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 <h-shimamoto@ct.jp.nec.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

1 files changed, 195 insertions, 170 deletions

diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c
index 9dabd00e9805..dd77ac0cac46 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;