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Diffstat (limited to 'arch/x86/kernel/signal_32.c')
-rw-r--r--arch/x86/kernel/signal_32.c222
1 files changed, 134 insertions, 88 deletions
diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index b21070ea33a4..d6dd057d0f22 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -27,6 +27,7 @@
#include <asm/uaccess.h>
#include <asm/i387.h>
#include <asm/vdso.h>
+#include <asm/syscall.h>
#include <asm/syscalls.h>
#include "sigframe.h"
@@ -112,6 +113,27 @@ asmlinkage int sys_sigaltstack(unsigned long bx)
return do_sigaltstack(uss, uoss, regs->sp);
}
+#define COPY(x) { \
+ err |= __get_user(regs->x, &sc->x); \
+}
+
+#define COPY_SEG(seg) { \
+ unsigned short tmp; \
+ err |= __get_user(tmp, &sc->seg); \
+ regs->seg = tmp; \
+}
+
+#define COPY_SEG_STRICT(seg) { \
+ unsigned short tmp; \
+ err |= __get_user(tmp, &sc->seg); \
+ regs->seg = tmp | 3; \
+}
+
+#define GET_SEG(seg) { \
+ unsigned short tmp; \
+ err |= __get_user(tmp, &sc->seg); \
+ loadsegment(seg, tmp); \
+}
/*
* Do a signal return; undo the signal stack.
@@ -120,28 +142,13 @@ static int
restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
unsigned long *pax)
{
+ void __user *buf;
+ unsigned int tmpflags;
unsigned int err = 0;
/* Always make any pending restarted system calls return -EINTR */
current_thread_info()->restart_block.fn = do_no_restart_syscall;
-#define COPY(x) err |= __get_user(regs->x, &sc->x)
-
-#define COPY_SEG(seg) \
- { unsigned short tmp; \
- err |= __get_user(tmp, &sc->seg); \
- regs->seg = tmp; }
-
-#define COPY_SEG_STRICT(seg) \
- { unsigned short tmp; \
- err |= __get_user(tmp, &sc->seg); \
- regs->seg = tmp|3; }
-
-#define GET_SEG(seg) \
- { unsigned short tmp; \
- err |= __get_user(tmp, &sc->seg); \
- loadsegment(seg, tmp); }
-
GET_SEG(gs);
COPY_SEG(fs);
COPY_SEG(es);
@@ -151,21 +158,12 @@ restore_sigcontext(struct pt_regs *regs, struct sigcontext __user *sc,
COPY_SEG_STRICT(cs);
COPY_SEG_STRICT(ss);
- {
- unsigned int tmpflags;
-
- err |= __get_user(tmpflags, &sc->flags);
- regs->flags = (regs->flags & ~FIX_EFLAGS) |
- (tmpflags & FIX_EFLAGS);
- regs->orig_ax = -1; /* disable syscall checks */
- }
-
- {
- void __user *buf;
+ err |= __get_user(tmpflags, &sc->flags);
+ regs->flags = (regs->flags & ~FIX_EFLAGS) | (tmpflags & FIX_EFLAGS);
+ regs->orig_ax = -1; /* disable syscall checks */
- err |= __get_user(buf, &sc->fpstate);
- err |= restore_i387_xstate(buf);
- }
+ err |= __get_user(buf, &sc->fpstate);
+ err |= restore_i387_xstate(buf);
err |= __get_user(*pax, &sc->ax);
return err;
@@ -214,9 +212,8 @@ badframe:
return 0;
}
-asmlinkage int sys_rt_sigreturn(unsigned long __unused)
+static long do_rt_sigreturn(struct pt_regs *regs)
{
- struct pt_regs *regs = (struct pt_regs *)&__unused;
struct rt_sigframe __user *frame;
unsigned long ax;
sigset_t set;
@@ -242,10 +239,17 @@ asmlinkage int sys_rt_sigreturn(unsigned long __unused)
return ax;
badframe:
- force_sig(SIGSEGV, current);
+ signal_fault(regs, frame, "rt_sigreturn");
return 0;
}
+asmlinkage int sys_rt_sigreturn(unsigned long __unused)
+{
+ struct pt_regs *regs = (struct pt_regs *)&__unused;
+
+ return do_rt_sigreturn(regs);
+}
+
/*
* Set up a signal frame.
*/
@@ -337,39 +341,29 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
}
static int
-setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
- struct pt_regs *regs)
+__setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
+ struct pt_regs *regs)
{
struct sigframe __user *frame;
void __user *restorer;
int err = 0;
- int usig;
void __user *fpstate = NULL;
frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
- goto give_sigsegv;
+ return -EFAULT;
- usig = current_thread_info()->exec_domain
- && current_thread_info()->exec_domain->signal_invmap
- && sig < 32
- ? current_thread_info()->exec_domain->signal_invmap[sig]
- : sig;
+ if (__put_user(sig, &frame->sig))
+ return -EFAULT;
- err = __put_user(usig, &frame->sig);
- if (err)
- goto give_sigsegv;
-
- err = setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]);
- if (err)
- goto give_sigsegv;
+ if (setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]))
+ return -EFAULT;
if (_NSIG_WORDS > 1) {
- err = __copy_to_user(&frame->extramask, &set->sig[1],
- sizeof(frame->extramask));
- if (err)
- goto give_sigsegv;
+ if (__copy_to_user(&frame->extramask, &set->sig[1],
+ sizeof(frame->extramask)))
+ return -EFAULT;
}
if (current->mm->context.vdso)
@@ -394,7 +388,7 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
err |= __put_user(0x80cd, (short __user *)(frame->retcode+6));
if (err)
- goto give_sigsegv;
+ return -EFAULT;
/* Set up registers for signal handler */
regs->sp = (unsigned long)frame;
@@ -409,38 +403,27 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
regs->cs = __USER_CS;
return 0;
-
-give_sigsegv:
- force_sigsegv(sig, current);
- return -EFAULT;
}
-static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
- sigset_t *set, struct pt_regs *regs)
+static int __setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+ sigset_t *set, struct pt_regs *regs)
{
struct rt_sigframe __user *frame;
void __user *restorer;
int err = 0;
- int usig;
void __user *fpstate = NULL;
frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
- goto give_sigsegv;
-
- usig = current_thread_info()->exec_domain
- && current_thread_info()->exec_domain->signal_invmap
- && sig < 32
- ? current_thread_info()->exec_domain->signal_invmap[sig]
- : sig;
+ return -EFAULT;
- err |= __put_user(usig, &frame->sig);
+ err |= __put_user(sig, &frame->sig);
err |= __put_user(&frame->info, &frame->pinfo);
err |= __put_user(&frame->uc, &frame->puc);
err |= copy_siginfo_to_user(&frame->info, info);
if (err)
- goto give_sigsegv;
+ return -EFAULT;
/* Create the ucontext. */
if (cpu_has_xsave)
@@ -456,7 +439,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
regs, set->sig[0]);
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
if (err)
- goto give_sigsegv;
+ return -EFAULT;
/* Set up to return from userspace. */
restorer = VDSO32_SYMBOL(current->mm->context.vdso, rt_sigreturn);
@@ -476,12 +459,12 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
err |= __put_user(0x80cd, (short __user *)(frame->retcode+5));
if (err)
- goto give_sigsegv;
+ return -EFAULT;
/* Set up registers for signal handler */
regs->sp = (unsigned long)frame;
regs->ip = (unsigned long)ka->sa.sa_handler;
- regs->ax = (unsigned long)usig;
+ regs->ax = (unsigned long)sig;
regs->dx = (unsigned long)&frame->info;
regs->cx = (unsigned long)&frame->uc;
@@ -491,15 +474,48 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
regs->cs = __USER_CS;
return 0;
-
-give_sigsegv:
- force_sigsegv(sig, current);
- return -EFAULT;
}
/*
* OK, we're invoking a handler:
*/
+static int signr_convert(int sig)
+{
+ struct thread_info *info = current_thread_info();
+
+ if (info->exec_domain && info->exec_domain->signal_invmap && sig < 32)
+ return info->exec_domain->signal_invmap[sig];
+ return sig;
+}
+
+#define is_ia32 1
+#define ia32_setup_frame __setup_frame
+#define ia32_setup_rt_frame __setup_rt_frame
+
+static int
+setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
+ sigset_t *set, struct pt_regs *regs)
+{
+ int usig = signr_convert(sig);
+ int ret;
+
+ /* Set up the stack frame */
+ if (is_ia32) {
+ if (ka->sa.sa_flags & SA_SIGINFO)
+ ret = ia32_setup_rt_frame(usig, ka, info, set, regs);
+ else
+ ret = ia32_setup_frame(usig, ka, set, regs);
+ } else
+ ret = __setup_rt_frame(sig, ka, info, set, regs);
+
+ if (ret) {
+ force_sigsegv(sig, current);
+ return -EFAULT;
+ }
+
+ return ret;
+}
+
static int
handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
sigset_t *oldset, struct pt_regs *regs)
@@ -507,9 +523,9 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
int ret;
/* Are we from a system call? */
- if ((long)regs->orig_ax >= 0) {
+ if (syscall_get_nr(current, regs) >= 0) {
/* If so, check system call restarting.. */
- switch (regs->ax) {
+ switch (syscall_get_error(current, regs)) {
case -ERESTART_RESTARTBLOCK:
case -ERESTARTNOHAND:
regs->ax = -EINTR;
@@ -536,15 +552,20 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
likely(test_and_clear_thread_flag(TIF_FORCED_TF)))
regs->flags &= ~X86_EFLAGS_TF;
- /* Set up the stack frame */
- if (ka->sa.sa_flags & SA_SIGINFO)
- ret = setup_rt_frame(sig, ka, info, oldset, regs);
- else
- ret = setup_frame(sig, ka, oldset, regs);
+ ret = setup_rt_frame(sig, ka, info, oldset, regs);
if (ret)
return ret;
+#ifdef CONFIG_X86_64
+ /*
+ * This has nothing to do with segment registers,
+ * despite the name. This magic affects uaccess.h
+ * macros' behavior. Reset it to the normal setting.
+ */
+ set_fs(USER_DS);
+#endif
+
/*
* Clear the direction flag as per the ABI for function entry.
*/
@@ -571,6 +592,7 @@ handle_signal(unsigned long sig, siginfo_t *info, struct k_sigaction *ka,
return 0;
}
+#define NR_restart_syscall __NR_restart_syscall
/*
* 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
@@ -623,9 +645,9 @@ static void do_signal(struct pt_regs *regs)
}
/* Did we come from a system call? */
- if ((long)regs->orig_ax >= 0) {
+ if (syscall_get_nr(current, regs) >= 0) {
/* Restart the system call - no handlers present */
- switch (regs->ax) {
+ switch (syscall_get_error(current, regs)) {
case -ERESTARTNOHAND:
case -ERESTARTSYS:
case -ERESTARTNOINTR:
@@ -634,7 +656,7 @@ static void do_signal(struct pt_regs *regs)
break;
case -ERESTART_RESTARTBLOCK:
- regs->ax = __NR_restart_syscall;
+ regs->ax = NR_restart_syscall;
regs->ip -= 2;
break;
}
@@ -657,6 +679,12 @@ static void do_signal(struct pt_regs *regs)
void
do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
{
+#if defined(CONFIG_X86_64) && defined(CONFIG_X86_MCE)
+ /* notify userspace of pending MCEs */
+ if (thread_info_flags & _TIF_MCE_NOTIFY)
+ mce_notify_user();
+#endif /* CONFIG_X86_64 && CONFIG_X86_MCE */
+
/* deal with pending signal delivery */
if (thread_info_flags & _TIF_SIGPENDING)
do_signal(regs);
@@ -666,5 +694,23 @@ do_notify_resume(struct pt_regs *regs, void *unused, __u32 thread_info_flags)
tracehook_notify_resume(regs);
}
+#ifdef CONFIG_X86_32
clear_thread_flag(TIF_IRET);
+#endif /* CONFIG_X86_32 */
+}
+
+void signal_fault(struct pt_regs *regs, void __user *frame, char *where)
+{
+ struct task_struct *me = current;
+
+ if (show_unhandled_signals && printk_ratelimit()) {
+ printk(KERN_INFO
+ "%s[%d] bad frame in %s frame:%p ip:%lx sp:%lx orax:%lx",
+ me->comm, me->pid, where, frame,
+ regs->ip, regs->sp, regs->orig_ax);
+ print_vma_addr(" in ", regs->ip);
+ printk(KERN_CONT "\n");
+ }
+
+ force_sig(SIGSEGV, me);
}
generated by cgit v1.2.3 (git 2.25.1) at 2025-01-15 12:08:45 +0000