License cleanup: add SPDX GPL-2.0 license identifier to files with no license
Many source files in the tree are missing licensing information, which
makes it harder for compliance tools to determine the correct license.
By default all files without license information are under the default
license of the kernel, which is GPL version 2.
Update the files which contain no license information with the 'GPL-2.0'
SPDX license identifier. The SPDX identifier is a legally binding
shorthand, which can be used instead of the full boiler plate text.
This patch is based on work done by Thomas Gleixner and Kate Stewart and
Philippe Ombredanne.
How this work was done:
Patches were generated and checked against linux-4.14-rc6 for a subset of
the use cases:
- file had no licensing information it it.
- file was a */uapi/* one with no licensing information in it,
- file was a */uapi/* one with existing licensing information,
Further patches will be generated in subsequent months to fix up cases
where non-standard license headers were used, and references to license
had to be inferred by heuristics based on keywords.
The analysis to determine which SPDX License Identifier to be applied to
a file was done in a spreadsheet of side by side results from of the
output of two independent scanners (ScanCode & Windriver) producing SPDX
tag:value files created by Philippe Ombredanne. Philippe prepared the
base worksheet, and did an initial spot review of a few 1000 files.
The 4.13 kernel was the starting point of the analysis with 60,537 files
assessed. Kate Stewart did a file by file comparison of the scanner
results in the spreadsheet to determine which SPDX license identifier(s)
to be applied to the file. She confirmed any determination that was not
immediately clear with lawyers working with the Linux Foundation.
Criteria used to select files for SPDX license identifier tagging was:
- Files considered eligible had to be source code files.
- Make and config files were included as candidates if they contained >5
lines of source
- File already had some variant of a license header in it (even if <5
lines).
All documentation files were explicitly excluded.
The following heuristics were used to determine which SPDX license
identifiers to apply.
- when both scanners couldn't find any license traces, file was
considered to have no license information in it, and the top level
COPYING file license applied.
For non */uapi/* files that summary was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 11139
and resulted in the first patch in this series.
If that file was a */uapi/* path one, it was "GPL-2.0 WITH
Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was:
SPDX license identifier # files
---------------------------------------------------|-------
GPL-2.0 WITH Linux-syscall-note 930
and resulted in the second patch in this series.
- if a file had some form of licensing information in it, and was one
of the */uapi/* ones, it was denoted with the Linux-syscall-note if
any GPL family license was found in the file or had no licensing in
it (per prior point). Results summary:
SPDX license identifier # files
---------------------------------------------------|------
GPL-2.0 WITH Linux-syscall-note 270
GPL-2.0+ WITH Linux-syscall-note 169
((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21
((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17
LGPL-2.1+ WITH Linux-syscall-note 15
GPL-1.0+ WITH Linux-syscall-note 14
((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5
LGPL-2.0+ WITH Linux-syscall-note 4
LGPL-2.1 WITH Linux-syscall-note 3
((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3
((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1
and that resulted in the third patch in this series.
- when the two scanners agreed on the detected license(s), that became
the concluded license(s).
- when there was disagreement between the two scanners (one detected a
license but the other didn't, or they both detected different
licenses) a manual inspection of the file occurred.
- In most cases a manual inspection of the information in the file
resulted in a clear resolution of the license that should apply (and
which scanner probably needed to revisit its heuristics).
- When it was not immediately clear, the license identifier was
confirmed with lawyers working with the Linux Foundation.
- If there was any question as to the appropriate license identifier,
the file was flagged for further research and to be revisited later
in time.
In total, over 70 hours of logged manual review was done on the
spreadsheet to determine the SPDX license identifiers to apply to the
source files by Kate, Philippe, Thomas and, in some cases, confirmation
by lawyers working with the Linux Foundation.
Kate also obtained a third independent scan of the 4.13 code base from
FOSSology, and compared selected files where the other two scanners
disagreed against that SPDX file, to see if there was new insights. The
Windriver scanner is based on an older version of FOSSology in part, so
they are related.
Thomas did random spot checks in about 500 files from the spreadsheets
for the uapi headers and agreed with SPDX license identifier in the
files he inspected. For the non-uapi files Thomas did random spot checks
in about 15000 files.
In initial set of patches against 4.14-rc6, 3 files were found to have
copy/paste license identifier errors, and have been fixed to reflect the
correct identifier.
Additionally Philippe spent 10 hours this week doing a detailed manual
inspection and review of the 12,461 patched files from the initial patch
version early this week with:
- a full scancode scan run, collecting the matched texts, detected
license ids and scores
- reviewing anything where there was a license detected (about 500+
files) to ensure that the applied SPDX license was correct
- reviewing anything where there was no detection but the patch license
was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied
SPDX license was correct
This produced a worksheet with 20 files needing minor correction. This
worksheet was then exported into 3 different .csv files for the
different types of files to be modified.
These .csv files were then reviewed by Greg. Thomas wrote a script to
parse the csv files and add the proper SPDX tag to the file, in the
format that the file expected. This script was further refined by Greg
based on the output to detect more types of files automatically and to
distinguish between header and source .c files (which need different
comment types.) Finally Greg ran the script using the .csv files to
generate the patches.
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-11-01 22:07:57 +08:00
|
|
|
// SPDX-License-Identifier: GPL-2.0
|
2005-04-17 06:20:36 +08:00
|
|
|
/*
|
|
|
|
* linux/arch/sh/kernel/signal.c
|
|
|
|
*
|
|
|
|
* Copyright (C) 1991, 1992 Linus Torvalds
|
|
|
|
*
|
|
|
|
* 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
|
|
|
|
*
|
|
|
|
* SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima
|
|
|
|
*
|
|
|
|
*/
|
|
|
|
#include <linux/sched.h>
|
2017-02-09 01:51:37 +08:00
|
|
|
#include <linux/sched/task_stack.h>
|
2005-04-17 06:20:36 +08:00
|
|
|
#include <linux/mm.h>
|
|
|
|
#include <linux/smp.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/stddef.h>
|
|
|
|
#include <linux/tty.h>
|
2006-09-27 17:33:49 +08:00
|
|
|
#include <linux/elf.h>
|
2005-04-17 06:20:36 +08:00
|
|
|
#include <linux/personality.h>
|
|
|
|
#include <linux/binfmts.h>
|
2007-06-01 16:26:13 +08:00
|
|
|
#include <linux/io.h>
|
2008-07-30 18:55:30 +08:00
|
|
|
#include <linux/tracehook.h>
|
2005-04-17 06:20:36 +08:00
|
|
|
#include <asm/ucontext.h>
|
2016-12-25 03:46:01 +08:00
|
|
|
#include <linux/uaccess.h>
|
2005-04-17 06:20:36 +08:00
|
|
|
#include <asm/cacheflush.h>
|
2008-09-04 17:53:58 +08:00
|
|
|
#include <asm/syscalls.h>
|
2008-03-26 18:02:47 +08:00
|
|
|
#include <asm/fpu.h>
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2008-05-19 12:40:12 +08:00
|
|
|
struct fdpic_func_descriptor {
|
|
|
|
unsigned long text;
|
|
|
|
unsigned long GOT;
|
|
|
|
};
|
|
|
|
|
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
|
|
|
/*
|
|
|
|
* The following define adds a 64 byte gap between the signal
|
|
|
|
* stack frame and previous contents of the stack. This allows
|
|
|
|
* frame unwinding in a function epilogue but only if a frame
|
|
|
|
* pointer is used in the function. This is necessary because
|
|
|
|
* current gcc compilers (<4.3) do not generate unwind info on
|
|
|
|
* SH for function epilogues.
|
|
|
|
*/
|
|
|
|
#define UNWINDGUARD 64
|
|
|
|
|
2005-04-17 06:20:36 +08:00
|
|
|
/*
|
|
|
|
* Do a signal return; undo the signal stack.
|
|
|
|
*/
|
|
|
|
|
|
|
|
#define MOVW(n) (0x9300|((n)-2)) /* Move mem word at PC+n to R3 */
|
2006-12-07 17:07:27 +08:00
|
|
|
#if defined(CONFIG_CPU_SH2)
|
2006-11-05 14:40:13 +08:00
|
|
|
#define TRAP_NOARG 0xc320 /* Syscall w/no args (NR in R3) */
|
|
|
|
#else
|
|
|
|
#define TRAP_NOARG 0xc310 /* Syscall w/no args (NR in R3) */
|
|
|
|
#endif
|
2005-04-17 06:20:36 +08:00
|
|
|
#define OR_R0_R0 0x200b /* or r0,r0 (insert to avoid hardware bug) */
|
|
|
|
|
|
|
|
struct sigframe
|
|
|
|
{
|
|
|
|
struct sigcontext sc;
|
|
|
|
unsigned long extramask[_NSIG_WORDS-1];
|
|
|
|
u16 retcode[8];
|
|
|
|
};
|
|
|
|
|
|
|
|
struct rt_sigframe
|
|
|
|
{
|
|
|
|
struct siginfo info;
|
|
|
|
struct ucontext uc;
|
|
|
|
u16 retcode[8];
|
|
|
|
};
|
|
|
|
|
|
|
|
#ifdef CONFIG_SH_FPU
|
|
|
|
static inline int restore_sigcontext_fpu(struct sigcontext __user *sc)
|
|
|
|
{
|
|
|
|
struct task_struct *tsk = current;
|
|
|
|
|
2009-10-14 13:12:41 +08:00
|
|
|
if (!(boot_cpu_data.flags & CPU_HAS_FPU))
|
2005-04-17 06:20:36 +08:00
|
|
|
return 0;
|
|
|
|
|
|
|
|
set_used_math();
|
2010-01-13 11:51:40 +08:00
|
|
|
return __copy_from_user(&tsk->thread.xstate->hardfpu, &sc->sc_fpregs[0],
|
2005-04-17 06:20:36 +08:00
|
|
|
sizeof(long)*(16*2+2));
|
|
|
|
}
|
|
|
|
|
|
|
|
static inline int save_sigcontext_fpu(struct sigcontext __user *sc,
|
|
|
|
struct pt_regs *regs)
|
|
|
|
{
|
|
|
|
struct task_struct *tsk = current;
|
|
|
|
|
2009-10-14 13:12:41 +08:00
|
|
|
if (!(boot_cpu_data.flags & CPU_HAS_FPU))
|
2005-04-17 06:20:36 +08:00
|
|
|
return 0;
|
|
|
|
|
2012-04-23 04:59:56 +08:00
|
|
|
if (!used_math())
|
|
|
|
return __put_user(0, &sc->sc_ownedfp);
|
2005-04-17 06:20:36 +08:00
|
|
|
|
2012-04-23 04:59:56 +08:00
|
|
|
if (__put_user(1, &sc->sc_ownedfp))
|
|
|
|
return -EFAULT;
|
2005-04-17 06:20:36 +08:00
|
|
|
|
|
|
|
/* This will cause a "finit" to be triggered by the next
|
|
|
|
attempted FPU operation by the 'current' process.
|
|
|
|
*/
|
|
|
|
clear_used_math();
|
|
|
|
|
|
|
|
unlazy_fpu(tsk, regs);
|
2010-01-13 11:51:40 +08:00
|
|
|
return __copy_to_user(&sc->sc_fpregs[0], &tsk->thread.xstate->hardfpu,
|
2005-04-17 06:20:36 +08:00
|
|
|
sizeof(long)*(16*2+2));
|
|
|
|
}
|
|
|
|
#endif /* CONFIG_SH_FPU */
|
|
|
|
|
|
|
|
static int
|
|
|
|
restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc, int *r0_p)
|
|
|
|
{
|
|
|
|
unsigned int err = 0;
|
|
|
|
|
|
|
|
#define COPY(x) err |= __get_user(regs->x, &sc->sc_##x)
|
|
|
|
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
|
2009-10-14 13:12:41 +08:00
|
|
|
if (boot_cpu_data.flags & CPU_HAS_FPU) {
|
2005-04-17 06:20:36 +08:00
|
|
|
int owned_fp;
|
|
|
|
struct task_struct *tsk = current;
|
|
|
|
|
|
|
|
regs->sr |= SR_FD; /* Release FPU */
|
|
|
|
clear_fpu(tsk, regs);
|
|
|
|
clear_used_math();
|
2012-04-23 04:59:56 +08:00
|
|
|
err |= __get_user (owned_fp, &sc->sc_ownedfp);
|
2005-04-17 06:20:36 +08:00
|
|
|
if (owned_fp)
|
|
|
|
err |= restore_sigcontext_fpu(sc);
|
|
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
|
|
regs->tra = -1; /* disable syscall checks */
|
|
|
|
err |= __get_user(*r0_p, &sc->sc_regs[0]);
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
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;
|
|
|
|
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
|
|
|
|
Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-04 10:57:57 +08:00
|
|
|
if (!access_ok(frame, sizeof(*frame)))
|
2005-04-17 06:20:36 +08:00
|
|
|
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))))
|
|
|
|
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:
|
2019-05-23 23:17:27 +08:00
|
|
|
force_sig(SIGSEGV);
|
2005-04-17 06:20:36 +08:00
|
|
|
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
|
|
|
|
Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-04 10:57:57 +08:00
|
|
|
if (!access_ok(frame, sizeof(*frame)))
|
2005-04-17 06:20:36 +08:00
|
|
|
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:
|
2019-05-23 23:17:27 +08:00
|
|
|
force_sig(SIGSEGV);
|
2005-04-17 06:20:36 +08:00
|
|
|
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
|
|
|
|
Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-04 10:57:57 +08:00
|
|
|
if (!access_ok(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
|
|
|
|
Remove 'type' argument from access_ok() function
Nobody has actually used the type (VERIFY_READ vs VERIFY_WRITE) argument
of the user address range verification function since we got rid of the
old racy i386-only code to walk page tables by hand.
It existed because the original 80386 would not honor the write protect
bit when in kernel mode, so you had to do COW by hand before doing any
user access. But we haven't supported that in a long time, and these
days the 'type' argument is a purely historical artifact.
A discussion about extending 'user_access_begin()' to do the range
checking resulted this patch, because there is no way we're going to
move the old VERIFY_xyz interface to that model. And it's best done at
the end of the merge window when I've done most of my merges, so let's
just get this done once and for all.
This patch was mostly done with a sed-script, with manual fix-ups for
the cases that weren't of the trivial 'access_ok(VERIFY_xyz' form.
There were a couple of notable cases:
- csky still had the old "verify_area()" name as an alias.
- the iter_iov code had magical hardcoded knowledge of the actual
values of VERIFY_{READ,WRITE} (not that they mattered, since nothing
really used it)
- microblaze used the type argument for a debug printout
but other than those oddities this should be a total no-op patch.
I tried to fix up all architectures, did fairly extensive grepping for
access_ok() uses, and the changes are trivial, but I may have missed
something. Any missed conversion should be trivially fixable, though.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-01-04 10:57:57 +08:00
|
|
|
if (!access_ok(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;
|
2020-08-24 06:36:59 +08:00
|
|
|
fallthrough;
|
2008-09-12 21:08:20 +08:00
|
|
|
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 */
|
2020-10-10 05:36:35 +08:00
|
|
|
if (thread_info_flags & (_TIF_SIGPENDING | _TIF_NOTIFY_SIGNAL))
|
2006-09-27 16:27:00 +08:00
|
|
|
do_signal(regs, save_r0);
|
2008-07-30 18:55:30 +08:00
|
|
|
|
2020-10-04 00:49:22 +08:00
|
|
|
if (thread_info_flags & _TIF_NOTIFY_RESUME)
|
2008-07-30 18:55:30 +08:00
|
|
|
tracehook_notify_resume(regs);
|
2005-04-17 06:20:36 +08:00
|
|
|
}
|