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-rw-r--r--arch/x86/ia32/ia32_signal.c24
-rw-r--r--arch/x86/kernel/i387.c2
-rw-r--r--arch/x86/kernel/sigframe.h14
-rw-r--r--arch/x86/kernel/signal_32.c18
-rw-r--r--arch/x86/kernel/signal_64.c2
-rw-r--r--arch/x86/kernel/xsave.c4
6 files changed, 48 insertions, 16 deletions
diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/ia32/ia32_signal.c
index 20af4c7..a05bf0f 100644
--- a/arch/x86/ia32/ia32_signal.c
+++ b/arch/x86/ia32/ia32_signal.c
@@ -179,9 +179,10 @@ struct sigframe
u32 pretcode;
int sig;
struct sigcontext_ia32 sc;
- struct _fpstate_ia32 fpstate;
+ struct _fpstate_ia32 fpstate_unused; /* look at kernel/sigframe.h */
unsigned int extramask[_COMPAT_NSIG_WORDS-1];
char retcode[8];
+ /* fp state follows here */
};
struct rt_sigframe
@@ -192,8 +193,8 @@ struct rt_sigframe
u32 puc;
compat_siginfo_t info;
struct ucontext_ia32 uc;
- struct _fpstate_ia32 fpstate;
char retcode[8];
+ /* fp state follows here */
};
#define COPY(x) { \
@@ -402,7 +403,8 @@ static int ia32_setup_sigcontext(struct sigcontext_ia32 __user *sc,
* Determine which stack to use..
*/
static void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
- size_t frame_size)
+ size_t frame_size,
+ struct _fpstate_ia32 **fpstate)
{
unsigned long sp;
@@ -421,6 +423,11 @@ static void __user *get_sigframe(struct k_sigaction *ka, struct pt_regs *regs,
ka->sa.sa_restorer)
sp = (unsigned long) ka->sa.sa_restorer;
+ if (used_math()) {
+ sp = sp - sig_xstate_ia32_size;
+ *fpstate = (struct _fpstate_ia32 *) sp;
+ }
+
sp -= frame_size;
/* Align the stack pointer according to the i386 ABI,
* i.e. so that on function entry ((sp + 4) & 15) == 0. */
@@ -434,6 +441,7 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka,
struct sigframe __user *frame;
void __user *restorer;
int err = 0;
+ struct _fpstate_ia32 __user *fpstate = NULL;
/* copy_to_user optimizes that into a single 8 byte store */
static const struct {
@@ -448,7 +456,7 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka,
0,
};
- frame = get_sigframe(ka, regs, sizeof(*frame));
+ frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@@ -457,8 +465,7 @@ int ia32_setup_frame(int sig, struct k_sigaction *ka,
if (err)
goto give_sigsegv;
- err |= ia32_setup_sigcontext(&frame->sc, &frame->fpstate, regs,
- set->sig[0]);
+ err |= ia32_setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]);
if (err)
goto give_sigsegv;
@@ -522,6 +529,7 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
struct rt_sigframe __user *frame;
void __user *restorer;
int err = 0;
+ struct _fpstate_ia32 __user *fpstate = NULL;
/* __copy_to_user optimizes that into a single 8 byte store */
static const struct {
@@ -537,7 +545,7 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
0,
};
- frame = get_sigframe(ka, regs, sizeof(*frame));
+ frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@@ -556,7 +564,7 @@ int ia32_setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
err |= __put_user(sas_ss_flags(regs->sp),
&frame->uc.uc_stack.ss_flags);
err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
- err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
+ err |= ia32_setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
regs, set->sig[0]);
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
if (err)
diff --git a/arch/x86/kernel/i387.c b/arch/x86/kernel/i387.c
index b778e17..51fb288 100644
--- a/arch/x86/kernel/i387.c
+++ b/arch/x86/kernel/i387.c
@@ -24,6 +24,7 @@
# define save_i387_ia32 save_i387
# define restore_i387_ia32 restore_i387
# define _fpstate_ia32 _fpstate
+# define sig_xstate_ia32_size sig_xstate_size
# define user_i387_ia32_struct user_i387_struct
# define user32_fxsr_struct user_fxsr_struct
#endif
@@ -36,6 +37,7 @@
static unsigned int mxcsr_feature_mask __read_mostly = 0xffffffffu;
unsigned int xstate_size;
+unsigned int sig_xstate_ia32_size = sizeof(struct _fpstate_ia32);
static struct i387_fxsave_struct fx_scratch __cpuinitdata;
void __cpuinit mxcsr_feature_mask_init(void)
diff --git a/arch/x86/kernel/sigframe.h b/arch/x86/kernel/sigframe.h
index 72bbb51..6dd7e2b 100644
--- a/arch/x86/kernel/sigframe.h
+++ b/arch/x86/kernel/sigframe.h
@@ -3,9 +3,18 @@ struct sigframe {
char __user *pretcode;
int sig;
struct sigcontext sc;
- struct _fpstate fpstate;
+ /*
+ * fpstate is unused. fpstate is moved/allocated after
+ * retcode[] below. This movement allows to have the FP state and the
+ * future state extensions (xsave) stay together.
+ * And at the same time retaining the unused fpstate, prevents changing
+ * the offset of extramask[] in the sigframe and thus prevent any
+ * legacy application accessing/modifying it.
+ */
+ struct _fpstate fpstate_unused;
unsigned long extramask[_NSIG_WORDS-1];
char retcode[8];
+ /* fp state follows here */
};
struct rt_sigframe {
@@ -15,13 +24,14 @@ struct rt_sigframe {
void __user *puc;
struct siginfo info;
struct ucontext uc;
- struct _fpstate fpstate;
char retcode[8];
+ /* fp state follows here */
};
#else
struct rt_sigframe {
char __user *pretcode;
struct ucontext uc;
struct siginfo info;
+ /* fp state follows here */
};
#endif
diff --git a/arch/x86/kernel/signal_32.c b/arch/x86/kernel/signal_32.c
index 6fb5bcd..19a7a56 100644
--- a/arch/x86/kernel/signal_32.c
+++ b/arch/x86/kernel/signal_32.c
@@ -306,7 +306,8 @@ setup_sigcontext(struct sigcontext __user *sc, struct _fpstate __user *fpstate,
* Determine which stack to use..
*/
static inline void __user *
-get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
+get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
+ struct _fpstate **fpstate)
{
unsigned long sp;
@@ -332,6 +333,11 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size)
sp = (unsigned long) ka->sa.sa_restorer;
}
+ if (used_math()) {
+ sp = sp - sig_xstate_size;
+ *fpstate = (struct _fpstate *) sp;
+ }
+
sp -= frame_size;
/*
* Align the stack pointer according to the i386 ABI,
@@ -350,8 +356,9 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
void __user *restorer;
int err = 0;
int usig;
+ struct _fpstate __user *fpstate = NULL;
- frame = get_sigframe(ka, regs, sizeof(*frame));
+ frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@@ -366,7 +373,7 @@ setup_frame(int sig, struct k_sigaction *ka, sigset_t *set,
if (err)
goto give_sigsegv;
- err = setup_sigcontext(&frame->sc, &frame->fpstate, regs, set->sig[0]);
+ err = setup_sigcontext(&frame->sc, fpstate, regs, set->sig[0]);
if (err)
goto give_sigsegv;
@@ -427,8 +434,9 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
void __user *restorer;
int err = 0;
int usig;
+ struct _fpstate __user *fpstate = NULL;
- frame = get_sigframe(ka, regs, sizeof(*frame));
+ frame = get_sigframe(ka, regs, sizeof(*frame), &fpstate);
if (!access_ok(VERIFY_WRITE, frame, sizeof(*frame)))
goto give_sigsegv;
@@ -453,7 +461,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
err |= __put_user(sas_ss_flags(regs->sp),
&frame->uc.uc_stack.ss_flags);
err |= __put_user(current->sas_ss_size, &frame->uc.uc_stack.ss_size);
- err |= setup_sigcontext(&frame->uc.uc_mcontext, &frame->fpstate,
+ err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
regs, set->sig[0]);
err |= __copy_to_user(&frame->uc.uc_sigmask, set, sizeof(*set));
if (err)
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
index ca316b5..0deab8e 100644
--- a/arch/x86/kernel/signal_64.c
+++ b/arch/x86/kernel/signal_64.c
@@ -281,7 +281,7 @@ static int setup_rt_frame(int sig, struct k_sigaction *ka, siginfo_t *info,
struct task_struct *me = current;
if (used_math()) {
- fp = get_stack(ka, regs, sizeof(struct _fpstate));
+ fp = get_stack(ka, regs, sig_xstate_size);
frame = (void __user *)round_down(
(unsigned long)fp - sizeof(struct rt_sigframe), 16) - 8;
diff --git a/arch/x86/kernel/xsave.c b/arch/x86/kernel/xsave.c
index c68b7c4..7ad169e 100644
--- a/arch/x86/kernel/xsave.c
+++ b/arch/x86/kernel/xsave.c
@@ -17,6 +17,10 @@ unsigned int pcntxt_hmask, pcntxt_lmask;
*/
struct xsave_struct *init_xstate_buf;
+#ifdef CONFIG_X86_64
+unsigned int sig_xstate_size = sizeof(struct _fpstate);
+#endif
+
/*
* Enable the extended processor state save/restore feature
*/
generated by cgit v1.1 at 2024-10-30 13:47:03 +0000