->_sifields._pad[0], - &to->_sifields._pad[0]); - switch (from->si_code >> 16) { - case __SI_FAULT >> 16: - break; - case __SI_CHLD >> 16: - err |= __put_user(from->si_utime, &to->si_utime); - err |= __put_user(from->si_stime, &to->si_stime); - err |= __put_user(from->si_status, &to->si_status); - /* FALL THROUGH */ - default: - case __SI_KILL >> 16: - err |= __put_user(from->si_uid, &to->si_uid); - break; - case __SI_POLL >> 16: - err |= __put_user(from->si_fd, &to->si_fd); - break; - case __SI_TIMER >> 16: - err |= __put_user(from->si_overrun, &to->si_overrun); - err |= __put_user(ptr_to_compat(from->si_ptr), - &to->si_ptr); - break; - /* This is not generated by the kernel as of now. */ - case __SI_RT >> 16: - case __SI_MESGQ >> 16: - err |= __put_user(from->si_uid, &to->si_uid); - err |= __put_user(from->si_int, &to->si_int); - break; + put_user_try { + /* If you change siginfo_t structure, please make sure that + this code is fixed accordingly. + It should never copy any pad contained in the structure + to avoid security leaks, but must copy the generic + 3 ints plus the relevant union member. */ + put_user_ex(from->si_signo, &to->si_signo); + put_user_ex(from->si_errno, &to->si_errno); + put_user_ex((short)from->si_code, &to->si_code); + + if (from->si_code < 0) { + put_user_ex(from->si_pid, &to->si_pid); + put_user_ex(from->si_uid, &to->si_uid); + put_user_ex(ptr_to_compat(from->si_ptr), &to->si_ptr); + } else { + /* + * First 32bits of unions are always present: + * si_pid === si_band === si_tid === si_addr(LS half) + */ + put_user_ex(from->_sifields._pad[0], + &to->_sifields._pad[0]); + switch (from->si_code >> 16) { + case __SI_FAULT >> 16: + break; + case __SI_CHLD >> 16: + put_user_ex(from->si_utime, &to->si_utime); + put_user_ex(from->si_stime, &to->si_stime); + put_user_ex(from->si_status, &to->si_status); + /* FALL THROUGH */ + default: + case __SI_KILL >> 16: + put_user_ex(from->si_uid, &to->si_uid); + break; + case __SI_POLL >> 16: + put_user_ex(from->si_fd, &to->si_fd); + break; + case __SI_TIMER >> 16: + put_user_ex(from->si_overrun, &to->si_overrun); + put_user_ex(ptr_to_compat(from->si_ptr), + &to->si_ptr); + break; + /* This is not generated by the kernel as of now. */ + case __SI_RT >> 16: + case __SI_MESGQ >> 16: + put_user_ex(from->si_uid, &to->si_uid); + put_user_ex(from->si_int, &to->si_int); + break; + } } - } + } put_user_catch(err); + return err; } int copy_siginfo_from_user32(siginfo_t *to, compat_siginfo_t __user *from) { - int err; + int err = 0; u32 ptr32; if (!access_ok(VERIFY_READ, from, sizeof(compat_siginfo_t))) return -EFAULT; - err = __get_user(to->si_signo, &from->si_signo); - err |= __get_user(to->si_errno, &from->si_errno); - err |= __get_user(to->si_code, &from->si_code); + get_user_try { + get_user_ex(to->si_signo, &from->si_signo); + get_user_ex(to->si_errno, &from->si_errno); + get_user_ex(to->si_code, &from->si_code); - err |= __get_user(to->si_pid, &from->si_pid); - err |= __get_user(to->si_uid, &from->si_uid); - err |= __get_user(ptr32, &from->si_ptr); - to->si_ptr = compat_ptr(ptr32); + get_user_ex(to->si_pid, &from->si_pid); + get_user_ex(to->si_uid, &from->si_uid); + get_user_ex(ptr32, &from->si_ptr); + to->si_ptr = compat_ptr(ptr32); + } get_user_catch(err); return err; } @@ -142,17 +147,23 @@ asmlinkage long sys32_sigaltstack(const stack_ia32_t __user *uss_ptr, struct pt_regs *regs) { stack_t uss, uoss; - int ret; + int ret, err = 0; mm_segment_t seg; if (uss_ptr) { u32 ptr; memset(&uss, 0, sizeof(stack_t)); - if (!access_ok(VERIFY_READ, uss_ptr, sizeof(stack_ia32_t)) || - __get_user(ptr, &uss_ptr->ss_sp) || - __get_user(uss.ss_flags, &uss_ptr->ss_flags) || - __get_user(uss.ss_size, &uss_ptr->ss_size)) + if (!access_ok(VERIFY_READ, uss_ptr, sizeof(stack_ia32_t))) + return -EFAULT; + + get_user_try { + get_user_ex(ptr, &uss_ptr->ss_sp); + get_user_ex(uss.ss_flags, &uss_ptr->ss_flags); + get_user_ex(uss.ss_size, &uss_ptr->ss_size); + } get_user_catch(err); + + if (err) return -EFAULT; uss.ss_sp = compat_ptr(ptr); } @@ -161,10 +172,16 @@ asmlinkage long sys32_sigaltstack(const stack_ia32_t __user *uss_ptr, ret = do_sigaltstack(uss_ptr ? &uss : NULL, &uoss, regs->sp); set_fs(seg); if (ret >= 0 && uoss_ptr) { - if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(stack_ia32_t)) || - __put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) || - __put_user(uoss.ss_flags, &uoss_ptr->ss_flags) || - __put_user(uoss.ss_size, &uoss_ptr->ss_size)) + if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(stack_ia32_t))) + return -EFAULT; + + put_user_try { + put_user_ex(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp); + put_user_ex(uoss.ss_flags, &uoss_ptr->ss_flags); + put_user_ex(uoss.ss_size, &uoss_ptr->ss_size); + } put_user_catch(err); + + if (err) ret = -EFAULT; } return ret; @@ -174,18 +191,18 @@ asmlinkage long sys32_sigaltstack(const stack_ia32_t __user *uss_ptr, * Do a signal return; undo the signal stack. */ #define COPY(x) { \ - err |= __get_user(regs->x, &sc->x); \ + get_user_ex(regs->x, &sc->x); \ } #define COPY_SEG_CPL3(seg) { \ unsigned short tmp; \ - err |= __get_user(tmp, &sc->seg); \ + get_user_ex(tmp, &sc->seg); \ regs->seg = tmp | 3; \ } #define RELOAD_SEG(seg) { \ unsigned int cur, pre; \ - err |= __get_user(pre, &sc->seg); \ + get_user_ex(pre, &sc->seg); \ savesegment(seg, cur); \ pre |= 3; \ if (pre != cur) \ @@ -209,39 +226,42 @@ static int ia32_restore_sigcontext(struct pt_regs *regs, sc, sc->err, sc->ip, sc->cs, sc->flags); #endif - /* - * Reload fs and gs if they have changed in the signal - * handler. This does not handle long fs/gs base changes in - * the handler, but does not clobber them at least in the - * normal case. - */ - err |= __get_user(gs, &sc->gs); - gs |= 3; - savesegment(gs, oldgs); - if (gs != oldgs) - load_gs_index(gs); - - RELOAD_SEG(fs); - RELOAD_SEG(ds); - RELOAD_SEG(es); - - COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); - COPY(dx); COPY(cx); COPY(ip); - /* Don't touch extended registers */ - - COPY_SEG_CPL3(cs); - COPY_SEG_CPL3(ss); - - err |= __get_user(tmpflags, &sc->flags); - regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); - /* disable syscall checks */ - regs->orig_ax = -1; - - err |= __get_user(tmp, &sc->fpstate); - buf = compat_ptr(tmp); - err |= restore_i387_xstate_ia32(buf); - - err |= __get_user(*pax, &sc->ax); + get_user_try { + /* + * Reload fs and gs if they have changed in the signal + * handler. This does not handle long fs/gs base changes in + * the handler, but does not clobber them at least in the + * normal case. + */ + get_user_ex(gs, &sc->gs); + gs |= 3; + savesegment(gs, oldgs); + if (gs != oldgs) + load_gs_index(gs); + + RELOAD_SEG(fs); + RELOAD_SEG(ds); + RELOAD_SEG(es); + + COPY(di); COPY(si); COPY(bp); COPY(sp); COPY(bx); + COPY(dx); COPY(cx); COPY(ip); + /* Don't touch extended registers */ + + COPY_SEG_CPL3(cs); + COPY_SEG_CPL3(ss); + + get_user_ex(tmpflags, &sc->flags); + regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS); + /* disable syscall checks */ + regs->orig_ax = -1; + + get_user_ex(tmp, &sc->fpstate); + buf = compat_ptr(tmp); + err |= restore_i387_xstate_ia32(buf); + + get_user_ex(*pax, &sc->ax); + } get_user_catch(err); + return err; } @@ -319,36 +339,38 @@ static int ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc, { int tmp, err = 0; - savesegment(gs, tmp); - err |= __put_user(tmp, (unsigned int __user *)&sc->gs); - savesegment(fs, tmp); - err |= __put_user(tmp, (unsigned int __user *)&sc->fs); - savesegment(ds, tmp); - err |= __put_user(tmp, (unsigned int __user *)&sc->ds); - savesegment(es, tmp); - err |= __put_user(tmp, (unsigned int __user *)&sc->es); - - err |= __put_user(regs->di, &sc->di); - err |= __put_user(regs->si, &sc->si); - err |= __put_user(regs->bp, &sc->bp); - err |= __put_user(regs->sp, &sc->sp); - err |= __put_user(regs->bx, &sc->bx); - err |= __put_user(regs->dx, &sc->dx); - err |= __put_user(regs->cx, &sc->cx); - err |= __put_user(regs->ax, &sc->ax); - err |= __put_user(current->thread.trap_no, &sc->trapno); - err |= __put_user(current->thread.error_code, &sc->err); - err |= __put_user(regs->ip, &sc->ip); - err |= __put_user(regs->cs, (unsigned int __user *)&sc->cs); - err |= __put_user(regs->flags, &sc->flags); - err |= __put_user(regs->sp, &sc->sp_at_signal); - err |= __put_user(regs->ss, (unsigned int __user *)&sc->ss); - - err |= __put_user(ptr_to_compat(fpstate), &sc->fpstate); - - /* non-iBCS2 extensions.. */ - err |= __put_user(mask, &sc->oldmask); - err |= __put_user(current->thread.cr2, &sc->cr2); + put_user_try { + savesegment(gs, tmp); + put_user_ex(tmp, (unsigned int __user *)&sc->gs); + savesegment(fs, tmp); + put_user_ex(tmp, (unsigned int __user *)&sc->fs); + savesegment(ds, tmp); + put_user_ex(tmp, (unsigned int __user *)&sc->ds); + savesegment(es, tmp); + put_user_ex(tmp, (unsigned int __user *)&sc->es); + + put_user_ex(regs->di, &sc->di); + put_user_ex(regs->si, &sc->si); + put_user_ex(regs->bp, &sc->bp); + put_user_ex(regs->sp, &sc->sp); + put_user_ex(regs->bx, &sc->bx); + put_user_ex(regs->dx, &sc->dx); + put_user_ex(regs->cx, &sc->cx); + put_user_ex(regs->ax, &sc->ax); + put_user_ex(current->thread.trap_no, &sc->trapno); + put_user_ex(current->thread.error_code, &sc->err); + put_user_ex(regs->ip, &sc->ip); + put_user_ex(regs->cs, (unsigned int __user *)&sc->cs); + put_user_ex(regs->flags, &sc->flags); + put_user_ex(regs->sp, &sc->sp_at_signal); + put_user_ex(regs->ss, (unsigned int __user *)&sc->ss); + + put_user_ex(ptr_to_compat(fpstate), &sc->fpstate); + + /* non-iBCS2 extensions.. */ + put_user_ex(mask, &sc->oldmask); + put_user_ex(current->thread.cr2, &sc->cr2); + } put_user_catch(err); return err; } @@ -437,13 +459,17 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka, else restorer = &frame->retcode; } - err |= __put_user(ptr_to_compat(restorer), &frame->pretcode); - /* - * These are actually not used anymore, but left because some - * gdb versions depend on them as a marker. - */ - err |= __put_user(*((u64 *)&code), (u64 *)frame->retcode); + put_user_try { + put_user_ex(ptr_to_compat(restorer), &frame->pretcode); + + /* + * These are actually not used anymore, but left because some + * gdb versions depend on them as a marker. + */ + put_user_ex(*((u64 *)&code), (u64 *)frame->retcode); + } put_user_catch(err); + if (err) return -EFAULT; @@ -496,41 +522,40 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info, if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame))) return -EFAULT; - err |= __put_user(sig, &frame->sig); - err |= __put_user(ptr_to_compat(&frame->info), &frame->pinfo); - err |= __put_user(ptr_to_compat(&frame->uc), &frame->puc); - err |= copy_siginfo_to_user32(&frame->info, info); - if (err) - return -EFAULT; + put_user_try { + put_user_ex(sig, &frame->sig); + put_user_ex(ptr_to_compat(&frame->info), &frame->pinfo); + put_user_ex(ptr_to_compat(&frame->uc), &frame->puc); + err |= copy_siginfo_to_user32(&frame->info, info); - /* Create the ucontext. */ - if (cpu_has_xsave) - err |= __put_user(UC_FP_XSTATE, &frame->uc.uc_flags); - else - err |= __put_user(0, &frame->uc.uc_flags); - err |= __put_user(0, &frame->uc.uc_link); - err |= __put_user(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); - err |= __put_user(sas_ss_flags(regs->sp), - &frame->uc.uc_stack.ss_flags); - err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size); - err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, fpstate, - regs, set->sig[0]); - err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); - if (err) - return -EFAULT; + /* Create the ucontext. */ + if (cpu_has_xsave) + put_user_ex(UC_FP_XSTATE, &frame->uc.uc_flags); + else + put_user_ex(0, &frame->uc.uc_flags); + put_user_ex(0, &frame->uc.uc_link); + put_user_ex(current->sas_ss_sp, &frame->uc.uc_stack.ss_sp); + put_user_ex(sas_ss_flags(regs->sp), + &frame->uc.uc_stack.ss_flags); + put_user_ex(current->sas_ss_size, &frame->uc.uc_stack.ss_size); + err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, fpstate, + regs, set->sig[0]); + err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set)); + + if (ka->sa.sa_flags & SA_RESTORER) + restorer = ka->sa.sa_restorer; + else + restorer = VDSO32_SYMBOL(current->mm->context.vdso, + rt_sigreturn); + put_user_ex(ptr_to_compat(restorer), &frame->pretcode); + + /* + * Not actually used anymore, but left because some gdb + * versions need it. + */ + put_user_ex(*((u64 *)&code), (u64 *)frame->retcode); + } put_user_catch(err); - if (ka->sa.sa_flags & SA_RESTORER) - restorer = ka->sa.sa_restorer; - else - restorer = VDSO32_SYMBOL(current->mm->context.vdso, - rt_sigreturn); - err |= __put_user(ptr_to_compat(restorer), &frame->pretcode); - - /* - * Not actually used anymore, but left because some gdb - * versions need it. - */ - err |= __put_user(*((u64 *)&code), (u64 *)frame->retcode); if (err) return -EFAULT; -- 2.46.0