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-rw-r--r--linux-user/i386/signal.c584
1 files changed, 584 insertions, 0 deletions
diff --git a/linux-user/i386/signal.c b/linux-user/i386/signal.c
index 02ca338b6c..4a190e6435 100644
--- a/linux-user/i386/signal.c
+++ b/linux-user/i386/signal.c
@@ -16,3 +16,587 @@
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
+#include "qemu/osdep.h"
+#include "qemu.h"
+#include "target_signal.h"
+#include "signal-common.h"
+#include "linux-user/trace.h"
+
+/* from the Linux kernel - /arch/x86/include/uapi/asm/sigcontext.h */
+
+struct target_fpreg {
+ uint16_t significand[4];
+ uint16_t exponent;
+};
+
+struct target_fpxreg {
+ uint16_t significand[4];
+ uint16_t exponent;
+ uint16_t padding[3];
+};
+
+struct target_xmmreg {
+ uint32_t element[4];
+};
+
+struct target_fpstate_32 {
+ /* Regular FPU environment */
+ uint32_t cw;
+ uint32_t sw;
+ uint32_t tag;
+ uint32_t ipoff;
+ uint32_t cssel;
+ uint32_t dataoff;
+ uint32_t datasel;
+ struct target_fpreg st[8];
+ uint16_t status;
+ uint16_t magic; /* 0xffff = regular FPU data only */
+
+ /* FXSR FPU environment */
+ uint32_t _fxsr_env[6]; /* FXSR FPU env is ignored */
+ uint32_t mxcsr;
+ uint32_t reserved;
+ struct target_fpxreg fxsr_st[8]; /* FXSR FPU reg data is ignored */
+ struct target_xmmreg xmm[8];
+ uint32_t padding[56];
+};
+
+struct target_fpstate_64 {
+ /* FXSAVE format */
+ uint16_t cw;
+ uint16_t sw;
+ uint16_t twd;
+ uint16_t fop;
+ uint64_t rip;
+ uint64_t rdp;
+ uint32_t mxcsr;
+ uint32_t mxcsr_mask;
+ uint32_t st_space[32];
+ uint32_t xmm_space[64];
+ uint32_t reserved[24];
+};
+
+#ifndef TARGET_X86_64
+# define target_fpstate target_fpstate_32
+#else
+# define target_fpstate target_fpstate_64
+#endif
+
+struct target_sigcontext_32 {
+ uint16_t gs, __gsh;
+ uint16_t fs, __fsh;
+ uint16_t es, __esh;
+ uint16_t ds, __dsh;
+ uint32_t edi;
+ uint32_t esi;
+ uint32_t ebp;
+ uint32_t esp;
+ uint32_t ebx;
+ uint32_t edx;
+ uint32_t ecx;
+ uint32_t eax;
+ uint32_t trapno;
+ uint32_t err;
+ uint32_t eip;
+ uint16_t cs, __csh;
+ uint32_t eflags;
+ uint32_t esp_at_signal;
+ uint16_t ss, __ssh;
+ uint32_t fpstate; /* pointer */
+ uint32_t oldmask;
+ uint32_t cr2;
+};
+
+struct target_sigcontext_64 {
+ uint64_t r8;
+ uint64_t r9;
+ uint64_t r10;
+ uint64_t r11;
+ uint64_t r12;
+ uint64_t r13;
+ uint64_t r14;
+ uint64_t r15;
+
+ uint64_t rdi;
+ uint64_t rsi;
+ uint64_t rbp;
+ uint64_t rbx;
+ uint64_t rdx;
+ uint64_t rax;
+ uint64_t rcx;
+ uint64_t rsp;
+ uint64_t rip;
+
+ uint64_t eflags;
+
+ uint16_t cs;
+ uint16_t gs;
+ uint16_t fs;
+ uint16_t ss;
+
+ uint64_t err;
+ uint64_t trapno;
+ uint64_t oldmask;
+ uint64_t cr2;
+
+ uint64_t fpstate; /* pointer */
+ uint64_t padding[8];
+};
+
+#ifndef TARGET_X86_64
+# define target_sigcontext target_sigcontext_32
+#else
+# define target_sigcontext target_sigcontext_64
+#endif
+
+/* see Linux/include/uapi/asm-generic/ucontext.h */
+struct target_ucontext {
+ abi_ulong tuc_flags;
+ abi_ulong tuc_link;
+ target_stack_t tuc_stack;
+ struct target_sigcontext tuc_mcontext;
+ target_sigset_t tuc_sigmask; /* mask last for extensibility */
+};
+
+#ifndef TARGET_X86_64
+struct sigframe {
+ abi_ulong pretcode;
+ int sig;
+ struct target_sigcontext sc;
+ struct target_fpstate fpstate;
+ abi_ulong extramask[TARGET_NSIG_WORDS-1];
+ char retcode[8];
+};
+
+struct rt_sigframe {
+ abi_ulong pretcode;
+ int sig;
+ abi_ulong pinfo;
+ abi_ulong puc;
+ struct target_siginfo info;
+ struct target_ucontext uc;
+ struct target_fpstate fpstate;
+ char retcode[8];
+};
+
+#else
+
+struct rt_sigframe {
+ abi_ulong pretcode;
+ struct target_ucontext uc;
+ struct target_siginfo info;
+ struct target_fpstate fpstate;
+};
+
+#endif
+
+/*
+ * Set up a signal frame.
+ */
+
+/* XXX: save x87 state */
+static void setup_sigcontext(struct target_sigcontext *sc,
+ struct target_fpstate *fpstate, CPUX86State *env, abi_ulong mask,
+ abi_ulong fpstate_addr)
+{
+ CPUState *cs = CPU(x86_env_get_cpu(env));
+#ifndef TARGET_X86_64
+ uint16_t magic;
+
+ /* already locked in setup_frame() */
+ __put_user(env->segs[R_GS].selector, (unsigned int *)&sc->gs);
+ __put_user(env->segs[R_FS].selector, (unsigned int *)&sc->fs);
+ __put_user(env->segs[R_ES].selector, (unsigned int *)&sc->es);
+ __put_user(env->segs[R_DS].selector, (unsigned int *)&sc->ds);
+ __put_user(env->regs[R_EDI], &sc->edi);
+ __put_user(env->regs[R_ESI], &sc->esi);
+ __put_user(env->regs[R_EBP], &sc->ebp);
+ __put_user(env->regs[R_ESP], &sc->esp);
+ __put_user(env->regs[R_EBX], &sc->ebx);
+ __put_user(env->regs[R_EDX], &sc->edx);
+ __put_user(env->regs[R_ECX], &sc->ecx);
+ __put_user(env->regs[R_EAX], &sc->eax);
+ __put_user(cs->exception_index, &sc->trapno);
+ __put_user(env->error_code, &sc->err);
+ __put_user(env->eip, &sc->eip);
+ __put_user(env->segs[R_CS].selector, (unsigned int *)&sc->cs);
+ __put_user(env->eflags, &sc->eflags);
+ __put_user(env->regs[R_ESP], &sc->esp_at_signal);
+ __put_user(env->segs[R_SS].selector, (unsigned int *)&sc->ss);
+
+ cpu_x86_fsave(env, fpstate_addr, 1);
+ fpstate->status = fpstate->sw;
+ magic = 0xffff;
+ __put_user(magic, &fpstate->magic);
+ __put_user(fpstate_addr, &sc->fpstate);
+
+ /* non-iBCS2 extensions.. */
+ __put_user(mask, &sc->oldmask);
+ __put_user(env->cr[2], &sc->cr2);
+#else
+ __put_user(env->regs[R_EDI], &sc->rdi);
+ __put_user(env->regs[R_ESI], &sc->rsi);
+ __put_user(env->regs[R_EBP], &sc->rbp);
+ __put_user(env->regs[R_ESP], &sc->rsp);
+ __put_user(env->regs[R_EBX], &sc->rbx);
+ __put_user(env->regs[R_EDX], &sc->rdx);
+ __put_user(env->regs[R_ECX], &sc->rcx);
+ __put_user(env->regs[R_EAX], &sc->rax);
+
+ __put_user(env->regs[8], &sc->r8);
+ __put_user(env->regs[9], &sc->r9);
+ __put_user(env->regs[10], &sc->r10);
+ __put_user(env->regs[11], &sc->r11);
+ __put_user(env->regs[12], &sc->r12);
+ __put_user(env->regs[13], &sc->r13);
+ __put_user(env->regs[14], &sc->r14);
+ __put_user(env->regs[15], &sc->r15);
+
+ __put_user(cs->exception_index, &sc->trapno);
+ __put_user(env->error_code, &sc->err);
+ __put_user(env->eip, &sc->rip);
+
+ __put_user(env->eflags, &sc->eflags);
+ __put_user(env->segs[R_CS].selector, &sc->cs);
+ __put_user((uint16_t)0, &sc->gs);
+ __put_user((uint16_t)0, &sc->fs);
+ __put_user(env->segs[R_SS].selector, &sc->ss);
+
+ __put_user(mask, &sc->oldmask);
+ __put_user(env->cr[2], &sc->cr2);
+
+ /* fpstate_addr must be 16 byte aligned for fxsave */
+ assert(!(fpstate_addr & 0xf));
+
+ cpu_x86_fxsave(env, fpstate_addr);
+ __put_user(fpstate_addr, &sc->fpstate);
+#endif
+}
+
+/*
+ * Determine which stack to use..
+ */
+
+static inline abi_ulong
+get_sigframe(struct target_sigaction *ka, CPUX86State *env, size_t frame_size)
+{
+ unsigned long esp;
+
+ /* Default to using normal stack */
+ esp = env->regs[R_ESP];
+#ifdef TARGET_X86_64
+ esp -= 128; /* this is the redzone */
+#endif
+
+ /* This is the X/Open sanctioned signal stack switching. */
+ if (ka->sa_flags & TARGET_SA_ONSTACK) {
+ if (sas_ss_flags(esp) == 0) {
+ esp = target_sigaltstack_used.ss_sp + target_sigaltstack_used.ss_size;
+ }
+ } else {
+#ifndef TARGET_X86_64
+ /* This is the legacy signal stack switching. */
+ if ((env->segs[R_SS].selector & 0xffff) != __USER_DS &&
+ !(ka->sa_flags & TARGET_SA_RESTORER) &&
+ ka->sa_restorer) {
+ esp = (unsigned long) ka->sa_restorer;
+ }
+#endif
+ }
+
+#ifndef TARGET_X86_64
+ return (esp - frame_size) & -8ul;
+#else
+ return ((esp - frame_size) & (~15ul)) - 8;
+#endif
+}
+
+#ifndef TARGET_X86_64
+/* compare linux/arch/i386/kernel/signal.c:setup_frame() */
+void setup_frame(int sig, struct target_sigaction *ka,
+ target_sigset_t *set, CPUX86State *env)
+{
+ abi_ulong frame_addr;
+ struct sigframe *frame;
+ int i;
+
+ frame_addr = get_sigframe(ka, env, sizeof(*frame));
+ trace_user_setup_frame(env, frame_addr);
+
+ if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
+ goto give_sigsegv;
+
+ __put_user(sig, &frame->sig);
+
+ setup_sigcontext(&frame->sc, &frame->fpstate, env, set->sig[0],
+ frame_addr + offsetof(struct sigframe, fpstate));
+
+ for(i = 1; i < TARGET_NSIG_WORDS; i++) {
+ __put_user(set->sig[i], &frame->extramask[i - 1]);
+ }
+
+ /* Set up to return from userspace. If provided, use a stub
+ already in userspace. */
+ if (ka->sa_flags & TARGET_SA_RESTORER) {
+ __put_user(ka->sa_restorer, &frame->pretcode);
+ } else {
+ uint16_t val16;
+ abi_ulong retcode_addr;
+ retcode_addr = frame_addr + offsetof(struct sigframe, retcode);
+ __put_user(retcode_addr, &frame->pretcode);
+ /* This is popl %eax ; movl $,%eax ; int $0x80 */
+ val16 = 0xb858;
+ __put_user(val16, (uint16_t *)(frame->retcode+0));
+ __put_user(TARGET_NR_sigreturn, (int *)(frame->retcode+2));
+ val16 = 0x80cd;
+ __put_user(val16, (uint16_t *)(frame->retcode+6));
+ }
+
+ /* Set up registers for signal handler */
+ env->regs[R_ESP] = frame_addr;
+ env->eip = ka->_sa_handler;
+
+ cpu_x86_load_seg(env, R_DS, __USER_DS);
+ cpu_x86_load_seg(env, R_ES, __USER_DS);
+ cpu_x86_load_seg(env, R_SS, __USER_DS);
+ cpu_x86_load_seg(env, R_CS, __USER_CS);
+ env->eflags &= ~TF_MASK;
+
+ unlock_user_struct(frame, frame_addr, 1);
+
+ return;
+
+give_sigsegv:
+ force_sigsegv(sig);
+}
+#endif
+
+/* compare linux/arch/x86/kernel/signal.c:setup_rt_frame() */
+void setup_rt_frame(int sig, struct target_sigaction *ka,
+ target_siginfo_t *info,
+ target_sigset_t *set, CPUX86State *env)
+{
+ abi_ulong frame_addr;
+#ifndef TARGET_X86_64
+ abi_ulong addr;
+#endif
+ struct rt_sigframe *frame;
+ int i;
+
+ frame_addr = get_sigframe(ka, env, sizeof(*frame));
+ trace_user_setup_rt_frame(env, frame_addr);
+
+ if (!lock_user_struct(VERIFY_WRITE, frame, frame_addr, 0))
+ goto give_sigsegv;
+
+ /* These fields are only in rt_sigframe on 32 bit */
+#ifndef TARGET_X86_64
+ __put_user(sig, &frame->sig);
+ addr = frame_addr + offsetof(struct rt_sigframe, info);
+ __put_user(addr, &frame->pinfo);
+ addr = frame_addr + offsetof(struct rt_sigframe, uc);
+ __put_user(addr, &frame->puc);
+#endif
+ if (ka->sa_flags & TARGET_SA_SIGINFO) {
+ tswap_siginfo(&frame->info, info);
+ }
+
+ /* Create the ucontext. */
+ __put_user(0, &frame->uc.tuc_flags);
+ __put_user(0, &frame->uc.tuc_link);
+ __put_user(target_sigaltstack_used.ss_sp, &frame->uc.tuc_stack.ss_sp);
+ __put_user(sas_ss_flags(get_sp_from_cpustate(env)),
+ &frame->uc.tuc_stack.ss_flags);
+ __put_user(target_sigaltstack_used.ss_size,
+ &frame->uc.tuc_stack.ss_size);
+ setup_sigcontext(&frame->uc.tuc_mcontext, &frame->fpstate, env,
+ set->sig[0], frame_addr + offsetof(struct rt_sigframe, fpstate));
+
+ for(i = 0; i < TARGET_NSIG_WORDS; i++) {
+ __put_user(set->sig[i], &frame->uc.tuc_sigmask.sig[i]);
+ }
+
+ /* Set up to return from userspace. If provided, use a stub
+ already in userspace. */
+#ifndef TARGET_X86_64
+ if (ka->sa_flags & TARGET_SA_RESTORER) {
+ __put_user(ka->sa_restorer, &frame->pretcode);
+ } else {
+ uint16_t val16;
+ addr = frame_addr + offsetof(struct rt_sigframe, retcode);
+ __put_user(addr, &frame->pretcode);
+ /* This is movl $,%eax ; int $0x80 */
+ __put_user(0xb8, (char *)(frame->retcode+0));
+ __put_user(TARGET_NR_rt_sigreturn, (int *)(frame->retcode+1));
+ val16 = 0x80cd;
+ __put_user(val16, (uint16_t *)(frame->retcode+5));
+ }
+#else
+ /* XXX: Would be slightly better to return -EFAULT here if test fails
+ assert(ka->sa_flags & TARGET_SA_RESTORER); */
+ __put_user(ka->sa_restorer, &frame->pretcode);
+#endif
+
+ /* Set up registers for signal handler */
+ env->regs[R_ESP] = frame_addr;
+ env->eip = ka->_sa_handler;
+
+#ifndef TARGET_X86_64
+ env->regs[R_EAX] = sig;
+ env->regs[R_EDX] = (unsigned long)&frame->info;
+ env->regs[R_ECX] = (unsigned long)&frame->uc;
+#else
+ env->regs[R_EAX] = 0;
+ env->regs[R_EDI] = sig;
+ env->regs[R_ESI] = (unsigned long)&frame->info;
+ env->regs[R_EDX] = (unsigned long)&frame->uc;
+#endif
+
+ cpu_x86_load_seg(env, R_DS, __USER_DS);
+ cpu_x86_load_seg(env, R_ES, __USER_DS);
+ cpu_x86_load_seg(env, R_CS, __USER_CS);
+ cpu_x86_load_seg(env, R_SS, __USER_DS);
+ env->eflags &= ~TF_MASK;
+
+ unlock_user_struct(frame, frame_addr, 1);
+
+ return;
+
+give_sigsegv:
+ force_sigsegv(sig);
+}
+
+static int
+restore_sigcontext(CPUX86State *env, struct target_sigcontext *sc)
+{
+ unsigned int err = 0;
+ abi_ulong fpstate_addr;
+ unsigned int tmpflags;
+
+#ifndef TARGET_X86_64
+ cpu_x86_load_seg(env, R_GS, tswap16(sc->gs));
+ cpu_x86_load_seg(env, R_FS, tswap16(sc->fs));
+ cpu_x86_load_seg(env, R_ES, tswap16(sc->es));
+ cpu_x86_load_seg(env, R_DS, tswap16(sc->ds));
+
+ env->regs[R_EDI] = tswapl(sc->edi);
+ env->regs[R_ESI] = tswapl(sc->esi);
+ env->regs[R_EBP] = tswapl(sc->ebp);
+ env->regs[R_ESP] = tswapl(sc->esp);
+ env->regs[R_EBX] = tswapl(sc->ebx);
+ env->regs[R_EDX] = tswapl(sc->edx);
+ env->regs[R_ECX] = tswapl(sc->ecx);
+ env->regs[R_EAX] = tswapl(sc->eax);
+
+ env->eip = tswapl(sc->eip);
+#else
+ env->regs[8] = tswapl(sc->r8);
+ env->regs[9] = tswapl(sc->r9);
+ env->regs[10] = tswapl(sc->r10);
+ env->regs[11] = tswapl(sc->r11);
+ env->regs[12] = tswapl(sc->r12);
+ env->regs[13] = tswapl(sc->r13);
+ env->regs[14] = tswapl(sc->r14);
+ env->regs[15] = tswapl(sc->r15);
+
+ env->regs[R_EDI] = tswapl(sc->rdi);
+ env->regs[R_ESI] = tswapl(sc->rsi);
+ env->regs[R_EBP] = tswapl(sc->rbp);
+ env->regs[R_EBX] = tswapl(sc->rbx);
+ env->regs[R_EDX] = tswapl(sc->rdx);
+ env->regs[R_EAX] = tswapl(sc->rax);
+ env->regs[R_ECX] = tswapl(sc->rcx);
+ env->regs[R_ESP] = tswapl(sc->rsp);
+
+ env->eip = tswapl(sc->rip);
+#endif
+
+ cpu_x86_load_seg(env, R_CS, lduw_p(&sc->cs) | 3);
+ cpu_x86_load_seg(env, R_SS, lduw_p(&sc->ss) | 3);
+
+ tmpflags = tswapl(sc->eflags);
+ env->eflags = (env->eflags & ~0x40DD5) | (tmpflags & 0x40DD5);
+ // regs->orig_eax = -1; /* disable syscall checks */
+
+ fpstate_addr = tswapl(sc->fpstate);
+ if (fpstate_addr != 0) {
+ if (!access_ok(VERIFY_READ, fpstate_addr,
+ sizeof(struct target_fpstate)))
+ goto badframe;
+#ifndef TARGET_X86_64
+ cpu_x86_frstor(env, fpstate_addr, 1);
+#else
+ cpu_x86_fxrstor(env, fpstate_addr);
+#endif
+ }
+
+ return err;
+badframe:
+ return 1;
+}
+
+/* Note: there is no sigreturn on x86_64, there is only rt_sigreturn */
+#ifndef TARGET_X86_64
+long do_sigreturn(CPUX86State *env)
+{
+ struct sigframe *frame;
+ abi_ulong frame_addr = env->regs[R_ESP] - 8;
+ target_sigset_t target_set;
+ sigset_t set;
+ int i;
+
+ trace_user_do_sigreturn(env, frame_addr);
+ if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
+ goto badframe;
+ /* set blocked signals */
+ __get_user(target_set.sig[0], &frame->sc.oldmask);
+ for(i = 1; i < TARGET_NSIG_WORDS; i++) {
+ __get_user(target_set.sig[i], &frame->extramask[i - 1]);
+ }
+
+ target_to_host_sigset_internal(&set, &target_set);
+ set_sigmask(&set);
+
+ /* restore registers */
+ if (restore_sigcontext(env, &frame->sc))
+ goto badframe;
+ unlock_user_struct(frame, frame_addr, 0);
+ return -TARGET_QEMU_ESIGRETURN;
+
+badframe:
+ unlock_user_struct(frame, frame_addr, 0);
+ force_sig(TARGET_SIGSEGV);
+ return -TARGET_QEMU_ESIGRETURN;
+}
+#endif
+
+long do_rt_sigreturn(CPUX86State *env)
+{
+ abi_ulong frame_addr;
+ struct rt_sigframe *frame;
+ sigset_t set;
+
+ frame_addr = env->regs[R_ESP] - sizeof(abi_ulong);
+ trace_user_do_rt_sigreturn(env, frame_addr);
+ if (!lock_user_struct(VERIFY_READ, frame, frame_addr, 1))
+ goto badframe;
+ target_to_host_sigset(&set, &frame->uc.tuc_sigmask);
+ set_sigmask(&set);
+
+ if (restore_sigcontext(env, &frame->uc.tuc_mcontext)) {
+ goto badframe;
+ }
+
+ if (do_sigaltstack(frame_addr + offsetof(struct rt_sigframe, uc.tuc_stack), 0,
+ get_sp_from_cpustate(env)) == -EFAULT) {
+ goto badframe;
+ }
+
+ unlock_user_struct(frame, frame_addr, 0);
+ return -TARGET_QEMU_ESIGRETURN;
+
+badframe:
+ unlock_user_struct(frame, frame_addr, 0);
+ force_sig(TARGET_SIGSEGV);
+ return -TARGET_QEMU_ESIGRETURN;
+}
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-24 11:30:49 +0000