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-rw-r--r--arch/sparc/kernel/signal32.c786
1 files changed, 786 insertions, 0 deletions
diff --git a/arch/sparc/kernel/signal32.c b/arch/sparc/kernel/signal32.c
new file mode 100644
index 0000000000..a23cdd7459
--- /dev/null
+++ b/arch/sparc/kernel/signal32.c
@@ -0,0 +1,786 @@
+// SPDX-License-Identifier: GPL-2.0
+/* arch/sparc64/kernel/signal32.c
+ *
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
+ * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx)
+ * Copyright (C) 1997 Eddie C. Dost (ecd@skynet.be)
+ * Copyright (C) 1997,1998 Jakub Jelinek (jj@sunsite.mff.cuni.cz)
+ */
+
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/signal.h>
+#include <linux/errno.h>
+#include <linux/wait.h>
+#include <linux/ptrace.h>
+#include <linux/unistd.h>
+#include <linux/mm.h>
+#include <linux/tty.h>
+#include <linux/binfmts.h>
+#include <linux/compat.h>
+#include <linux/bitops.h>
+
+#include <linux/uaccess.h>
+#include <asm/ptrace.h>
+#include <asm/psrcompat.h>
+#include <asm/fpumacro.h>
+#include <asm/visasm.h>
+#include <asm/compat_signal.h>
+#include <asm/switch_to.h>
+
+#include "sigutil.h"
+#include "kernel.h"
+
+/* This magic should be in g_upper[0] for all upper parts
+ * to be valid.
+ */
+#define SIGINFO_EXTRA_V8PLUS_MAGIC 0x130e269
+typedef struct {
+ unsigned int g_upper[8];
+ unsigned int o_upper[8];
+ unsigned int asi;
+} siginfo_extra_v8plus_t;
+
+struct signal_frame32 {
+ struct sparc_stackf32 ss;
+ __siginfo32_t info;
+ /* __siginfo_fpu_t * */ u32 fpu_save;
+ unsigned int insns[2];
+ unsigned int extramask[_COMPAT_NSIG_WORDS - 1];
+ unsigned int extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
+ /* Only valid if (info.si_regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
+ siginfo_extra_v8plus_t v8plus;
+ /* __siginfo_rwin_t * */u32 rwin_save;
+} __attribute__((aligned(8)));
+
+struct rt_signal_frame32 {
+ struct sparc_stackf32 ss;
+ compat_siginfo_t info;
+ struct pt_regs32 regs;
+ compat_sigset_t mask;
+ /* __siginfo_fpu_t * */ u32 fpu_save;
+ unsigned int insns[2];
+ compat_stack_t stack;
+ unsigned int extra_size; /* Should be sizeof(siginfo_extra_v8plus_t) */
+ /* Only valid if (regs.psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS */
+ siginfo_extra_v8plus_t v8plus;
+ /* __siginfo_rwin_t * */u32 rwin_save;
+} __attribute__((aligned(8)));
+
+/* Checks if the fp is valid. We always build signal frames which are
+ * 16-byte aligned, therefore we can always enforce that the restore
+ * frame has that property as well.
+ */
+static bool invalid_frame_pointer(void __user *fp, int fplen)
+{
+ if ((((unsigned long) fp) & 15) ||
+ ((unsigned long)fp) > 0x100000000ULL - fplen)
+ return true;
+ return false;
+}
+
+void do_sigreturn32(struct pt_regs *regs)
+{
+ struct signal_frame32 __user *sf;
+ compat_uptr_t fpu_save;
+ compat_uptr_t rwin_save;
+ unsigned int psr, ufp;
+ unsigned int pc, npc;
+ sigset_t set;
+ compat_sigset_t seta;
+ int err, i;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ synchronize_user_stack();
+
+ regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
+ sf = (struct signal_frame32 __user *) regs->u_regs[UREG_FP];
+
+ /* 1. Make sure we are not getting garbage from the user */
+ if (invalid_frame_pointer(sf, sizeof(*sf)))
+ goto segv;
+
+ if (get_user(ufp, &sf->info.si_regs.u_regs[UREG_FP]))
+ goto segv;
+
+ if (ufp & 0x7)
+ goto segv;
+
+ if (__get_user(pc, &sf->info.si_regs.pc) ||
+ __get_user(npc, &sf->info.si_regs.npc))
+ goto segv;
+
+ if ((pc | npc) & 3)
+ goto segv;
+
+ if (test_thread_flag(TIF_32BIT)) {
+ pc &= 0xffffffff;
+ npc &= 0xffffffff;
+ }
+ regs->tpc = pc;
+ regs->tnpc = npc;
+
+ /* 2. Restore the state */
+ err = __get_user(regs->y, &sf->info.si_regs.y);
+ err |= __get_user(psr, &sf->info.si_regs.psr);
+
+ for (i = UREG_G1; i <= UREG_I7; i++)
+ err |= __get_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
+ if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
+ err |= __get_user(i, &sf->v8plus.g_upper[0]);
+ if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
+ unsigned long asi;
+
+ for (i = UREG_G1; i <= UREG_I7; i++)
+ err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
+ err |= __get_user(asi, &sf->v8plus.asi);
+ regs->tstate &= ~TSTATE_ASI;
+ regs->tstate |= ((asi & 0xffUL) << 24UL);
+ }
+ }
+
+ /* User can only change condition codes in %tstate. */
+ regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
+ regs->tstate |= psr_to_tstate_icc(psr);
+
+ /* Prevent syscall restart. */
+ pt_regs_clear_syscall(regs);
+
+ err |= __get_user(fpu_save, &sf->fpu_save);
+ if (!err && fpu_save)
+ err |= restore_fpu_state(regs, compat_ptr(fpu_save));
+ err |= __get_user(rwin_save, &sf->rwin_save);
+ if (!err && rwin_save) {
+ if (restore_rwin_state(compat_ptr(rwin_save)))
+ goto segv;
+ }
+ err |= __get_user(seta.sig[0], &sf->info.si_mask);
+ err |= copy_from_user(&seta.sig[1], &sf->extramask,
+ (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
+ if (err)
+ goto segv;
+
+ set.sig[0] = seta.sig[0] + (((long)seta.sig[1]) << 32);
+ set_current_blocked(&set);
+ return;
+
+segv:
+ force_sig(SIGSEGV);
+}
+
+asmlinkage void do_rt_sigreturn32(struct pt_regs *regs)
+{
+ struct rt_signal_frame32 __user *sf;
+ unsigned int psr, pc, npc, ufp;
+ compat_uptr_t fpu_save;
+ compat_uptr_t rwin_save;
+ sigset_t set;
+ int err, i;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ synchronize_user_stack();
+ regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
+ sf = (struct rt_signal_frame32 __user *) regs->u_regs[UREG_FP];
+
+ /* 1. Make sure we are not getting garbage from the user */
+ if (invalid_frame_pointer(sf, sizeof(*sf)))
+ goto segv;
+
+ if (get_user(ufp, &sf->regs.u_regs[UREG_FP]))
+ goto segv;
+
+ if (ufp & 0x7)
+ goto segv;
+
+ if (__get_user(pc, &sf->regs.pc) ||
+ __get_user(npc, &sf->regs.npc))
+ goto segv;
+
+ if ((pc | npc) & 3)
+ goto segv;
+
+ if (test_thread_flag(TIF_32BIT)) {
+ pc &= 0xffffffff;
+ npc &= 0xffffffff;
+ }
+ regs->tpc = pc;
+ regs->tnpc = npc;
+
+ /* 2. Restore the state */
+ err = __get_user(regs->y, &sf->regs.y);
+ err |= __get_user(psr, &sf->regs.psr);
+
+ for (i = UREG_G1; i <= UREG_I7; i++)
+ err |= __get_user(regs->u_regs[i], &sf->regs.u_regs[i]);
+ if ((psr & (PSR_VERS|PSR_IMPL)) == PSR_V8PLUS) {
+ err |= __get_user(i, &sf->v8plus.g_upper[0]);
+ if (i == SIGINFO_EXTRA_V8PLUS_MAGIC) {
+ unsigned long asi;
+
+ for (i = UREG_G1; i <= UREG_I7; i++)
+ err |= __get_user(((u32 *)regs->u_regs)[2*i], &sf->v8plus.g_upper[i]);
+ err |= __get_user(asi, &sf->v8plus.asi);
+ regs->tstate &= ~TSTATE_ASI;
+ regs->tstate |= ((asi & 0xffUL) << 24UL);
+ }
+ }
+
+ /* User can only change condition codes in %tstate. */
+ regs->tstate &= ~(TSTATE_ICC|TSTATE_XCC);
+ regs->tstate |= psr_to_tstate_icc(psr);
+
+ /* Prevent syscall restart. */
+ pt_regs_clear_syscall(regs);
+
+ err |= __get_user(fpu_save, &sf->fpu_save);
+ if (!err && fpu_save)
+ err |= restore_fpu_state(regs, compat_ptr(fpu_save));
+ err |= get_compat_sigset(&set, &sf->mask);
+ err |= compat_restore_altstack(&sf->stack);
+ if (err)
+ goto segv;
+
+ err |= __get_user(rwin_save, &sf->rwin_save);
+ if (!err && rwin_save) {
+ if (restore_rwin_state(compat_ptr(rwin_save)))
+ goto segv;
+ }
+
+ set_current_blocked(&set);
+ return;
+segv:
+ force_sig(SIGSEGV);
+}
+
+static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs, unsigned long framesize)
+{
+ unsigned long sp;
+
+ regs->u_regs[UREG_FP] &= 0x00000000ffffffffUL;
+ sp = regs->u_regs[UREG_FP];
+
+ /*
+ * If we are on the alternate signal stack and would overflow it, don't.
+ * Return an always-bogus address instead so we will die with SIGSEGV.
+ */
+ if (on_sig_stack(sp) && !likely(on_sig_stack(sp - framesize)))
+ return (void __user *) -1L;
+
+ /* This is the X/Open sanctioned signal stack switching. */
+ sp = sigsp(sp, ksig) - framesize;
+
+ /* Always align the stack frame. This handles two cases. First,
+ * sigaltstack need not be mindful of platform specific stack
+ * alignment. Second, if we took this signal because the stack
+ * is not aligned properly, we'd like to take the signal cleanly
+ * and report that.
+ */
+ sp &= ~15UL;
+
+ return (void __user *) sp;
+}
+
+/* The I-cache flush instruction only works in the primary ASI, which
+ * right now is the nucleus, aka. kernel space.
+ *
+ * Therefore we have to kick the instructions out using the kernel
+ * side linear mapping of the physical address backing the user
+ * instructions.
+ */
+static void flush_signal_insns(unsigned long address)
+{
+ unsigned long pstate, paddr;
+ pte_t *ptep, pte;
+ pgd_t *pgdp;
+ p4d_t *p4dp;
+ pud_t *pudp;
+ pmd_t *pmdp;
+
+ /* Commit all stores of the instructions we are about to flush. */
+ wmb();
+
+ /* Disable cross-call reception. In this way even a very wide
+ * munmap() on another cpu can't tear down the page table
+ * hierarchy from underneath us, since that can't complete
+ * until the IPI tlb flush returns.
+ */
+
+ __asm__ __volatile__("rdpr %%pstate, %0" : "=r" (pstate));
+ __asm__ __volatile__("wrpr %0, %1, %%pstate"
+ : : "r" (pstate), "i" (PSTATE_IE));
+
+ pgdp = pgd_offset(current->mm, address);
+ if (pgd_none(*pgdp))
+ goto out_irqs_on;
+ p4dp = p4d_offset(pgdp, address);
+ if (p4d_none(*p4dp))
+ goto out_irqs_on;
+ pudp = pud_offset(p4dp, address);
+ if (pud_none(*pudp))
+ goto out_irqs_on;
+ pmdp = pmd_offset(pudp, address);
+ if (pmd_none(*pmdp))
+ goto out_irqs_on;
+
+ ptep = pte_offset_map(pmdp, address);
+ if (!ptep)
+ goto out_irqs_on;
+ pte = *ptep;
+ if (!pte_present(pte))
+ goto out_unmap;
+
+ paddr = (unsigned long) page_address(pte_page(pte));
+
+ __asm__ __volatile__("flush %0 + %1"
+ : /* no outputs */
+ : "r" (paddr),
+ "r" (address & (PAGE_SIZE - 1))
+ : "memory");
+
+out_unmap:
+ pte_unmap(ptep);
+out_irqs_on:
+ __asm__ __volatile__("wrpr %0, 0x0, %%pstate" : : "r" (pstate));
+
+}
+
+static int setup_frame32(struct ksignal *ksig, struct pt_regs *regs,
+ sigset_t *oldset)
+{
+ struct signal_frame32 __user *sf;
+ int i, err, wsaved;
+ void __user *tail;
+ int sigframe_size;
+ u32 psr;
+ compat_sigset_t seta;
+
+ /* 1. Make sure everything is clean */
+ synchronize_user_stack();
+ save_and_clear_fpu();
+
+ wsaved = get_thread_wsaved();
+
+ sigframe_size = sizeof(*sf);
+ if (current_thread_info()->fpsaved[0] & FPRS_FEF)
+ sigframe_size += sizeof(__siginfo_fpu_t);
+ if (wsaved)
+ sigframe_size += sizeof(__siginfo_rwin_t);
+
+ sf = (struct signal_frame32 __user *)
+ get_sigframe(ksig, regs, sigframe_size);
+
+ if (invalid_frame_pointer(sf, sigframe_size)) {
+ if (show_unhandled_signals)
+ pr_info("%s[%d] bad frame in setup_frame32: %08lx TPC %08lx O7 %08lx\n",
+ current->comm, current->pid, (unsigned long)sf,
+ regs->tpc, regs->u_regs[UREG_I7]);
+ force_sigsegv(ksig->sig);
+ return -EINVAL;
+ }
+
+ tail = (sf + 1);
+
+ /* 2. Save the current process state */
+ if (test_thread_flag(TIF_32BIT)) {
+ regs->tpc &= 0xffffffff;
+ regs->tnpc &= 0xffffffff;
+ }
+ err = put_user(regs->tpc, &sf->info.si_regs.pc);
+ err |= __put_user(regs->tnpc, &sf->info.si_regs.npc);
+ err |= __put_user(regs->y, &sf->info.si_regs.y);
+ psr = tstate_to_psr(regs->tstate);
+ if (current_thread_info()->fpsaved[0] & FPRS_FEF)
+ psr |= PSR_EF;
+ err |= __put_user(psr, &sf->info.si_regs.psr);
+ for (i = 0; i < 16; i++)
+ err |= __put_user(regs->u_regs[i], &sf->info.si_regs.u_regs[i]);
+ err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
+ err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
+ for (i = 1; i < 16; i++)
+ err |= __put_user(((u32 *)regs->u_regs)[2*i],
+ &sf->v8plus.g_upper[i]);
+ err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
+ &sf->v8plus.asi);
+
+ if (psr & PSR_EF) {
+ __siginfo_fpu_t __user *fp = tail;
+ tail += sizeof(*fp);
+ err |= save_fpu_state(regs, fp);
+ err |= __put_user((u64)fp, &sf->fpu_save);
+ } else {
+ err |= __put_user(0, &sf->fpu_save);
+ }
+ if (wsaved) {
+ __siginfo_rwin_t __user *rwp = tail;
+ tail += sizeof(*rwp);
+ err |= save_rwin_state(wsaved, rwp);
+ err |= __put_user((u64)rwp, &sf->rwin_save);
+ set_thread_wsaved(0);
+ } else {
+ err |= __put_user(0, &sf->rwin_save);
+ }
+
+ /* If these change we need to know - assignments to seta relies on these sizes */
+ BUILD_BUG_ON(_NSIG_WORDS != 1);
+ BUILD_BUG_ON(_COMPAT_NSIG_WORDS != 2);
+ seta.sig[1] = (oldset->sig[0] >> 32);
+ seta.sig[0] = oldset->sig[0];
+
+ err |= __put_user(seta.sig[0], &sf->info.si_mask);
+ err |= __copy_to_user(sf->extramask, &seta.sig[1],
+ (_COMPAT_NSIG_WORDS - 1) * sizeof(unsigned int));
+
+ if (!wsaved) {
+ err |= raw_copy_in_user((u32 __user *)sf,
+ (u32 __user *)(regs->u_regs[UREG_FP]),
+ sizeof(struct reg_window32));
+ } else {
+ struct reg_window *rp;
+
+ rp = &current_thread_info()->reg_window[wsaved - 1];
+ for (i = 0; i < 8; i++)
+ err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
+ for (i = 0; i < 6; i++)
+ err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
+ err |= __put_user(rp->ins[6], &sf->ss.fp);
+ err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
+ }
+ if (err)
+ return err;
+
+ /* 3. signal handler back-trampoline and parameters */
+ regs->u_regs[UREG_FP] = (unsigned long) sf;
+ regs->u_regs[UREG_I0] = ksig->sig;
+ regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
+ regs->u_regs[UREG_I2] = (unsigned long) &sf->info;
+
+ /* 4. signal handler */
+ regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
+ regs->tnpc = (regs->tpc + 4);
+ if (test_thread_flag(TIF_32BIT)) {
+ regs->tpc &= 0xffffffff;
+ regs->tnpc &= 0xffffffff;
+ }
+
+ /* 5. return to kernel instructions */
+ if (ksig->ka.ka_restorer) {
+ regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
+ } else {
+ unsigned long address = ((unsigned long)&(sf->insns[0]));
+
+ regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
+
+ err = __put_user(0x821020d8, &sf->insns[0]); /*mov __NR_sigreturn, %g1*/
+ err |= __put_user(0x91d02010, &sf->insns[1]); /*t 0x10*/
+ if (err)
+ return err;
+ flush_signal_insns(address);
+ }
+ return 0;
+}
+
+static int setup_rt_frame32(struct ksignal *ksig, struct pt_regs *regs,
+ sigset_t *oldset)
+{
+ struct rt_signal_frame32 __user *sf;
+ int i, err, wsaved;
+ void __user *tail;
+ int sigframe_size;
+ u32 psr;
+
+ /* 1. Make sure everything is clean */
+ synchronize_user_stack();
+ save_and_clear_fpu();
+
+ wsaved = get_thread_wsaved();
+
+ sigframe_size = sizeof(*sf);
+ if (current_thread_info()->fpsaved[0] & FPRS_FEF)
+ sigframe_size += sizeof(__siginfo_fpu_t);
+ if (wsaved)
+ sigframe_size += sizeof(__siginfo_rwin_t);
+
+ sf = (struct rt_signal_frame32 __user *)
+ get_sigframe(ksig, regs, sigframe_size);
+
+ if (invalid_frame_pointer(sf, sigframe_size)) {
+ if (show_unhandled_signals)
+ pr_info("%s[%d] bad frame in setup_rt_frame32: %08lx TPC %08lx O7 %08lx\n",
+ current->comm, current->pid, (unsigned long)sf,
+ regs->tpc, regs->u_regs[UREG_I7]);
+ force_sigsegv(ksig->sig);
+ return -EINVAL;
+ }
+
+ tail = (sf + 1);
+
+ /* 2. Save the current process state */
+ if (test_thread_flag(TIF_32BIT)) {
+ regs->tpc &= 0xffffffff;
+ regs->tnpc &= 0xffffffff;
+ }
+ err = put_user(regs->tpc, &sf->regs.pc);
+ err |= __put_user(regs->tnpc, &sf->regs.npc);
+ err |= __put_user(regs->y, &sf->regs.y);
+ psr = tstate_to_psr(regs->tstate);
+ if (current_thread_info()->fpsaved[0] & FPRS_FEF)
+ psr |= PSR_EF;
+ err |= __put_user(psr, &sf->regs.psr);
+ for (i = 0; i < 16; i++)
+ err |= __put_user(regs->u_regs[i], &sf->regs.u_regs[i]);
+ err |= __put_user(sizeof(siginfo_extra_v8plus_t), &sf->extra_size);
+ err |= __put_user(SIGINFO_EXTRA_V8PLUS_MAGIC, &sf->v8plus.g_upper[0]);
+ for (i = 1; i < 16; i++)
+ err |= __put_user(((u32 *)regs->u_regs)[2*i],
+ &sf->v8plus.g_upper[i]);
+ err |= __put_user((regs->tstate & TSTATE_ASI) >> 24UL,
+ &sf->v8plus.asi);
+
+ if (psr & PSR_EF) {
+ __siginfo_fpu_t __user *fp = tail;
+ tail += sizeof(*fp);
+ err |= save_fpu_state(regs, fp);
+ err |= __put_user((u64)fp, &sf->fpu_save);
+ } else {
+ err |= __put_user(0, &sf->fpu_save);
+ }
+ if (wsaved) {
+ __siginfo_rwin_t __user *rwp = tail;
+ tail += sizeof(*rwp);
+ err |= save_rwin_state(wsaved, rwp);
+ err |= __put_user((u64)rwp, &sf->rwin_save);
+ set_thread_wsaved(0);
+ } else {
+ err |= __put_user(0, &sf->rwin_save);
+ }
+
+ /* Update the siginfo structure. */
+ err |= copy_siginfo_to_user32(&sf->info, &ksig->info);
+
+ /* Setup sigaltstack */
+ err |= __compat_save_altstack(&sf->stack, regs->u_regs[UREG_FP]);
+
+ err |= put_compat_sigset(&sf->mask, oldset, sizeof(compat_sigset_t));
+
+ if (!wsaved) {
+ err |= raw_copy_in_user((u32 __user *)sf,
+ (u32 __user *)(regs->u_regs[UREG_FP]),
+ sizeof(struct reg_window32));
+ } else {
+ struct reg_window *rp;
+
+ rp = &current_thread_info()->reg_window[wsaved - 1];
+ for (i = 0; i < 8; i++)
+ err |= __put_user(rp->locals[i], &sf->ss.locals[i]);
+ for (i = 0; i < 6; i++)
+ err |= __put_user(rp->ins[i], &sf->ss.ins[i]);
+ err |= __put_user(rp->ins[6], &sf->ss.fp);
+ err |= __put_user(rp->ins[7], &sf->ss.callers_pc);
+ }
+ if (err)
+ return err;
+
+ /* 3. signal handler back-trampoline and parameters */
+ regs->u_regs[UREG_FP] = (unsigned long) sf;
+ regs->u_regs[UREG_I0] = ksig->sig;
+ regs->u_regs[UREG_I1] = (unsigned long) &sf->info;
+ regs->u_regs[UREG_I2] = (unsigned long) &sf->regs;
+
+ /* 4. signal handler */
+ regs->tpc = (unsigned long) ksig->ka.sa.sa_handler;
+ regs->tnpc = (regs->tpc + 4);
+ if (test_thread_flag(TIF_32BIT)) {
+ regs->tpc &= 0xffffffff;
+ regs->tnpc &= 0xffffffff;
+ }
+
+ /* 5. return to kernel instructions */
+ if (ksig->ka.ka_restorer)
+ regs->u_regs[UREG_I7] = (unsigned long)ksig->ka.ka_restorer;
+ else {
+ unsigned long address = ((unsigned long)&(sf->insns[0]));
+
+ regs->u_regs[UREG_I7] = (unsigned long) (&(sf->insns[0]) - 2);
+
+ /* mov __NR_rt_sigreturn, %g1 */
+ err |= __put_user(0x82102065, &sf->insns[0]);
+
+ /* t 0x10 */
+ err |= __put_user(0x91d02010, &sf->insns[1]);
+ if (err)
+ return err;
+
+ flush_signal_insns(address);
+ }
+ return 0;
+}
+
+static inline void handle_signal32(struct ksignal *ksig,
+ struct pt_regs *regs)
+{
+ sigset_t *oldset = sigmask_to_save();
+ int err;
+
+ if (ksig->ka.sa.sa_flags & SA_SIGINFO)
+ err = setup_rt_frame32(ksig, regs, oldset);
+ else
+ err = setup_frame32(ksig, regs, oldset);
+
+ signal_setup_done(err, ksig, 0);
+}
+
+static inline void syscall_restart32(unsigned long orig_i0, struct pt_regs *regs,
+ struct sigaction *sa)
+{
+ switch (regs->u_regs[UREG_I0]) {
+ case ERESTART_RESTARTBLOCK:
+ case ERESTARTNOHAND:
+ no_system_call_restart:
+ regs->u_regs[UREG_I0] = EINTR;
+ regs->tstate |= TSTATE_ICARRY;
+ break;
+ case ERESTARTSYS:
+ if (!(sa->sa_flags & SA_RESTART))
+ goto no_system_call_restart;
+ fallthrough;
+ case ERESTARTNOINTR:
+ regs->u_regs[UREG_I0] = orig_i0;
+ regs->tpc -= 4;
+ regs->tnpc -= 4;
+ }
+}
+
+/* Note that 'init' is a special process: it doesn't get signals it doesn't
+ * want to handle. Thus you cannot kill init even with a SIGKILL even by
+ * mistake.
+ */
+void do_signal32(struct pt_regs * regs)
+{
+ struct ksignal ksig;
+ unsigned long orig_i0 = 0;
+ int restart_syscall = 0;
+ bool has_handler = get_signal(&ksig);
+
+ if (pt_regs_is_syscall(regs) &&
+ (regs->tstate & (TSTATE_XCARRY | TSTATE_ICARRY))) {
+ restart_syscall = 1;
+ orig_i0 = regs->u_regs[UREG_G6];
+ }
+
+ if (has_handler) {
+ if (restart_syscall)
+ syscall_restart32(orig_i0, regs, &ksig.ka.sa);
+ handle_signal32(&ksig, regs);
+ } else {
+ if (restart_syscall) {
+ switch (regs->u_regs[UREG_I0]) {
+ case ERESTARTNOHAND:
+ case ERESTARTSYS:
+ case ERESTARTNOINTR:
+ /* replay the system call when we are done */
+ regs->u_regs[UREG_I0] = orig_i0;
+ regs->tpc -= 4;
+ regs->tnpc -= 4;
+ pt_regs_clear_syscall(regs);
+ fallthrough;
+ case ERESTART_RESTARTBLOCK:
+ regs->u_regs[UREG_G1] = __NR_restart_syscall;
+ regs->tpc -= 4;
+ regs->tnpc -= 4;
+ pt_regs_clear_syscall(regs);
+ }
+ }
+ restore_saved_sigmask();
+ }
+}
+
+struct sigstack32 {
+ u32 the_stack;
+ int cur_status;
+};
+
+asmlinkage int do_sys32_sigstack(u32 u_ssptr, u32 u_ossptr, unsigned long sp)
+{
+ struct sigstack32 __user *ssptr =
+ (struct sigstack32 __user *)((unsigned long)(u_ssptr));
+ struct sigstack32 __user *ossptr =
+ (struct sigstack32 __user *)((unsigned long)(u_ossptr));
+ int ret = -EFAULT;
+
+ /* First see if old state is wanted. */
+ if (ossptr) {
+ if (put_user(current->sas_ss_sp + current->sas_ss_size,
+ &ossptr->the_stack) ||
+ __put_user(on_sig_stack(sp), &ossptr->cur_status))
+ goto out;
+ }
+
+ /* Now see if we want to update the new state. */
+ if (ssptr) {
+ u32 ss_sp;
+
+ if (get_user(ss_sp, &ssptr->the_stack))
+ goto out;
+
+ /* If the current stack was set with sigaltstack, don't
+ * swap stacks while we are on it.
+ */
+ ret = -EPERM;
+ if (current->sas_ss_sp && on_sig_stack(sp))
+ goto out;
+
+ /* Since we don't know the extent of the stack, and we don't
+ * track onstack-ness, but rather calculate it, we must
+ * presume a size. Ho hum this interface is lossy.
+ */
+ current->sas_ss_sp = (unsigned long)ss_sp - SIGSTKSZ;
+ current->sas_ss_size = SIGSTKSZ;
+ }
+
+ ret = 0;
+out:
+ return ret;
+}
+
+/*
+ * Compile-time assertions for siginfo_t offsets. Check NSIG* as well, as
+ * changes likely come with new fields that should be added below.
+ */
+static_assert(NSIGILL == 11);
+static_assert(NSIGFPE == 15);
+static_assert(NSIGSEGV == 10);
+static_assert(NSIGBUS == 5);
+static_assert(NSIGTRAP == 6);
+static_assert(NSIGCHLD == 6);
+static_assert(NSIGSYS == 2);
+static_assert(sizeof(compat_siginfo_t) == 128);
+static_assert(__alignof__(compat_siginfo_t) == 4);
+static_assert(offsetof(compat_siginfo_t, si_signo) == 0x00);
+static_assert(offsetof(compat_siginfo_t, si_errno) == 0x04);
+static_assert(offsetof(compat_siginfo_t, si_code) == 0x08);
+static_assert(offsetof(compat_siginfo_t, si_pid) == 0x0c);
+static_assert(offsetof(compat_siginfo_t, si_uid) == 0x10);
+static_assert(offsetof(compat_siginfo_t, si_tid) == 0x0c);
+static_assert(offsetof(compat_siginfo_t, si_overrun) == 0x10);
+static_assert(offsetof(compat_siginfo_t, si_status) == 0x14);
+static_assert(offsetof(compat_siginfo_t, si_utime) == 0x18);
+static_assert(offsetof(compat_siginfo_t, si_stime) == 0x1c);
+static_assert(offsetof(compat_siginfo_t, si_value) == 0x14);
+static_assert(offsetof(compat_siginfo_t, si_int) == 0x14);
+static_assert(offsetof(compat_siginfo_t, si_ptr) == 0x14);
+static_assert(offsetof(compat_siginfo_t, si_addr) == 0x0c);
+static_assert(offsetof(compat_siginfo_t, si_trapno) == 0x10);
+static_assert(offsetof(compat_siginfo_t, si_addr_lsb) == 0x10);
+static_assert(offsetof(compat_siginfo_t, si_lower) == 0x14);
+static_assert(offsetof(compat_siginfo_t, si_upper) == 0x18);
+static_assert(offsetof(compat_siginfo_t, si_pkey) == 0x14);
+static_assert(offsetof(compat_siginfo_t, si_perf_data) == 0x10);
+static_assert(offsetof(compat_siginfo_t, si_perf_type) == 0x14);
+static_assert(offsetof(compat_siginfo_t, si_perf_flags) == 0x18);
+static_assert(offsetof(compat_siginfo_t, si_band) == 0x0c);
+static_assert(offsetof(compat_siginfo_t, si_fd) == 0x10);