2005-04-17 06:20:36 +08:00
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/*
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* linux/arch/sh/kernel/signal.c
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*
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* Copyright (C) 1991, 1992 Linus Torvalds
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*
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* 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
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*
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* SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
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*
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*/
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#include <linux/sched.h>
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#include <linux/mm.h>
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#include <linux/smp.h>
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#include <linux/kernel.h>
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#include <linux/signal.h>
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#include <linux/errno.h>
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#include <linux/wait.h>
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#include <linux/ptrace.h>
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#include <linux/unistd.h>
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#include <linux/stddef.h>
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#include <linux/tty.h>
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2006-09-27 17:33:49 +08:00
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#include <linux/elf.h>
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2005-04-17 06:20:36 +08:00
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#include <linux/personality.h>
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#include <linux/binfmts.h>
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2007-06-01 16:26:13 +08:00
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#include <linux/io.h>
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2008-07-30 18:55:30 +08:00
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#include <linux/tracehook.h>
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2005-04-17 06:20:36 +08:00
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#include <asm/ucontext.h>
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2016-12-25 03:46:01 +08:00
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#include <linux/uaccess.h>
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2005-04-17 06:20:36 +08:00
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#include <asm/pgtable.h>
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#include <asm/cacheflush.h>
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2008-09-04 17:53:58 +08:00
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#include <asm/syscalls.h>
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2008-03-26 18:02:47 +08:00
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#include <asm/fpu.h>
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2005-04-17 06:20:36 +08:00
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2008-05-19 12:40:12 +08:00
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struct fdpic_func_descriptor {
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unsigned long text;
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unsigned long GOT;
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};
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sh: Improve unwind info for signals
GCC does not issue unwind information for function epilogues.
Unfortunately we can catch a signal during an epilogue. The signal
handler writes the current context and signal return code onto the stack
overwriting previous contents. During unwinding, libgcc can try to
restore registers from the stack and restores corrupted ones. This can
lead to segmentation, misaligned access and sigbus faults.
For example, consider the following code:
mov.l r12,@-r15
mov.l r14,@-r15
sts.l pr,@-r15
mov r15,r14
<do stuff>
mov r14, r15
lds.l @r15+, pr
<<< SIGNAL HERE
mov.l @r15+, r14
mov.l @r15+, r12
rts
Unwind is aware that pr was pushed to stack in prolog, so tries to
restore it. Unfortunately it restores the last word of the signal
handler code placed on the stack by the kernel.
This patch tries to avoid the problem by adding a guard region on the
stack between where the function pushes data and where the signal handler
pushes its return code. We probably don't see this problem often because
exception handling unwinding in an epilogue only occurs due to a pthread
cancel signal. Also the kernel signal stack handler alignment of 8 bytes
could hide the occurance of this problem sometimes as the stack may not
be trampled at a particular required word.
This is not guaranteed to always work. It relies on a frame pointer
existing for the function (so it can get the correct sp value) which is
not always the case for the SH4.
Modifications will also be made to libgcc for the case where there is no
fp.
Signed-off-by: Carl Shaw <carl.shaw@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-24 14:07:08 +08:00
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/*
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* The following define adds a 64 byte gap between the signal
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* stack frame and previous contents of the stack. This allows
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* frame unwinding in a function epilogue but only if a frame
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* pointer is used in the function. This is necessary because
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* current gcc compilers (<4.3) do not generate unwind info on
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* SH for function epilogues.
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*/
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#define UNWINDGUARD 64
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2005-04-17 06:20:36 +08:00
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/*
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* Do a signal return; undo the signal stack.
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*/
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#define MOVW(n) (0x9300|((n)-2)) /* Move mem word at PC+n to R3 */
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2006-12-07 17:07:27 +08:00
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#if defined(CONFIG_CPU_SH2)
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2006-11-05 14:40:13 +08:00
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#define TRAP_NOARG 0xc320 /* Syscall w/no args (NR in R3) */
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#else
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#define TRAP_NOARG 0xc310 /* Syscall w/no args (NR in R3) */
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#endif
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2005-04-17 06:20:36 +08:00
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#define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */
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struct sigframe
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{
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struct sigcontext sc;
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unsigned long extramask[_NSIG_WORDS-1];
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u16 retcode[8];
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};
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struct rt_sigframe
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{
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struct siginfo info;
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struct ucontext uc;
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u16 retcode[8];
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};
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#ifdef CONFIG_SH_FPU
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static inline int restore_sigcontext_fpu(struct sigcontext __user *sc)
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{
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struct task_struct *tsk = current;
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2009-10-14 13:12:41 +08:00
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if (!(boot_cpu_data.flags & CPU_HAS_FPU))
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2005-04-17 06:20:36 +08:00
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return 0;
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set_used_math();
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2010-01-13 11:51:40 +08:00
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return __copy_from_user(&tsk->thread.xstate->hardfpu, &sc->sc_fpregs[0],
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2005-04-17 06:20:36 +08:00
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sizeof(long)*(16*2+2));
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}
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static inline int save_sigcontext_fpu(struct sigcontext __user *sc,
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struct pt_regs *regs)
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{
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struct task_struct *tsk = current;
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2009-10-14 13:12:41 +08:00
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if (!(boot_cpu_data.flags & CPU_HAS_FPU))
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2005-04-17 06:20:36 +08:00
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return 0;
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2012-04-23 04:59:56 +08:00
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if (!used_math())
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return __put_user(0, &sc->sc_ownedfp);
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2005-04-17 06:20:36 +08:00
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2012-04-23 04:59:56 +08:00
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if (__put_user(1, &sc->sc_ownedfp))
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return -EFAULT;
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2005-04-17 06:20:36 +08:00
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/* This will cause a "finit" to be triggered by the next
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attempted FPU operation by the 'current' process.
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*/
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clear_used_math();
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unlazy_fpu(tsk, regs);
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2010-01-13 11:51:40 +08:00
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return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.xstate->hardfpu,
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2005-04-17 06:20:36 +08:00
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sizeof(long)*(16*2+2));
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}
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#endif /* CONFIG_SH_FPU */
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static int
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restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p)
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{
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unsigned int err = 0;
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#define COPY(x) err |= __get_user(regs->x, &sc->sc_##x)
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COPY(regs[1]);
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COPY(regs[2]); COPY(regs[3]);
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COPY(regs[4]); COPY(regs[5]);
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COPY(regs[6]); COPY(regs[7]);
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COPY(regs[8]); COPY(regs[9]);
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COPY(regs[10]); COPY(regs[11]);
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COPY(regs[12]); COPY(regs[13]);
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COPY(regs[14]); COPY(regs[15]);
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COPY(gbr); COPY(mach);
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COPY(macl); COPY(pr);
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COPY(sr); COPY(pc);
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#undef COPY
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#ifdef CONFIG_SH_FPU
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2009-10-14 13:12:41 +08:00
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if (boot_cpu_data.flags & CPU_HAS_FPU) {
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2005-04-17 06:20:36 +08:00
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int owned_fp;
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struct task_struct *tsk = current;
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regs->sr |= SR_FD; /* Release FPU */
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clear_fpu(tsk, regs);
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clear_used_math();
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2012-04-23 04:59:56 +08:00
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err |= __get_user (owned_fp, &sc->sc_ownedfp);
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2005-04-17 06:20:36 +08:00
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if (owned_fp)
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err |= restore_sigcontext_fpu(sc);
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}
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#endif
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regs->tra = -1; /* disable syscall checks */
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err |= __get_user(*r0_p, &sc->sc_regs[0]);
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return err;
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}
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sh: push extra copy of r0-r2 for syscall parameters
When invoking syscall handlers on sh32, the saved userspace registers
are at the top of the stack. This seems to have been intentional, as it
is an easy way to pass r0, r1, ... to the handler as parameters 5, 6,
...
It causes problems, however, because the compiler is allowed to generate
code for a function which clobbers that function's own parameters. For
example, gcc generates the following code for clone:
<SyS_clone>:
mov.l 8c020714 <SyS_clone+0xc>,r1 ! 8c020540 <do_fork>
mov.l r7,@r15
mov r6,r7
jmp @r1
mov #0,r6
nop
.word 0x0540
.word 0x8c02
The `mov.l r7,@r15` clobbers the saved value of r0 passed from
userspace. For most system calls, this might not be a problem, because
we'll be overwriting r0 with the return value anyway. But in the case
of clone, copy_thread will need the original value of r0 if the
CLONE_SETTLS flag was specified.
The first patch in this series fixes this issue for system calls by
pushing to the stack and extra copy of r0-r2 before invoking the
handler. We discard this copy before restoring the userspace registers,
so it is not a problem if they are clobbered.
Exception handlers also receive the userspace register values in a
similar manner, and may hit the same problem. The second patch removes
the do_fpu_error handler, which looks susceptible to this problem and
which, as far as I can tell, has not been used in some time. The third
patch addresses other exception handlers.
This patch (of 3):
The userspace registers are stored at the top of the stack when the
syscall handler is invoked, which allows r0-r2 to act as parameters 5-7.
Parameters passed on the stack may be clobbered by the syscall handler.
The solution is to push an extra copy of the registers which might be
used as syscall parameters to the stack, so that the authoritative set
of saved register values does not get clobbered.
A few system call handlers are also updated to get the userspace
registers using current_pt_regs() instead of from the stack.
Signed-off-by: Bobby Bingham <koorogi@koorogi.info>
Cc: Paul Mundt <paul.mundt@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-04 05:46:39 +08:00
|
|
|
asmlinkage int sys_sigreturn(void)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
sh: push extra copy of r0-r2 for syscall parameters
When invoking syscall handlers on sh32, the saved userspace registers
are at the top of the stack. This seems to have been intentional, as it
is an easy way to pass r0, r1, ... to the handler as parameters 5, 6,
...
It causes problems, however, because the compiler is allowed to generate
code for a function which clobbers that function's own parameters. For
example, gcc generates the following code for clone:
<SyS_clone>:
mov.l 8c020714 <SyS_clone+0xc>,r1 ! 8c020540 <do_fork>
mov.l r7,@r15
mov r6,r7
jmp @r1
mov #0,r6
nop
.word 0x0540
.word 0x8c02
The `mov.l r7,@r15` clobbers the saved value of r0 passed from
userspace. For most system calls, this might not be a problem, because
we'll be overwriting r0 with the return value anyway. But in the case
of clone, copy_thread will need the original value of r0 if the
CLONE_SETTLS flag was specified.
The first patch in this series fixes this issue for system calls by
pushing to the stack and extra copy of r0-r2 before invoking the
handler. We discard this copy before restoring the userspace registers,
so it is not a problem if they are clobbered.
Exception handlers also receive the userspace register values in a
similar manner, and may hit the same problem. The second patch removes
the do_fpu_error handler, which looks susceptible to this problem and
which, as far as I can tell, has not been used in some time. The third
patch addresses other exception handlers.
This patch (of 3):
The userspace registers are stored at the top of the stack when the
syscall handler is invoked, which allows r0-r2 to act as parameters 5-7.
Parameters passed on the stack may be clobbered by the syscall handler.
The solution is to push an extra copy of the registers which might be
used as syscall parameters to the stack, so that the authoritative set
of saved register values does not get clobbered.
A few system call handlers are also updated to get the userspace
registers using current_pt_regs() instead of from the stack.
Signed-off-by: Bobby Bingham <koorogi@koorogi.info>
Cc: Paul Mundt <paul.mundt@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-04 05:46:39 +08:00
|
|
|
struct pt_regs *regs = current_pt_regs();
|
2006-11-21 10:16:57 +08:00
|
|
|
struct sigframe __user *frame = (struct sigframe __user *)regs->regs[15];
|
2005-04-17 06:20:36 +08:00
|
|
|
sigset_t set;
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|
|
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int r0;
|
|
|
|
|
2008-09-24 13:37:35 +08:00
|
|
|
/* Always make any pending restarted system calls return -EINTR */
|
2015-02-13 07:01:14 +08:00
|
|
|
current->restart_block.fn = do_no_restart_syscall;
|
2008-09-24 13:37:35 +08:00
|
|
|
|
2005-04-17 06:20:36 +08:00
|
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|
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
|
|
|
|
goto badframe;
|
|
|
|
|
|
|
|
if (__get_user(set.sig[0], &frame->sc.oldmask)
|
|
|
|
|| (_NSIG_WORDS > 1
|
|
|
|
&& __copy_from_user(&set.sig[1], &frame->extramask,
|
|
|
|
sizeof(frame->extramask))))
|
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|
|
goto badframe;
|
|
|
|
|
2012-03-29 06:16:32 +08:00
|
|
|
set_current_blocked(&set);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2006-11-21 10:16:57 +08:00
|
|
|
if (restore_sigcontext(regs, &frame->sc, &r0))
|
2005-04-17 06:20:36 +08:00
|
|
|
goto badframe;
|
|
|
|
return r0;
|
|
|
|
|
|
|
|
badframe:
|
|
|
|
force_sig(SIGSEGV, current);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
sh: push extra copy of r0-r2 for syscall parameters
When invoking syscall handlers on sh32, the saved userspace registers
are at the top of the stack. This seems to have been intentional, as it
is an easy way to pass r0, r1, ... to the handler as parameters 5, 6,
...
It causes problems, however, because the compiler is allowed to generate
code for a function which clobbers that function's own parameters. For
example, gcc generates the following code for clone:
<SyS_clone>:
mov.l 8c020714 <SyS_clone+0xc>,r1 ! 8c020540 <do_fork>
mov.l r7,@r15
mov r6,r7
jmp @r1
mov #0,r6
nop
.word 0x0540
.word 0x8c02
The `mov.l r7,@r15` clobbers the saved value of r0 passed from
userspace. For most system calls, this might not be a problem, because
we'll be overwriting r0 with the return value anyway. But in the case
of clone, copy_thread will need the original value of r0 if the
CLONE_SETTLS flag was specified.
The first patch in this series fixes this issue for system calls by
pushing to the stack and extra copy of r0-r2 before invoking the
handler. We discard this copy before restoring the userspace registers,
so it is not a problem if they are clobbered.
Exception handlers also receive the userspace register values in a
similar manner, and may hit the same problem. The second patch removes
the do_fpu_error handler, which looks susceptible to this problem and
which, as far as I can tell, has not been used in some time. The third
patch addresses other exception handlers.
This patch (of 3):
The userspace registers are stored at the top of the stack when the
syscall handler is invoked, which allows r0-r2 to act as parameters 5-7.
Parameters passed on the stack may be clobbered by the syscall handler.
The solution is to push an extra copy of the registers which might be
used as syscall parameters to the stack, so that the authoritative set
of saved register values does not get clobbered.
A few system call handlers are also updated to get the userspace
registers using current_pt_regs() instead of from the stack.
Signed-off-by: Bobby Bingham <koorogi@koorogi.info>
Cc: Paul Mundt <paul.mundt@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-04 05:46:39 +08:00
|
|
|
asmlinkage int sys_rt_sigreturn(void)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
sh: push extra copy of r0-r2 for syscall parameters
When invoking syscall handlers on sh32, the saved userspace registers
are at the top of the stack. This seems to have been intentional, as it
is an easy way to pass r0, r1, ... to the handler as parameters 5, 6,
...
It causes problems, however, because the compiler is allowed to generate
code for a function which clobbers that function's own parameters. For
example, gcc generates the following code for clone:
<SyS_clone>:
mov.l 8c020714 <SyS_clone+0xc>,r1 ! 8c020540 <do_fork>
mov.l r7,@r15
mov r6,r7
jmp @r1
mov #0,r6
nop
.word 0x0540
.word 0x8c02
The `mov.l r7,@r15` clobbers the saved value of r0 passed from
userspace. For most system calls, this might not be a problem, because
we'll be overwriting r0 with the return value anyway. But in the case
of clone, copy_thread will need the original value of r0 if the
CLONE_SETTLS flag was specified.
The first patch in this series fixes this issue for system calls by
pushing to the stack and extra copy of r0-r2 before invoking the
handler. We discard this copy before restoring the userspace registers,
so it is not a problem if they are clobbered.
Exception handlers also receive the userspace register values in a
similar manner, and may hit the same problem. The second patch removes
the do_fpu_error handler, which looks susceptible to this problem and
which, as far as I can tell, has not been used in some time. The third
patch addresses other exception handlers.
This patch (of 3):
The userspace registers are stored at the top of the stack when the
syscall handler is invoked, which allows r0-r2 to act as parameters 5-7.
Parameters passed on the stack may be clobbered by the syscall handler.
The solution is to push an extra copy of the registers which might be
used as syscall parameters to the stack, so that the authoritative set
of saved register values does not get clobbered.
A few system call handlers are also updated to get the userspace
registers using current_pt_regs() instead of from the stack.
Signed-off-by: Bobby Bingham <koorogi@koorogi.info>
Cc: Paul Mundt <paul.mundt@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2014-04-04 05:46:39 +08:00
|
|
|
struct pt_regs *regs = current_pt_regs();
|
2006-11-21 10:16:57 +08:00
|
|
|
struct rt_sigframe __user *frame = (struct rt_sigframe __user *)regs->regs[15];
|
2005-04-17 06:20:36 +08:00
|
|
|
sigset_t set;
|
|
|
|
int r0;
|
|
|
|
|
2008-09-24 13:37:35 +08:00
|
|
|
/* Always make any pending restarted system calls return -EINTR */
|
2015-02-13 07:01:14 +08:00
|
|
|
current->restart_block.fn = do_no_restart_syscall;
|
2008-09-24 13:37:35 +08:00
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
if (!access_ok(VERIFY_READ, frame, sizeof(*frame)))
|
|
|
|
goto badframe;
|
|
|
|
|
|
|
|
if (__copy_from_user(&set, &frame->uc.uc_sigmask, sizeof(set)))
|
|
|
|
goto badframe;
|
|
|
|
|
2012-03-29 06:16:32 +08:00
|
|
|
set_current_blocked(&set);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2006-11-21 10:16:57 +08:00
|
|
|
if (restore_sigcontext(regs, &frame->uc.uc_mcontext, &r0))
|
2005-04-17 06:20:36 +08:00
|
|
|
goto badframe;
|
|
|
|
|
2012-12-23 16:46:05 +08:00
|
|
|
if (restore_altstack(&frame->uc.uc_stack))
|
2005-04-17 06:20:36 +08:00
|
|
|
goto badframe;
|
|
|
|
|
|
|
|
return r0;
|
|
|
|
|
|
|
|
badframe:
|
|
|
|
force_sig(SIGSEGV, current);
|
|
|
|
return 0;
|
2007-06-19 11:33:21 +08:00
|
|
|
}
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
/*
|
|
|
|
* Set up a signal frame.
|
|
|
|
*/
|
|
|
|
|
|
|
|
static int
|
|
|
|
setup_sigcontext(struct sigcontext __user *sc, struct pt_regs *regs,
|
|
|
|
unsigned long mask)
|
|
|
|
{
|
|
|
|
int err = 0;
|
|
|
|
|
|
|
|
#define COPY(x) err |= __put_user(regs->x, &sc->sc_##x)
|
|
|
|
COPY(regs[0]); COPY(regs[1]);
|
|
|
|
COPY(regs[2]); COPY(regs[3]);
|
|
|
|
COPY(regs[4]); COPY(regs[5]);
|
|
|
|
COPY(regs[6]); COPY(regs[7]);
|
|
|
|
COPY(regs[8]); COPY(regs[9]);
|
|
|
|
COPY(regs[10]); COPY(regs[11]);
|
|
|
|
COPY(regs[12]); COPY(regs[13]);
|
|
|
|
COPY(regs[14]); COPY(regs[15]);
|
|
|
|
COPY(gbr); COPY(mach);
|
|
|
|
COPY(macl); COPY(pr);
|
|
|
|
COPY(sr); COPY(pc);
|
|
|
|
#undef COPY
|
|
|
|
|
|
|
|
#ifdef CONFIG_SH_FPU
|
|
|
|
err |= save_sigcontext_fpu(sc, regs);
|
|
|
|
#endif
|
|
|
|
|
|
|
|
/* non-iBCS2 extensions.. */
|
|
|
|
err |= __put_user(mask, &sc->oldmask);
|
|
|
|
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Determine which stack to use..
|
|
|
|
*/
|
|
|
|
static inline void __user *
|
|
|
|
get_sigframe(struct k_sigaction *ka, unsigned long sp, size_t frame_size)
|
|
|
|
{
|
|
|
|
if (ka->sa.sa_flags & SA_ONSTACK) {
|
|
|
|
if (sas_ss_flags(sp) == 0)
|
|
|
|
sp = current->sas_ss_sp + current->sas_ss_size;
|
|
|
|
}
|
|
|
|
|
sh: Improve unwind info for signals
GCC does not issue unwind information for function epilogues.
Unfortunately we can catch a signal during an epilogue. The signal
handler writes the current context and signal return code onto the stack
overwriting previous contents. During unwinding, libgcc can try to
restore registers from the stack and restores corrupted ones. This can
lead to segmentation, misaligned access and sigbus faults.
For example, consider the following code:
mov.l r12,@-r15
mov.l r14,@-r15
sts.l pr,@-r15
mov r15,r14
<do stuff>
mov r14, r15
lds.l @r15+, pr
<<< SIGNAL HERE
mov.l @r15+, r14
mov.l @r15+, r12
rts
Unwind is aware that pr was pushed to stack in prolog, so tries to
restore it. Unfortunately it restores the last word of the signal
handler code placed on the stack by the kernel.
This patch tries to avoid the problem by adding a guard region on the
stack between where the function pushes data and where the signal handler
pushes its return code. We probably don't see this problem often because
exception handling unwinding in an epilogue only occurs due to a pthread
cancel signal. Also the kernel signal stack handler alignment of 8 bytes
could hide the occurance of this problem sometimes as the stack may not
be trampled at a particular required word.
This is not guaranteed to always work. It relies on a frame pointer
existing for the function (so it can get the correct sp value) which is
not always the case for the SH4.
Modifications will also be made to libgcc for the case where there is no
fp.
Signed-off-by: Carl Shaw <carl.shaw@st.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2009-08-24 14:07:08 +08:00
|
|
|
return (void __user *)((sp - (frame_size+UNWINDGUARD)) & -8ul);
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
2006-09-27 17:33:49 +08:00
|
|
|
/* These symbols are defined with the addresses in the vsyscall page.
|
|
|
|
See vsyscall-trapa.S. */
|
2009-06-18 17:03:33 +08:00
|
|
|
extern void __kernel_sigreturn(void);
|
|
|
|
extern void __kernel_rt_sigreturn(void);
|
2006-09-27 17:33:49 +08:00
|
|
|
|
2013-10-07 20:51:14 +08:00
|
|
|
static int setup_frame(struct ksignal *ksig, sigset_t *set,
|
|
|
|
struct pt_regs *regs)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
struct sigframe __user *frame;
|
2013-10-07 20:51:14 +08:00
|
|
|
int err = 0, sig = ksig->sig;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2013-10-07 20:51:14 +08:00
|
|
|
frame = get_sigframe(&ksig->ka, regs->regs[15], sizeof(*frame));
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
|
2013-10-07 20:51:14 +08:00
|
|
|
return -EFAULT;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
err |= setup_sigcontext(&frame->sc, regs, set->sig[0]);
|
|
|
|
|
2006-09-27 16:27:00 +08:00
|
|
|
if (_NSIG_WORDS > 1)
|
2005-04-17 06:20:36 +08:00
|
|
|
err |= __copy_to_user(frame->extramask, &set->sig[1],
|
|
|
|
sizeof(frame->extramask));
|
|
|
|
|
|
|
|
/* Set up to return from userspace. If provided, use a stub
|
|
|
|
already in userspace. */
|
2013-10-07 20:51:14 +08:00
|
|
|
if (ksig->ka.sa.sa_flags & SA_RESTORER) {
|
|
|
|
regs->pr = (unsigned long) ksig->ka.sa.sa_restorer;
|
2006-09-27 17:33:49 +08:00
|
|
|
#ifdef CONFIG_VSYSCALL
|
|
|
|
} else if (likely(current->mm->context.vdso)) {
|
|
|
|
regs->pr = VDSO_SYM(&__kernel_sigreturn);
|
|
|
|
#endif
|
2005-04-17 06:20:36 +08:00
|
|
|
} else {
|
|
|
|
/* Generate return code (system call to sigreturn) */
|
|
|
|
err |= __put_user(MOVW(7), &frame->retcode[0]);
|
2006-11-05 14:40:13 +08:00
|
|
|
err |= __put_user(TRAP_NOARG, &frame->retcode[1]);
|
2005-04-17 06:20:36 +08:00
|
|
|
err |= __put_user(OR_R0_R0, &frame->retcode[2]);
|
|
|
|
err |= __put_user(OR_R0_R0, &frame->retcode[3]);
|
|
|
|
err |= __put_user(OR_R0_R0, &frame->retcode[4]);
|
|
|
|
err |= __put_user(OR_R0_R0, &frame->retcode[5]);
|
|
|
|
err |= __put_user(OR_R0_R0, &frame->retcode[6]);
|
|
|
|
err |= __put_user((__NR_sigreturn), &frame->retcode[7]);
|
|
|
|
regs->pr = (unsigned long) frame->retcode;
|
2008-07-02 16:51:23 +08:00
|
|
|
flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode));
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
if (err)
|
2013-10-07 20:51:14 +08:00
|
|
|
return -EFAULT;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
/* Set up registers for signal handler */
|
|
|
|
regs->regs[15] = (unsigned long) frame;
|
2014-07-13 23:37:45 +08:00
|
|
|
regs->regs[4] = sig; /* Arg for signal handler */
|
2005-04-17 06:20:36 +08:00
|
|
|
regs->regs[5] = 0;
|
|
|
|
regs->regs[6] = (unsigned long) &frame->sc;
|
2008-05-19 12:40:12 +08:00
|
|
|
|
|
|
|
if (current->personality & FDPIC_FUNCPTRS) {
|
|
|
|
struct fdpic_func_descriptor __user *funcptr =
|
2013-10-07 20:51:14 +08:00
|
|
|
(struct fdpic_func_descriptor __user *)ksig->ka.sa.sa_handler;
|
2008-05-19 12:40:12 +08:00
|
|
|
|
2012-04-23 04:59:56 +08:00
|
|
|
err |= __get_user(regs->pc, &funcptr->text);
|
|
|
|
err |= __get_user(regs->regs[12], &funcptr->GOT);
|
2008-05-19 12:40:12 +08:00
|
|
|
} else
|
2013-10-07 20:51:14 +08:00
|
|
|
regs->pc = (unsigned long)ksig->ka.sa.sa_handler;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2012-04-23 04:59:56 +08:00
|
|
|
if (err)
|
2013-10-07 20:51:14 +08:00
|
|
|
return -EFAULT;
|
2012-04-23 04:59:56 +08:00
|
|
|
|
2006-09-27 16:27:00 +08:00
|
|
|
pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
|
2007-10-19 14:40:41 +08:00
|
|
|
current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2006-09-27 16:27:00 +08:00
|
|
|
return 0;
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
2013-10-07 20:51:14 +08:00
|
|
|
static int setup_rt_frame(struct ksignal *ksig, sigset_t *set,
|
|
|
|
struct pt_regs *regs)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
|
|
|
struct rt_sigframe __user *frame;
|
2013-10-07 20:51:14 +08:00
|
|
|
int err = 0, sig = ksig->sig;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2013-10-07 20:51:14 +08:00
|
|
|
frame = get_sigframe(&ksig->ka, regs->regs[15], sizeof(*frame));
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
|
2013-10-07 20:51:14 +08:00
|
|
|
return -EFAULT;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2013-10-07 20:51:14 +08:00
|
|
|
err |= copy_siginfo_to_user(&frame->info, &ksig->info);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
/* Create the ucontext. */
|
|
|
|
err |= __put_user(0, &frame->uc.uc_flags);
|
2008-09-04 17:53:58 +08:00
|
|
|
err |= __put_user(NULL, &frame->uc.uc_link);
|
2012-12-23 16:46:05 +08:00
|
|
|
err |= __save_altstack(&frame->uc.uc_stack, regs->regs[15]);
|
2005-04-17 06:20:36 +08:00
|
|
|
err |= setup_sigcontext(&frame->uc.uc_mcontext,
|
|
|
|
regs, set->sig[0]);
|
|
|
|
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
|
|
|
|
|
|
|
|
/* Set up to return from userspace. If provided, use a stub
|
|
|
|
already in userspace. */
|
2013-10-07 20:51:14 +08:00
|
|
|
if (ksig->ka.sa.sa_flags & SA_RESTORER) {
|
|
|
|
regs->pr = (unsigned long) ksig->ka.sa.sa_restorer;
|
2006-09-27 17:33:49 +08:00
|
|
|
#ifdef CONFIG_VSYSCALL
|
|
|
|
} else if (likely(current->mm->context.vdso)) {
|
|
|
|
regs->pr = VDSO_SYM(&__kernel_rt_sigreturn);
|
|
|
|
#endif
|
2005-04-17 06:20:36 +08:00
|
|
|
} else {
|
|
|
|
/* Generate return code (system call to rt_sigreturn) */
|
|
|
|
err |= __put_user(MOVW(7), &frame->retcode[0]);
|
2006-11-05 14:40:13 +08:00
|
|
|
err |= __put_user(TRAP_NOARG, &frame->retcode[1]);
|
2005-04-17 06:20:36 +08:00
|
|
|
err |= __put_user(OR_R0_R0, &frame->retcode[2]);
|
|
|
|
err |= __put_user(OR_R0_R0, &frame->retcode[3]);
|
|
|
|
err |= __put_user(OR_R0_R0, &frame->retcode[4]);
|
|
|
|
err |= __put_user(OR_R0_R0, &frame->retcode[5]);
|
|
|
|
err |= __put_user(OR_R0_R0, &frame->retcode[6]);
|
|
|
|
err |= __put_user((__NR_rt_sigreturn), &frame->retcode[7]);
|
|
|
|
regs->pr = (unsigned long) frame->retcode;
|
2009-10-14 13:21:40 +08:00
|
|
|
flush_icache_range(regs->pr, regs->pr + sizeof(frame->retcode));
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
if (err)
|
2013-10-07 20:51:14 +08:00
|
|
|
return -EFAULT;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
/* Set up registers for signal handler */
|
|
|
|
regs->regs[15] = (unsigned long) frame;
|
2014-07-13 23:37:45 +08:00
|
|
|
regs->regs[4] = sig; /* Arg for signal handler */
|
2005-04-17 06:20:36 +08:00
|
|
|
regs->regs[5] = (unsigned long) &frame->info;
|
|
|
|
regs->regs[6] = (unsigned long) &frame->uc;
|
2008-05-19 12:40:12 +08:00
|
|
|
|
|
|
|
if (current->personality & FDPIC_FUNCPTRS) {
|
|
|
|
struct fdpic_func_descriptor __user *funcptr =
|
2013-10-07 20:51:14 +08:00
|
|
|
(struct fdpic_func_descriptor __user *)ksig->ka.sa.sa_handler;
|
2008-05-19 12:40:12 +08:00
|
|
|
|
2012-04-23 04:59:56 +08:00
|
|
|
err |= __get_user(regs->pc, &funcptr->text);
|
|
|
|
err |= __get_user(regs->regs[12], &funcptr->GOT);
|
2008-05-19 12:40:12 +08:00
|
|
|
} else
|
2013-10-07 20:51:14 +08:00
|
|
|
regs->pc = (unsigned long)ksig->ka.sa.sa_handler;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2012-04-23 04:59:56 +08:00
|
|
|
if (err)
|
2013-10-07 20:51:14 +08:00
|
|
|
return -EFAULT;
|
2012-04-23 04:59:56 +08:00
|
|
|
|
2006-09-27 16:27:00 +08:00
|
|
|
pr_debug("SIG deliver (%s:%d): sp=%p pc=%08lx pr=%08lx\n",
|
2007-10-19 14:40:41 +08:00
|
|
|
current->comm, task_pid_nr(current), frame, regs->pc, regs->pr);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2006-09-27 16:27:00 +08:00
|
|
|
return 0;
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
2008-09-12 21:08:20 +08:00
|
|
|
static inline void
|
|
|
|
handle_syscall_restart(unsigned long save_r0, struct pt_regs *regs,
|
|
|
|
struct sigaction *sa)
|
|
|
|
{
|
|
|
|
/* If we're not from a syscall, bail out */
|
|
|
|
if (regs->tra < 0)
|
|
|
|
return;
|
|
|
|
|
|
|
|
/* check for system call restart.. */
|
|
|
|
switch (regs->regs[0]) {
|
|
|
|
case -ERESTART_RESTARTBLOCK:
|
|
|
|
case -ERESTARTNOHAND:
|
|
|
|
no_system_call_restart:
|
|
|
|
regs->regs[0] = -EINTR;
|
|
|
|
break;
|
|
|
|
|
|
|
|
case -ERESTARTSYS:
|
|
|
|
if (!(sa->sa_flags & SA_RESTART))
|
|
|
|
goto no_system_call_restart;
|
|
|
|
/* fallthrough */
|
|
|
|
case -ERESTARTNOINTR:
|
|
|
|
regs->regs[0] = save_r0;
|
2010-01-26 11:58:40 +08:00
|
|
|
regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
|
2008-09-12 21:08:20 +08:00
|
|
|
break;
|
|
|
|
}
|
|
|
|
}
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
/*
|
|
|
|
* OK, we're invoking a handler
|
|
|
|
*/
|
2012-05-22 11:42:15 +08:00
|
|
|
static void
|
2013-10-07 20:51:14 +08:00
|
|
|
handle_signal(struct ksignal *ksig, struct pt_regs *regs, unsigned int save_r0)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
2012-05-02 21:59:21 +08:00
|
|
|
sigset_t *oldset = sigmask_to_save();
|
2006-09-27 16:27:00 +08:00
|
|
|
int ret;
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
/* Set up the stack frame */
|
2013-10-07 20:51:14 +08:00
|
|
|
if (ksig->ka.sa.sa_flags & SA_SIGINFO)
|
|
|
|
ret = setup_rt_frame(ksig, oldset, regs);
|
2005-04-17 06:20:36 +08:00
|
|
|
else
|
2013-10-07 20:51:14 +08:00
|
|
|
ret = setup_frame(ksig, oldset, regs);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2013-10-07 20:51:14 +08:00
|
|
|
signal_setup_done(ret, ksig, test_thread_flag(TIF_SINGLESTEP));
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* 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.
|
|
|
|
*
|
|
|
|
* Note that we go through the signals twice: once to check the signals that
|
|
|
|
* the kernel can handle, and then we build all the user-level signal handling
|
|
|
|
* stack-frames in one go after that.
|
|
|
|
*/
|
2006-09-27 16:27:00 +08:00
|
|
|
static void do_signal(struct pt_regs *regs, unsigned int save_r0)
|
2005-04-17 06:20:36 +08:00
|
|
|
{
|
2013-10-07 20:51:14 +08:00
|
|
|
struct ksignal ksig;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
/*
|
|
|
|
* We want the common case to go fast, which
|
|
|
|
* is why we may in certain cases get here from
|
|
|
|
* kernel mode. Just return without doing anything
|
|
|
|
* if so.
|
|
|
|
*/
|
|
|
|
if (!user_mode(regs))
|
2006-09-27 16:27:00 +08:00
|
|
|
return;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2013-10-07 20:51:14 +08:00
|
|
|
if (get_signal(&ksig)) {
|
|
|
|
handle_syscall_restart(save_r0, regs, &ksig.ka.sa);
|
2008-09-12 21:08:20 +08:00
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
/* Whee! Actually deliver the signal. */
|
2013-10-07 20:51:14 +08:00
|
|
|
handle_signal(&ksig, regs, save_r0);
|
2007-02-23 12:22:56 +08:00
|
|
|
return;
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
/* Did we come from a system call? */
|
|
|
|
if (regs->tra >= 0) {
|
|
|
|
/* Restart the system call - no handlers present */
|
|
|
|
if (regs->regs[0] == -ERESTARTNOHAND ||
|
|
|
|
regs->regs[0] == -ERESTARTSYS ||
|
2006-09-27 16:22:49 +08:00
|
|
|
regs->regs[0] == -ERESTARTNOINTR) {
|
2007-02-23 12:22:56 +08:00
|
|
|
regs->regs[0] = save_r0;
|
2010-01-26 11:58:40 +08:00
|
|
|
regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
|
2006-09-27 16:22:49 +08:00
|
|
|
} else if (regs->regs[0] == -ERESTART_RESTARTBLOCK) {
|
2010-01-26 11:58:40 +08:00
|
|
|
regs->pc -= instruction_size(__raw_readw(regs->pc - 4));
|
2006-09-27 16:22:49 +08:00
|
|
|
regs->regs[3] = __NR_restart_syscall;
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|
|
|
|
}
|
2006-09-27 16:27:00 +08:00
|
|
|
|
2009-10-14 15:05:42 +08:00
|
|
|
/*
|
|
|
|
* If there's no signal to deliver, we just put the saved sigmask
|
|
|
|
* back.
|
|
|
|
*/
|
2012-05-22 11:33:55 +08:00
|
|
|
restore_saved_sigmask();
|
2006-09-27 16:27:00 +08:00
|
|
|
}
|
|
|
|
|
|
|
|
asmlinkage void do_notify_resume(struct pt_regs *regs, unsigned int save_r0,
|
2008-07-30 18:55:30 +08:00
|
|
|
unsigned long thread_info_flags)
|
2006-09-27 16:27:00 +08:00
|
|
|
{
|
|
|
|
/* deal with pending signal delivery */
|
2008-07-30 18:55:30 +08:00
|
|
|
if (thread_info_flags & _TIF_SIGPENDING)
|
2006-09-27 16:27:00 +08:00
|
|
|
do_signal(regs, save_r0);
|
2008-07-30 18:55:30 +08:00
|
|
|
|
|
|
|
if (thread_info_flags & _TIF_NOTIFY_RESUME) {
|
|
|
|
clear_thread_flag(TIF_NOTIFY_RESUME);
|
|
|
|
tracehook_notify_resume(regs);
|
|
|
|
}
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|