x32: Signal-related system calls

x32 uses the 64-bit signal frame format, obviously, but there are some
structures which mixes that with pointers or sizeof(long) types, as
such we have to create a handful of system calls specific to x32.  By
and large these are a mixture of the 64-bit and the compat system
calls.

Originally-by: H. J. Lu <hjl.tools@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
This commit is contained in:
H. Peter Anvin 2012-02-19 09:41:09 -08:00
parent a96d692e9a
commit c5a373942b
2 changed files with 136 additions and 1 deletions

View File

@ -746,6 +746,25 @@ ENTRY(stub_rt_sigreturn)
CFI_ENDPROC
END(stub_rt_sigreturn)
#ifdef CONFIG_X86_X32_ABI
PTREGSCALL stub_x32_sigaltstack, sys32_sigaltstack, %rdx
ENTRY(stub_x32_rt_sigreturn)
CFI_STARTPROC
addq $8, %rsp
PARTIAL_FRAME 0
SAVE_REST
movq %rsp,%rdi
FIXUP_TOP_OF_STACK %r11
call sys32_x32_rt_sigreturn
movq %rax,RAX(%rsp) # fixme, this could be done at the higher layer
RESTORE_REST
jmp int_ret_from_sys_call
CFI_ENDPROC
END(stub_x32_rt_sigreturn)
#endif
/*
* Build the entry stubs and pointer table with some assembler magic.
* We pack 7 stubs into a single 32-byte chunk, which will fit in a

View File

@ -29,6 +29,7 @@
#ifdef CONFIG_X86_64
#include <asm/proto.h>
#include <asm/ia32_unistd.h>
#include <asm/sys_ia32.h>
#endif /* CONFIG_X86_64 */
#include <asm/syscall.h>
@ -632,6 +633,16 @@ static int signr_convert(int sig)
#define is_ia32 0
#endif /* CONFIG_IA32_EMULATION */
#ifdef CONFIG_X86_X32_ABI
#define is_x32 test_thread_flag(TIF_X32)
static int x32_setup_rt_frame(int sig, struct k_sigaction *ka,
siginfo_t *info, compat_sigset_t *set,
struct pt_regs *regs);
#else /* !CONFIG_X86_X32_ABI */
#define is_x32 0
#endif /* CONFIG_X86_X32_ABI */
int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
sigset_t *set, struct pt_regs *regs);
int ia32_setup_frame(int sig, struct k_sigaction *ka,
@ -656,8 +667,14 @@ setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
ret = ia32_setup_rt_frame(usig, ka, info, set, regs);
else
ret = ia32_setup_frame(usig, ka, set, regs);
} else
#ifdef CONFIG_X86_X32_ABI
} else if (is_x32) {
ret = x32_setup_rt_frame(usig, ka, info,
(compat_sigset_t *)set, regs);
#endif
} else {
ret = __setup_rt_frame(sig, ka, info, set, regs);
}
if (ret) {
force_sigsegv(sig, current);
@ -840,3 +857,102 @@ void signal_fault(struct pt_regs *regs, void __user *frame, char *where)
force_sig(SIGSEGV, me);
}
#ifdef CONFIG_X86_X32_ABI
static int x32_setup_rt_frame(int sig, struct k_sigaction *ka,
siginfo_t *info, compat_sigset_t *set,
struct pt_regs *regs)
{
struct rt_sigframe_x32 __user *frame;
void __user *restorer;
int err = 0;
void __user *fpstate = NULL;
frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
return -EFAULT;
if (ka->sa.sa_flags & SA_SIGINFO) {
if (copy_siginfo_to_user32(&frame->info, info))
return -EFAULT;
}
put_user_try {
/* 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);
put_user_ex(0, &frame->uc.uc__pad0);
err |= 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 {
/* could use a vstub here */
restorer = NULL;
err |= -EFAULT;
}
put_user_ex(restorer, &frame->pretcode);
} put_user_catch(err);
if (err)
return -EFAULT;
/* Set up registers for signal handler */
regs->sp = (unsigned long) frame;
regs->ip = (unsigned long) ka->sa.sa_handler;
/* We use the x32 calling convention here... */
regs->di = sig;
regs->si = (unsigned long) &frame->info;
regs->dx = (unsigned long) &frame->uc;
loadsegment(ds, __USER_DS);
loadsegment(es, __USER_DS);
regs->cs = __USER_CS;
regs->ss = __USER_DS;
return 0;
}
asmlinkage long sys32_x32_rt_sigreturn(struct pt_regs *regs)
{
struct rt_sigframe_x32 __user *frame;
sigset_t set;
unsigned long ax;
struct pt_regs tregs;
frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8);
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
goto badframe;
if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
goto badframe;
sigdelsetmask(&set, ~_BLOCKABLE);
set_current_blocked(&set);
if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &ax))
goto badframe;
tregs = *regs;
if (sys32_sigaltstack(&frame->uc.uc_stack, NULL, &tregs) == -EFAULT)
goto badframe;
return ax;
badframe:
signal_fault(regs, frame, "x32 rt_sigreturn");
return 0;
}
#endif