[GIT pull] x86/misc for v6.2-rc1

From: Thomas Gleixner
Date: Mon Dec 12 2022 - 05:09:51 EST

Linus,

please pull the latest x86/misc branch from:

git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git x86-misc-2022-12-10

up to: 00ed1eabcc3b: x86/espfix: Use get_random_long() rather than archrandom

Updates for miscellaneous x86 areas:

- Reserve a new boot loader type for barebox which is usally used on ARM
and MIPS, but can also be utilized as EFI payload on x86 to provide
watchdog-supervised boot up.

- Consolidate the native and compat 32bit signal handling code and split
the 64bit version out into a separate source file

- Switch the ESPFIX random usage to get_random_long().

Thanks,

tglx

------------------>
Ahmad Fatoum (1):
Documentation/x86/boot: Reserve type_of_loader=13 for barebox

Brian Gerst (8):
x86/signal: Remove sig parameter from frame setup functions
x86/signal: Remove sigset_t parameter from frame setup functions
signal/compat: Remove compat_sigset_t override
x86: Remove __USER32_DS
x86/signal: Merge get_sigframe()
x86/signal: Add ABI prefixes to frame setup functions
x86/signal/32: Merge native and compat 32-bit signal code
x86/signal/64: Move 64-bit signal code to its own file

Jason A. Donenfeld (1):
x86/espfix: Use get_random_long() rather than archrandom


Documentation/x86/boot.rst | 1 +
arch/x86/entry/entry_64_compat.S | 4 +-
arch/x86/ia32/Makefile | 2 -
arch/x86/include/asm/elf.h | 4 -
arch/x86/include/asm/fpu/signal.h | 7 -
arch/x86/include/asm/segment.h | 2 +-
arch/x86/include/asm/sighandling.h | 9 +
arch/x86/include/asm/signal.h | 5 -
arch/x86/kernel/Makefile | 4 +-
arch/x86/kernel/espfix_64.c | 12 +-
arch/x86/kernel/signal.c | 654 +--------------------
.../x86/{ia32/ia32_signal.c => kernel/signal_32.c} | 117 ++--
arch/x86/kernel/signal_64.c | 383 ++++++++++++
arch/x86/xen/xen-asm.S | 8 +-
include/linux/compat.h | 2 -
include/linux/syscalls.h | 2 +
16 files changed, 495 insertions(+), 721 deletions(-)
rename arch/x86/{ia32/ia32_signal.c => kernel/signal_32.c} (82%)
create mode 100644 arch/x86/kernel/signal_64.c

diff --git a/Documentation/x86/boot.rst b/Documentation/x86/boot.rst
index 894a19897005..240d084782a6 100644
--- a/Documentation/x86/boot.rst
+++ b/Documentation/x86/boot.rst
@@ -455,6 +455,7 @@ Protocol: 2.00+
11 Minimal Linux Bootloader
<http://sebastian-plotz.blogspot.de>
12 OVMF UEFI virtualization stack
+ 13 barebox
== =======================================

Please contact <hpa@xxxxxxxxx> if you need a bootloader ID value assigned.
diff --git a/arch/x86/entry/entry_64_compat.S b/arch/x86/entry/entry_64_compat.S
index 4dd19819053a..59b93901660d 100644
--- a/arch/x86/entry/entry_64_compat.S
+++ b/arch/x86/entry/entry_64_compat.S
@@ -61,7 +61,7 @@ SYM_CODE_START(entry_SYSENTER_compat)
movq PER_CPU_VAR(cpu_current_top_of_stack), %rsp

/* Construct struct pt_regs on stack */
- pushq $__USER32_DS /* pt_regs->ss */
+ pushq $__USER_DS /* pt_regs->ss */
pushq $0 /* pt_regs->sp = 0 (placeholder) */

/*
@@ -197,7 +197,7 @@ SYM_INNER_LABEL(entry_SYSCALL_compat_safe_stack, SYM_L_GLOBAL)
ANNOTATE_NOENDBR

/* Construct struct pt_regs on stack */
- pushq $__USER32_DS /* pt_regs->ss */
+ pushq $__USER_DS /* pt_regs->ss */
pushq %r8 /* pt_regs->sp */
pushq %r11 /* pt_regs->flags */
pushq $__USER32_CS /* pt_regs->cs */
diff --git a/arch/x86/ia32/Makefile b/arch/x86/ia32/Makefile
index e481056698de..333556a86b2a 100644
--- a/arch/x86/ia32/Makefile
+++ b/arch/x86/ia32/Makefile
@@ -3,7 +3,5 @@
# Makefile for the ia32 kernel emulation subsystem.
#

-obj-$(CONFIG_IA32_EMULATION) := ia32_signal.o
-
audit-class-$(CONFIG_AUDIT) := audit.o
obj-$(CONFIG_IA32_EMULATION) += $(audit-class-y)
diff --git a/arch/x86/include/asm/elf.h b/arch/x86/include/asm/elf.h
index cb0ff1055ab1..be8b58da63b9 100644
--- a/arch/x86/include/asm/elf.h
+++ b/arch/x86/include/asm/elf.h
@@ -152,10 +152,6 @@ do { \
(elf_check_arch_ia32(x) || \
(IS_ENABLED(CONFIG_X86_X32_ABI) && (x)->e_machine == EM_X86_64))

-#if __USER32_DS != __USER_DS
-# error "The following code assumes __USER32_DS == __USER_DS"
-#endif
-
static inline void elf_common_init(struct thread_struct *t,
struct pt_regs *regs, const u16 ds)
{
diff --git a/arch/x86/include/asm/fpu/signal.h b/arch/x86/include/asm/fpu/signal.h
index e1c9df9102a5..611fa41711af 100644
--- a/arch/x86/include/asm/fpu/signal.h
+++ b/arch/x86/include/asm/fpu/signal.h
@@ -13,16 +13,9 @@
#ifdef CONFIG_X86_64
# include <uapi/asm/sigcontext.h>
# include <asm/user32.h>
-struct ksignal;
-int ia32_setup_rt_frame(int sig, struct ksignal *ksig,
- compat_sigset_t *set, struct pt_regs *regs);
-int ia32_setup_frame(int sig, struct ksignal *ksig,
- compat_sigset_t *set, struct pt_regs *regs);
#else
# define user_i387_ia32_struct user_i387_struct
# define user32_fxsr_struct user_fxsr_struct
-# define ia32_setup_frame __setup_frame
-# define ia32_setup_rt_frame __setup_rt_frame
#endif

extern void convert_from_fxsr(struct user_i387_ia32_struct *env,
diff --git a/arch/x86/include/asm/segment.h b/arch/x86/include/asm/segment.h
index 2e7890dd58a4..c390a672d560 100644
--- a/arch/x86/include/asm/segment.h
+++ b/arch/x86/include/asm/segment.h
@@ -135,6 +135,7 @@
#define __KERNEL_DS (GDT_ENTRY_KERNEL_DS*8)
#define __USER_DS (GDT_ENTRY_DEFAULT_USER_DS*8 + 3)
#define __USER_CS (GDT_ENTRY_DEFAULT_USER_CS*8 + 3)
+#define __USER32_CS __USER_CS
#define __ESPFIX_SS (GDT_ENTRY_ESPFIX_SS*8)

/* segment for calling fn: */
@@ -210,7 +211,6 @@
#define __KERNEL_DS (GDT_ENTRY_KERNEL_DS*8)
#define __USER32_CS (GDT_ENTRY_DEFAULT_USER32_CS*8 + 3)
#define __USER_DS (GDT_ENTRY_DEFAULT_USER_DS*8 + 3)
-#define __USER32_DS __USER_DS
#define __USER_CS (GDT_ENTRY_DEFAULT_USER_CS*8 + 3)
#define __CPUNODE_SEG (GDT_ENTRY_CPUNODE*8 + 3)

diff --git a/arch/x86/include/asm/sighandling.h b/arch/x86/include/asm/sighandling.h
index 65e667279e0f..e770c4fc47f4 100644
--- a/arch/x86/include/asm/sighandling.h
+++ b/arch/x86/include/asm/sighandling.h
@@ -15,4 +15,13 @@

void signal_fault(struct pt_regs *regs, void __user *frame, char *where);

+void __user *
+get_sigframe(struct ksignal *ksig, struct pt_regs *regs, size_t frame_size,
+ void __user **fpstate);
+
+int ia32_setup_frame(struct ksignal *ksig, struct pt_regs *regs);
+int ia32_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs);
+int x64_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs);
+int x32_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs);
+
#endif /* _ASM_X86_SIGHANDLING_H */
diff --git a/arch/x86/include/asm/signal.h b/arch/x86/include/asm/signal.h
index 2dfb5fea13af..4a4043ca6493 100644
--- a/arch/x86/include/asm/signal.h
+++ b/arch/x86/include/asm/signal.h
@@ -28,11 +28,6 @@ typedef struct {
#define SA_IA32_ABI 0x02000000u
#define SA_X32_ABI 0x01000000u

-#ifndef CONFIG_COMPAT
-#define compat_sigset_t compat_sigset_t
-typedef sigset_t compat_sigset_t;
-#endif
-
#endif /* __ASSEMBLY__ */
#include <uapi/asm/signal.h>
#ifndef __ASSEMBLY__
diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile
index f901658d9f7c..cceaafdd2d84 100644
--- a/arch/x86/kernel/Makefile
+++ b/arch/x86/kernel/Makefile
@@ -44,7 +44,7 @@ obj-y += head_$(BITS).o
obj-y += head$(BITS).o
obj-y += ebda.o
obj-y += platform-quirks.o
-obj-y += process_$(BITS).o signal.o
+obj-y += process_$(BITS).o signal.o signal_$(BITS).o
obj-$(CONFIG_COMPAT) += signal_compat.o
obj-y += traps.o idt.o irq.o irq_$(BITS).o dumpstack_$(BITS).o
obj-y += time.o ioport.o dumpstack.o nmi.o
@@ -54,7 +54,7 @@ obj-$(CONFIG_JUMP_LABEL) += jump_label.o
obj-$(CONFIG_IRQ_WORK) += irq_work.o
obj-y += probe_roms.o
obj-$(CONFIG_X86_32) += sys_ia32.o
-obj-$(CONFIG_IA32_EMULATION) += sys_ia32.o
+obj-$(CONFIG_IA32_EMULATION) += sys_ia32.o signal_32.o
obj-$(CONFIG_X86_64) += sys_x86_64.o
obj-$(CONFIG_X86_ESPFIX64) += espfix_64.o
obj-$(CONFIG_SYSFS) += ksysfs.o
diff --git a/arch/x86/kernel/espfix_64.c b/arch/x86/kernel/espfix_64.c
index 9417d5aa7305..16f9814c9be0 100644
--- a/arch/x86/kernel/espfix_64.c
+++ b/arch/x86/kernel/espfix_64.c
@@ -94,17 +94,7 @@ static inline unsigned long espfix_base_addr(unsigned int cpu)

static void init_espfix_random(void)
{
- unsigned long rand;
-
- /*
- * This is run before the entropy pools are initialized,
- * but this is hopefully better than nothing.
- */
- if (!arch_get_random_longs(&rand, 1)) {
- /* The constant is an arbitrary large prime */
- rand = rdtsc();
- rand *= 0xc345c6b72fd16123UL;
- }
+ unsigned long rand = get_random_long();

slot_random = rand % ESPFIX_STACKS_PER_PAGE;
page_random = (rand / ESPFIX_STACKS_PER_PAGE)
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 9c7265b524c7..1504eb8d25aa 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -37,180 +37,27 @@
#include <asm/sighandling.h>
#include <asm/vm86.h>

-#ifdef CONFIG_X86_64
-#include <linux/compat.h>
-#include <asm/proto.h>
-#include <asm/ia32_unistd.h>
-#include <asm/fpu/xstate.h>
-#endif /* CONFIG_X86_64 */
-
#include <asm/syscall.h>
#include <asm/sigframe.h>
#include <asm/signal.h>

-#ifdef CONFIG_X86_64
-/*
- * If regs->ss will cause an IRET fault, change it. Otherwise leave it
- * alone. Using this generally makes no sense unless
- * user_64bit_mode(regs) would return true.
- */
-static void force_valid_ss(struct pt_regs *regs)
+static inline int is_ia32_compat_frame(struct ksignal *ksig)
{
- u32 ar;
- asm volatile ("lar %[old_ss], %[ar]\n\t"
- "jz 1f\n\t" /* If invalid: */
- "xorl %[ar], %[ar]\n\t" /* set ar = 0 */
- "1:"
- : [ar] "=r" (ar)
- : [old_ss] "rm" ((u16)regs->ss));
-
- /*
- * For a valid 64-bit user context, we need DPL 3, type
- * read-write data or read-write exp-down data, and S and P
- * set. We can't use VERW because VERW doesn't check the
- * P bit.
- */
- ar &= AR_DPL_MASK | AR_S | AR_P | AR_TYPE_MASK;
- if (ar != (AR_DPL3 | AR_S | AR_P | AR_TYPE_RWDATA) &&
- ar != (AR_DPL3 | AR_S | AR_P | AR_TYPE_RWDATA_EXPDOWN))
- regs->ss = __USER_DS;
+ return IS_ENABLED(CONFIG_IA32_EMULATION) &&
+ ksig->ka.sa.sa_flags & SA_IA32_ABI;
}
-# define CONTEXT_COPY_SIZE offsetof(struct sigcontext, reserved1)
-#else
-# define CONTEXT_COPY_SIZE sizeof(struct sigcontext)
-#endif

-static bool restore_sigcontext(struct pt_regs *regs,
- struct sigcontext __user *usc,
- unsigned long uc_flags)
+static inline int is_ia32_frame(struct ksignal *ksig)
{
- struct sigcontext sc;
-
- /* Always make any pending restarted system calls return -EINTR */
- current->restart_block.fn = do_no_restart_syscall;
-
- if (copy_from_user(&sc, usc, CONTEXT_COPY_SIZE))
- return false;
-
-#ifdef CONFIG_X86_32
- loadsegment(gs, sc.gs);
- regs->fs = sc.fs;
- regs->es = sc.es;
- regs->ds = sc.ds;
-#endif /* CONFIG_X86_32 */
-
- regs->bx = sc.bx;
- regs->cx = sc.cx;
- regs->dx = sc.dx;
- regs->si = sc.si;
- regs->di = sc.di;
- regs->bp = sc.bp;
- regs->ax = sc.ax;
- regs->sp = sc.sp;
- regs->ip = sc.ip;
-
-#ifdef CONFIG_X86_64
- regs->r8 = sc.r8;
- regs->r9 = sc.r9;
- regs->r10 = sc.r10;
- regs->r11 = sc.r11;
- regs->r12 = sc.r12;
- regs->r13 = sc.r13;
- regs->r14 = sc.r14;
- regs->r15 = sc.r15;
-#endif /* CONFIG_X86_64 */
-
- /* Get CS/SS and force CPL3 */
- regs->cs = sc.cs | 0x03;
- regs->ss = sc.ss | 0x03;
-
- regs->flags = (regs->flags & ~FIX_EFLAGS) | (sc.flags & FIX_EFLAGS);
- /* disable syscall checks */
- regs->orig_ax = -1;
-
-#ifdef CONFIG_X86_64
- /*
- * Fix up SS if needed for the benefit of old DOSEMU and
- * CRIU.
- */
- if (unlikely(!(uc_flags & UC_STRICT_RESTORE_SS) && user_64bit_mode(regs)))
- force_valid_ss(regs);
-#endif
-
- return fpu__restore_sig((void __user *)sc.fpstate,
- IS_ENABLED(CONFIG_X86_32));
+ return IS_ENABLED(CONFIG_X86_32) || is_ia32_compat_frame(ksig);
}

-static __always_inline int
-__unsafe_setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate,
- struct pt_regs *regs, unsigned long mask)
+static inline int is_x32_frame(struct ksignal *ksig)
{
-#ifdef CONFIG_X86_32
- unsigned int gs;
- savesegment(gs, gs);
-
- unsafe_put_user(gs, (unsigned int __user *)&sc->gs, Efault);
- unsafe_put_user(regs->fs, (unsigned int __user *)&sc->fs, Efault);
- unsafe_put_user(regs->es, (unsigned int __user *)&sc->es, Efault);
- unsafe_put_user(regs->ds, (unsigned int __user *)&sc->ds, Efault);
-#endif /* CONFIG_X86_32 */
-
- unsafe_put_user(regs->di, &sc->di, Efault);
- unsafe_put_user(regs->si, &sc->si, Efault);
- unsafe_put_user(regs->bp, &sc->bp, Efault);
- unsafe_put_user(regs->sp, &sc->sp, Efault);
- unsafe_put_user(regs->bx, &sc->bx, Efault);
- unsafe_put_user(regs->dx, &sc->dx, Efault);
- unsafe_put_user(regs->cx, &sc->cx, Efault);
- unsafe_put_user(regs->ax, &sc->ax, Efault);
-#ifdef CONFIG_X86_64
- unsafe_put_user(regs->r8, &sc->r8, Efault);
- unsafe_put_user(regs->r9, &sc->r9, Efault);
- unsafe_put_user(regs->r10, &sc->r10, Efault);
- unsafe_put_user(regs->r11, &sc->r11, Efault);
- unsafe_put_user(regs->r12, &sc->r12, Efault);
- unsafe_put_user(regs->r13, &sc->r13, Efault);
- unsafe_put_user(regs->r14, &sc->r14, Efault);
- unsafe_put_user(regs->r15, &sc->r15, Efault);
-#endif /* CONFIG_X86_64 */
-
- unsafe_put_user(current->thread.trap_nr, &sc->trapno, Efault);
- unsafe_put_user(current->thread.error_code, &sc->err, Efault);
- unsafe_put_user(regs->ip, &sc->ip, Efault);
-#ifdef CONFIG_X86_32
- unsafe_put_user(regs->cs, (unsigned int __user *)&sc->cs, Efault);
- unsafe_put_user(regs->flags, &sc->flags, Efault);
- unsafe_put_user(regs->sp, &sc->sp_at_signal, Efault);
- unsafe_put_user(regs->ss, (unsigned int __user *)&sc->ss, Efault);
-#else /* !CONFIG_X86_32 */
- unsafe_put_user(regs->flags, &sc->flags, Efault);
- unsafe_put_user(regs->cs, &sc->cs, Efault);
- unsafe_put_user(0, &sc->gs, Efault);
- unsafe_put_user(0, &sc->fs, Efault);
- unsafe_put_user(regs->ss, &sc->ss, Efault);
-#endif /* CONFIG_X86_32 */
-
- unsafe_put_user(fpstate, (unsigned long __user *)&sc->fpstate, Efault);
-
- /* non-iBCS2 extensions.. */
- unsafe_put_user(mask, &sc->oldmask, Efault);
- unsafe_put_user(current->thread.cr2, &sc->cr2, Efault);
- return 0;
-Efault:
- return -EFAULT;
+ return IS_ENABLED(CONFIG_X86_X32_ABI) &&
+ ksig->ka.sa.sa_flags & SA_X32_ABI;
}

-#define unsafe_put_sigcontext(sc, fp, regs, set, label) \
-do { \
- if (__unsafe_setup_sigcontext(sc, fp, regs, set->sig[0])) \
- goto label; \
-} while(0);
-
-#define unsafe_put_sigmask(set, frame, label) \
- unsafe_put_user(*(__u64 *)(set), \
- (__u64 __user *)&(frame)->uc.uc_sigmask, \
- label)
-
/*
* Set up a signal frame.
*/
@@ -223,24 +70,12 @@ do { \
/*
* Determine which stack to use..
*/
-static unsigned long align_sigframe(unsigned long sp)
-{
-#ifdef CONFIG_X86_32
- /*
- * Align the stack pointer according to the i386 ABI,
- * i.e. so that on function entry ((sp + 4) & 15) == 0.
- */
- sp = ((sp + 4) & -FRAME_ALIGNMENT) - 4;
-#else /* !CONFIG_X86_32 */
- sp = round_down(sp, FRAME_ALIGNMENT) - 8;
-#endif
- return sp;
-}
-
-static void __user *
-get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
+void __user *
+get_sigframe(struct ksignal *ksig, struct pt_regs *regs, size_t frame_size,
void __user **fpstate)
{
+ struct k_sigaction *ka = &ksig->ka;
+ int ia32_frame = is_ia32_frame(ksig);
/* Default to using normal stack */
bool nested_altstack = on_sig_stack(regs->sp);
bool entering_altstack = false;
@@ -249,7 +84,7 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
unsigned long buf_fx = 0;

/* redzone */
- if (IS_ENABLED(CONFIG_X86_64))
+ if (!ia32_frame)
sp -= 128;

/* This is the X/Open sanctioned signal stack switching. */
@@ -263,7 +98,7 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
sp = current->sas_ss_sp + current->sas_ss_size;
entering_altstack = true;
}
- } else if (IS_ENABLED(CONFIG_X86_32) &&
+ } else if (ia32_frame &&
!nested_altstack &&
regs->ss != __USER_DS &&
!(ka->sa.sa_flags & SA_RESTORER) &&
@@ -273,11 +108,19 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
entering_altstack = true;
}

- sp = fpu__alloc_mathframe(sp, IS_ENABLED(CONFIG_X86_32),
- &buf_fx, &math_size);
+ sp = fpu__alloc_mathframe(sp, ia32_frame, &buf_fx, &math_size);
*fpstate = (void __user *)sp;

- sp = align_sigframe(sp - frame_size);
+ sp -= frame_size;
+
+ if (ia32_frame)
+ /*
+ * Align the stack pointer according to the i386 ABI,
+ * i.e. so that on function entry ((sp + 4) & 15) == 0.
+ */
+ sp = ((sp + 4) & -FRAME_ALIGNMENT) - 4;
+ else
+ sp = round_down(sp, FRAME_ALIGNMENT) - 8;

/*
* If we are on the alternate signal stack and would overflow it, don't.
@@ -300,391 +143,6 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs *regs, size_t frame_size,
return (void __user *)sp;
}

-#ifdef CONFIG_X86_32
-static const struct {
- u16 poplmovl;
- u32 val;
- u16 int80;
-} __attribute__((packed)) retcode = {
- 0xb858, /* popl %eax; movl $..., %eax */
- __NR_sigreturn,
- 0x80cd, /* int $0x80 */
-};
-
-static const struct {
- u8 movl;
- u32 val;
- u16 int80;
- u8 pad;
-} __attribute__((packed)) rt_retcode = {
- 0xb8, /* movl $..., %eax */
- __NR_rt_sigreturn,
- 0x80cd, /* int $0x80 */
- 0
-};
-
-static int
-__setup_frame(int sig, struct ksignal *ksig, sigset_t *set,
- struct pt_regs *regs)
-{
- struct sigframe __user *frame;
- void __user *restorer;
- void __user *fp = NULL;
-
- frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fp);
-
- if (!user_access_begin(frame, sizeof(*frame)))
- return -EFAULT;
-
- unsafe_put_user(sig, &frame->sig, Efault);
- unsafe_put_sigcontext(&frame->sc, fp, regs, set, Efault);
- unsafe_put_user(set->sig[1], &frame->extramask[0], Efault);
- if (current->mm->context.vdso)
- restorer = current->mm->context.vdso +
- vdso_image_32.sym___kernel_sigreturn;
- else
- restorer = &frame->retcode;
- if (ksig->ka.sa.sa_flags & SA_RESTORER)
- restorer = ksig->ka.sa.sa_restorer;
-
- /* Set up to return from userspace. */
- unsafe_put_user(restorer, &frame->pretcode, Efault);
-
- /*
- * This is popl %eax ; movl $__NR_sigreturn, %eax ; int $0x80
- *
- * WE DO NOT USE IT ANY MORE! It's only left here for historical
- * reasons and because gdb uses it as a signature to notice
- * signal handler stack frames.
- */
- unsafe_put_user(*((u64 *)&retcode), (u64 *)frame->retcode, Efault);
- user_access_end();
-
- /* Set up registers for signal handler */
- regs->sp = (unsigned long)frame;
- regs->ip = (unsigned long)ksig->ka.sa.sa_handler;
- regs->ax = (unsigned long)sig;
- regs->dx = 0;
- regs->cx = 0;
-
- regs->ds = __USER_DS;
- regs->es = __USER_DS;
- regs->ss = __USER_DS;
- regs->cs = __USER_CS;
-
- return 0;
-
-Efault:
- user_access_end();
- return -EFAULT;
-}
-
-static int __setup_rt_frame(int sig, struct ksignal *ksig,
- sigset_t *set, struct pt_regs *regs)
-{
- struct rt_sigframe __user *frame;
- void __user *restorer;
- void __user *fp = NULL;
-
- frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fp);
-
- if (!user_access_begin(frame, sizeof(*frame)))
- return -EFAULT;
-
- unsafe_put_user(sig, &frame->sig, Efault);
- unsafe_put_user(&frame->info, &frame->pinfo, Efault);
- unsafe_put_user(&frame->uc, &frame->puc, Efault);
-
- /* Create the ucontext. */
- if (static_cpu_has(X86_FEATURE_XSAVE))
- unsafe_put_user(UC_FP_XSTATE, &frame->uc.uc_flags, Efault);
- else
- unsafe_put_user(0, &frame->uc.uc_flags, Efault);
- unsafe_put_user(0, &frame->uc.uc_link, Efault);
- unsafe_save_altstack(&frame->uc.uc_stack, regs->sp, Efault);
-
- /* Set up to return from userspace. */
- restorer = current->mm->context.vdso +
- vdso_image_32.sym___kernel_rt_sigreturn;
- if (ksig->ka.sa.sa_flags & SA_RESTORER)
- restorer = ksig->ka.sa.sa_restorer;
- unsafe_put_user(restorer, &frame->pretcode, Efault);
-
- /*
- * This is movl $__NR_rt_sigreturn, %ax ; int $0x80
- *
- * WE DO NOT USE IT ANY MORE! It's only left here for historical
- * reasons and because gdb uses it as a signature to notice
- * signal handler stack frames.
- */
- unsafe_put_user(*((u64 *)&rt_retcode), (u64 *)frame->retcode, Efault);
- unsafe_put_sigcontext(&frame->uc.uc_mcontext, fp, regs, set, Efault);
- unsafe_put_sigmask(set, frame, Efault);
- user_access_end();
-
- if (copy_siginfo_to_user(&frame->info, &ksig->info))
- return -EFAULT;
-
- /* Set up registers for signal handler */
- regs->sp = (unsigned long)frame;
- regs->ip = (unsigned long)ksig->ka.sa.sa_handler;
- regs->ax = (unsigned long)sig;
- regs->dx = (unsigned long)&frame->info;
- regs->cx = (unsigned long)&frame->uc;
-
- regs->ds = __USER_DS;
- regs->es = __USER_DS;
- regs->ss = __USER_DS;
- regs->cs = __USER_CS;
-
- return 0;
-Efault:
- user_access_end();
- return -EFAULT;
-}
-#else /* !CONFIG_X86_32 */
-static unsigned long frame_uc_flags(struct pt_regs *regs)
-{
- unsigned long flags;
-
- if (boot_cpu_has(X86_FEATURE_XSAVE))
- flags = UC_FP_XSTATE | UC_SIGCONTEXT_SS;
- else
- flags = UC_SIGCONTEXT_SS;
-
- if (likely(user_64bit_mode(regs)))
- flags |= UC_STRICT_RESTORE_SS;
-
- return flags;
-}
-
-static int __setup_rt_frame(int sig, struct ksignal *ksig,
- sigset_t *set, struct pt_regs *regs)
-{
- struct rt_sigframe __user *frame;
- void __user *fp = NULL;
- unsigned long uc_flags;
-
- /* x86-64 should always use SA_RESTORER. */
- if (!(ksig->ka.sa.sa_flags & SA_RESTORER))
- return -EFAULT;
-
- frame = get_sigframe(&ksig->ka, regs, sizeof(struct rt_sigframe), &fp);
- uc_flags = frame_uc_flags(regs);
-
- if (!user_access_begin(frame, sizeof(*frame)))
- return -EFAULT;
-
- /* Create the ucontext. */
- unsafe_put_user(uc_flags, &frame->uc.uc_flags, Efault);
- unsafe_put_user(0, &frame->uc.uc_link, Efault);
- unsafe_save_altstack(&frame->uc.uc_stack, regs->sp, Efault);
-
- /* Set up to return from userspace. If provided, use a stub
- already in userspace. */
- unsafe_put_user(ksig->ka.sa.sa_restorer, &frame->pretcode, Efault);
- unsafe_put_sigcontext(&frame->uc.uc_mcontext, fp, regs, set, Efault);
- unsafe_put_sigmask(set, frame, Efault);
- user_access_end();
-
- if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
- if (copy_siginfo_to_user(&frame->info, &ksig->info))
- return -EFAULT;
- }
-
- /* Set up registers for signal handler */
- regs->di = sig;
- /* In case the signal handler was declared without prototypes */
- regs->ax = 0;
-
- /* This also works for non SA_SIGINFO handlers because they expect the
- next argument after the signal number on the stack. */
- regs->si = (unsigned long)&frame->info;
- regs->dx = (unsigned long)&frame->uc;
- regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
-
- regs->sp = (unsigned long)frame;
-
- /*
- * Set up the CS and SS registers to run signal handlers in
- * 64-bit mode, even if the handler happens to be interrupting
- * 32-bit or 16-bit code.
- *
- * SS is subtle. In 64-bit mode, we don't need any particular
- * SS descriptor, but we do need SS to be valid. It's possible
- * that the old SS is entirely bogus -- this can happen if the
- * signal we're trying to deliver is #GP or #SS caused by a bad
- * SS value. We also have a compatibility issue here: DOSEMU
- * relies on the contents of the SS register indicating the
- * SS value at the time of the signal, even though that code in
- * DOSEMU predates sigreturn's ability to restore SS. (DOSEMU
- * avoids relying on sigreturn to restore SS; instead it uses
- * a trampoline.) So we do our best: if the old SS was valid,
- * we keep it. Otherwise we replace it.
- */
- regs->cs = __USER_CS;
-
- if (unlikely(regs->ss != __USER_DS))
- force_valid_ss(regs);
-
- return 0;
-
-Efault:
- user_access_end();
- return -EFAULT;
-}
-#endif /* CONFIG_X86_32 */
-
-#ifdef CONFIG_X86_X32_ABI
-static int x32_copy_siginfo_to_user(struct compat_siginfo __user *to,
- const struct kernel_siginfo *from)
-{
- struct compat_siginfo new;
-
- copy_siginfo_to_external32(&new, from);
- if (from->si_signo == SIGCHLD) {
- new._sifields._sigchld_x32._utime = from->si_utime;
- new._sifields._sigchld_x32._stime = from->si_stime;
- }
- if (copy_to_user(to, &new, sizeof(struct compat_siginfo)))
- return -EFAULT;
- return 0;
-}
-
-int copy_siginfo_to_user32(struct compat_siginfo __user *to,
- const struct kernel_siginfo *from)
-{
- if (in_x32_syscall())
- return x32_copy_siginfo_to_user(to, from);
- return __copy_siginfo_to_user32(to, from);
-}
-#endif /* CONFIG_X86_X32_ABI */
-
-static int x32_setup_rt_frame(struct ksignal *ksig,
- compat_sigset_t *set,
- struct pt_regs *regs)
-{
-#ifdef CONFIG_X86_X32_ABI
- struct rt_sigframe_x32 __user *frame;
- unsigned long uc_flags;
- void __user *restorer;
- void __user *fp = NULL;
-
- if (!(ksig->ka.sa.sa_flags & SA_RESTORER))
- return -EFAULT;
-
- frame = get_sigframe(&ksig->ka, regs, sizeof(*frame), &fp);
-
- uc_flags = frame_uc_flags(regs);
-
- if (!user_access_begin(frame, sizeof(*frame)))
- return -EFAULT;
-
- /* Create the ucontext. */
- unsafe_put_user(uc_flags, &frame->uc.uc_flags, Efault);
- unsafe_put_user(0, &frame->uc.uc_link, Efault);
- unsafe_compat_save_altstack(&frame->uc.uc_stack, regs->sp, Efault);
- unsafe_put_user(0, &frame->uc.uc__pad0, Efault);
- restorer = ksig->ka.sa.sa_restorer;
- unsafe_put_user(restorer, (unsigned long __user *)&frame->pretcode, Efault);
- unsafe_put_sigcontext(&frame->uc.uc_mcontext, fp, regs, set, Efault);
- unsafe_put_sigmask(set, frame, Efault);
- user_access_end();
-
- if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
- if (x32_copy_siginfo_to_user(&frame->info, &ksig->info))
- return -EFAULT;
- }
-
- /* Set up registers for signal handler */
- regs->sp = (unsigned long) frame;
- regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
-
- /* We use the x32 calling convention here... */
- regs->di = ksig->sig;
- regs->si = (unsigned long) &frame->info;
- regs->dx = (unsigned long) &frame->uc;
-
- loadsegment(ds, __USER_DS);
- loadsegment(es, __USER_DS);
-
- regs->cs = __USER_CS;
- regs->ss = __USER_DS;
-#endif /* CONFIG_X86_X32_ABI */
-
- return 0;
-#ifdef CONFIG_X86_X32_ABI
-Efault:
- user_access_end();
- return -EFAULT;
-#endif
-}
-
-/*
- * Do a signal return; undo the signal stack.
- */
-#ifdef CONFIG_X86_32
-SYSCALL_DEFINE0(sigreturn)
-{
- struct pt_regs *regs = current_pt_regs();
- struct sigframe __user *frame;
- sigset_t set;
-
- frame = (struct sigframe __user *)(regs->sp - 8);
-
- if (!access_ok(frame, sizeof(*frame)))
- goto badframe;
- if (__get_user(set.sig[0], &frame->sc.oldmask) ||
- __get_user(set.sig[1], &frame->extramask[0]))
- goto badframe;
-
- set_current_blocked(&set);
-
- /*
- * x86_32 has no uc_flags bits relevant to restore_sigcontext.
- * Save a few cycles by skipping the __get_user.
- */
- if (!restore_sigcontext(regs, &frame->sc, 0))
- goto badframe;
- return regs->ax;
-
-badframe:
- signal_fault(regs, frame, "sigreturn");
-
- return 0;
-}
-#endif /* CONFIG_X86_32 */
-
-SYSCALL_DEFINE0(rt_sigreturn)
-{
- struct pt_regs *regs = current_pt_regs();
- struct rt_sigframe __user *frame;
- sigset_t set;
- unsigned long uc_flags;
-
- frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long));
- if (!access_ok(frame, sizeof(*frame)))
- goto badframe;
- if (__get_user(*(__u64 *)&set, (__u64 __user *)&frame->uc.uc_sigmask))
- goto badframe;
- if (__get_user(uc_flags, &frame->uc.uc_flags))
- goto badframe;
-
- set_current_blocked(&set);
-
- if (!restore_sigcontext(regs, &frame->uc.uc_mcontext, uc_flags))
- goto badframe;
-
- if (restore_altstack(&frame->uc.uc_stack))
- goto badframe;
-
- return regs->ax;
-
-badframe:
- signal_fault(regs, frame, "rt_sigreturn");
- return 0;
-}
-
/*
* There are four different struct types for signal frame: sigframe_ia32,
* rt_sigframe_ia32, rt_sigframe_x32, and rt_sigframe. Use the worst case
@@ -743,43 +201,22 @@ unsigned long get_sigframe_size(void)
return max_frame_size;
}

-static inline int is_ia32_compat_frame(struct ksignal *ksig)
-{
- return IS_ENABLED(CONFIG_IA32_EMULATION) &&
- ksig->ka.sa.sa_flags & SA_IA32_ABI;
-}
-
-static inline int is_ia32_frame(struct ksignal *ksig)
-{
- return IS_ENABLED(CONFIG_X86_32) || is_ia32_compat_frame(ksig);
-}
-
-static inline int is_x32_frame(struct ksignal *ksig)
-{
- return IS_ENABLED(CONFIG_X86_X32_ABI) &&
- ksig->ka.sa.sa_flags & SA_X32_ABI;
-}
-
static int
setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
{
- int usig = ksig->sig;
- sigset_t *set = sigmask_to_save();
- compat_sigset_t *cset = (compat_sigset_t *) set;
-
/* Perform fixup for the pre-signal frame. */
rseq_signal_deliver(ksig, regs);

/* Set up the stack frame */
if (is_ia32_frame(ksig)) {
if (ksig->ka.sa.sa_flags & SA_SIGINFO)
- return ia32_setup_rt_frame(usig, ksig, cset, regs);
+ return ia32_setup_rt_frame(ksig, regs);
else
- return ia32_setup_frame(usig, ksig, cset, regs);
+ return ia32_setup_frame(ksig, regs);
} else if (is_x32_frame(ksig)) {
- return x32_setup_rt_frame(ksig, cset, regs);
+ return x32_setup_rt_frame(ksig, regs);
} else {
- return __setup_rt_frame(ksig->sig, ksig, set, regs);
+ return x64_setup_rt_frame(ksig, regs);
}
}

@@ -969,36 +406,3 @@ bool sigaltstack_size_valid(size_t ss_size)
return true;
}
#endif /* CONFIG_DYNAMIC_SIGFRAME */
-
-#ifdef CONFIG_X86_X32_ABI
-COMPAT_SYSCALL_DEFINE0(x32_rt_sigreturn)
-{
- struct pt_regs *regs = current_pt_regs();
- struct rt_sigframe_x32 __user *frame;
- sigset_t set;
- unsigned long uc_flags;
-
- frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8);
-
- if (!access_ok(frame, sizeof(*frame)))
- goto badframe;
- if (__get_user(set.sig[0], (__u64 __user *)&frame->uc.uc_sigmask))
- goto badframe;
- if (__get_user(uc_flags, &frame->uc.uc_flags))
- goto badframe;
-
- set_current_blocked(&set);
-
- if (!restore_sigcontext(regs, &frame->uc.uc_mcontext, uc_flags))
- goto badframe;
-
- if (compat_restore_altstack(&frame->uc.uc_stack))
- goto badframe;
-
- return regs->ax;
-
-badframe:
- signal_fault(regs, frame, "x32 rt_sigreturn");
- return 0;
-}
-#endif
diff --git a/arch/x86/ia32/ia32_signal.c b/arch/x86/kernel/signal_32.c
similarity index 82%
rename from arch/x86/ia32/ia32_signal.c
rename to arch/x86/kernel/signal_32.c
index c9c3859322fa..2553136cf39b 100644
--- a/arch/x86/ia32/ia32_signal.c
+++ b/arch/x86/kernel/signal_32.c
@@ -1,7 +1,5 @@
// SPDX-License-Identifier: GPL-2.0
/*
- * linux/arch/x86_64/ia32/ia32_signal.c
- *
* Copyright (C) 1991, 1992 Linus Torvalds
*
* 1997-11-28 Modified for POSIX.1b signals by Richard Henderson
@@ -26,7 +24,6 @@
#include <linux/uaccess.h>
#include <asm/fpu/signal.h>
#include <asm/ptrace.h>
-#include <asm/ia32_unistd.h>
#include <asm/user32.h>
#include <uapi/asm/sigcontext.h>
#include <asm/proto.h>
@@ -35,6 +32,9 @@
#include <asm/sighandling.h>
#include <asm/smap.h>

+#ifdef CONFIG_IA32_EMULATION
+#include <asm/ia32_unistd.h>
+
static inline void reload_segments(struct sigcontext_32 *sc)
{
unsigned int cur;
@@ -53,6 +53,21 @@ static inline void reload_segments(struct sigcontext_32 *sc)
loadsegment(es, sc->es | 0x03);
}

+#define sigset32_t compat_sigset_t
+#define restore_altstack32 compat_restore_altstack
+#define unsafe_save_altstack32 unsafe_compat_save_altstack
+
+#else
+
+#define sigset32_t sigset_t
+#define __NR_ia32_sigreturn __NR_sigreturn
+#define __NR_ia32_rt_sigreturn __NR_rt_sigreturn
+#define restore_altstack32 restore_altstack
+#define unsafe_save_altstack32 unsafe_save_altstack
+#define __copy_siginfo_to_user32 copy_siginfo_to_user
+
+#endif
+
/*
* Do a signal return; undo the signal stack.
*/
@@ -86,6 +101,7 @@ static bool ia32_restore_sigcontext(struct pt_regs *regs,
/* disable syscall checks */
regs->orig_ax = -1;

+#ifdef CONFIG_IA32_EMULATION
/*
* Reload fs and gs if they have changed in the signal
* handler. This does not handle long fs/gs base changes in
@@ -93,10 +109,17 @@ static bool ia32_restore_sigcontext(struct pt_regs *regs,
* normal case.
*/
reload_segments(&sc);
+#else
+ loadsegment(gs, sc.gs);
+ regs->fs = sc.fs;
+ regs->es = sc.es;
+ regs->ds = sc.ds;
+#endif
+
return fpu__restore_sig(compat_ptr(sc.fpstate), 1);
}

-COMPAT_SYSCALL_DEFINE0(sigreturn)
+SYSCALL32_DEFINE0(sigreturn)
{
struct pt_regs *regs = current_pt_regs();
struct sigframe_ia32 __user *frame = (struct sigframe_ia32 __user *)(regs->sp-8);
@@ -119,7 +142,7 @@ COMPAT_SYSCALL_DEFINE0(sigreturn)
return 0;
}

-COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
+SYSCALL32_DEFINE0(rt_sigreturn)
{
struct pt_regs *regs = current_pt_regs();
struct rt_sigframe_ia32 __user *frame;
@@ -129,7 +152,7 @@ COMPAT_SYSCALL_DEFINE0(rt_sigreturn)

if (!access_ok(frame, sizeof(*frame)))
goto badframe;
- if (__get_user(set.sig[0], (__u64 __user *)&frame->uc.uc_sigmask))
+ if (__get_user(*(__u64 *)&set, (__u64 __user *)&frame->uc.uc_sigmask))
goto badframe;

set_current_blocked(&set);
@@ -137,7 +160,7 @@ COMPAT_SYSCALL_DEFINE0(rt_sigreturn)
if (!ia32_restore_sigcontext(regs, &frame->uc.uc_mcontext))
goto badframe;

- if (compat_restore_altstack(&frame->uc.uc_stack))
+ if (restore_altstack32(&frame->uc.uc_stack))
goto badframe;

return regs->ax;
@@ -159,9 +182,15 @@ __unsafe_setup_sigcontext32(struct sigcontext_32 __user *sc,
struct pt_regs *regs, unsigned int mask)
{
unsafe_put_user(get_user_seg(gs), (unsigned int __user *)&sc->gs, Efault);
+#ifdef CONFIG_IA32_EMULATION
unsafe_put_user(get_user_seg(fs), (unsigned int __user *)&sc->fs, Efault);
unsafe_put_user(get_user_seg(ds), (unsigned int __user *)&sc->ds, Efault);
unsafe_put_user(get_user_seg(es), (unsigned int __user *)&sc->es, Efault);
+#else
+ unsafe_put_user(regs->fs, (unsigned int __user *)&sc->fs, Efault);
+ unsafe_put_user(regs->es, (unsigned int __user *)&sc->es, Efault);
+ unsafe_put_user(regs->ds, (unsigned int __user *)&sc->ds, Efault);
+#endif

unsafe_put_user(regs->di, &sc->di, Efault);
unsafe_put_user(regs->si, &sc->si, Efault);
@@ -196,43 +225,9 @@ do { \
goto label; \
} while(0)

-/*
- * Determine which stack to use..
- */
-static void __user *get_sigframe(struct ksignal *ksig, struct pt_regs *regs,
- size_t frame_size,
- void __user **fpstate)
-{
- unsigned long sp, fx_aligned, math_size;
-
- /* Default to using normal stack */
- sp = regs->sp;
-
- /* This is the X/Open sanctioned signal stack switching. */
- if (ksig->ka.sa.sa_flags & SA_ONSTACK)
- sp = sigsp(sp, ksig);
- /* This is the legacy signal stack switching. */
- else if (regs->ss != __USER32_DS &&
- !(ksig->ka.sa.sa_flags & SA_RESTORER) &&
- ksig->ka.sa.sa_restorer)
- sp = (unsigned long) ksig->ka.sa.sa_restorer;
-
- sp = fpu__alloc_mathframe(sp, 1, &fx_aligned, &math_size);
- *fpstate = (struct _fpstate_32 __user *) sp;
- if (!copy_fpstate_to_sigframe(*fpstate, (void __user *)fx_aligned,
- math_size))
- return (void __user *) -1L;
-
- sp -= frame_size;
- /* Align the stack pointer according to the i386 ABI,
- * i.e. so that on function entry ((sp + 4) & 15) == 0. */
- sp = ((sp + 4) & -16ul) - 4;
- return (void __user *) sp;
-}
-
-int ia32_setup_frame(int sig, struct ksignal *ksig,
- compat_sigset_t *set, struct pt_regs *regs)
+int ia32_setup_frame(struct ksignal *ksig, struct pt_regs *regs)
{
+ sigset32_t *set = (sigset32_t *) sigmask_to_save();
struct sigframe_ia32 __user *frame;
void __user *restorer;
void __user *fp = NULL;
@@ -264,7 +259,7 @@ int ia32_setup_frame(int sig, struct ksignal *ksig,
if (!user_access_begin(frame, sizeof(*frame)))
return -EFAULT;

- unsafe_put_user(sig, &frame->sig, Efault);
+ unsafe_put_user(ksig->sig, &frame->sig, Efault);
unsafe_put_sigcontext32(&frame->sc, fp, regs, set, Efault);
unsafe_put_user(set->sig[1], &frame->extramask[0], Efault);
unsafe_put_user(ptr_to_compat(restorer), &frame->pretcode, Efault);
@@ -280,15 +275,20 @@ int ia32_setup_frame(int sig, struct ksignal *ksig,
regs->ip = (unsigned long) ksig->ka.sa.sa_handler;

/* Make -mregparm=3 work */
- regs->ax = sig;
+ regs->ax = ksig->sig;
regs->dx = 0;
regs->cx = 0;

- loadsegment(ds, __USER32_DS);
- loadsegment(es, __USER32_DS);
+#ifdef CONFIG_IA32_EMULATION
+ loadsegment(ds, __USER_DS);
+ loadsegment(es, __USER_DS);
+#else
+ regs->ds = __USER_DS;
+ regs->es = __USER_DS;
+#endif

regs->cs = __USER32_CS;
- regs->ss = __USER32_DS;
+ regs->ss = __USER_DS;

return 0;
Efault:
@@ -296,9 +296,9 @@ int ia32_setup_frame(int sig, struct ksignal *ksig,
return -EFAULT;
}

-int ia32_setup_rt_frame(int sig, struct ksignal *ksig,
- compat_sigset_t *set, struct pt_regs *regs)
+int ia32_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
{
+ sigset32_t *set = (sigset32_t *) sigmask_to_save();
struct rt_sigframe_ia32 __user *frame;
void __user *restorer;
void __user *fp = NULL;
@@ -321,7 +321,7 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig,
if (!user_access_begin(frame, sizeof(*frame)))
return -EFAULT;

- unsafe_put_user(sig, &frame->sig, Efault);
+ unsafe_put_user(ksig->sig, &frame->sig, Efault);
unsafe_put_user(ptr_to_compat(&frame->info), &frame->pinfo, Efault);
unsafe_put_user(ptr_to_compat(&frame->uc), &frame->puc, Efault);

@@ -331,7 +331,7 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig,
else
unsafe_put_user(0, &frame->uc.uc_flags, Efault);
unsafe_put_user(0, &frame->uc.uc_link, Efault);
- unsafe_compat_save_altstack(&frame->uc.uc_stack, regs->sp, Efault);
+ unsafe_save_altstack32(&frame->uc.uc_stack, regs->sp, Efault);

if (ksig->ka.sa.sa_flags & SA_RESTORER)
restorer = ksig->ka.sa.sa_restorer;
@@ -357,15 +357,20 @@ int ia32_setup_rt_frame(int sig, struct ksignal *ksig,
regs->ip = (unsigned long) ksig->ka.sa.sa_handler;

/* Make -mregparm=3 work */
- regs->ax = sig;
+ regs->ax = ksig->sig;
regs->dx = (unsigned long) &frame->info;
regs->cx = (unsigned long) &frame->uc;

- loadsegment(ds, __USER32_DS);
- loadsegment(es, __USER32_DS);
+#ifdef CONFIG_IA32_EMULATION
+ loadsegment(ds, __USER_DS);
+ loadsegment(es, __USER_DS);
+#else
+ regs->ds = __USER_DS;
+ regs->es = __USER_DS;
+#endif

regs->cs = __USER32_CS;
- regs->ss = __USER32_DS;
+ regs->ss = __USER_DS;

return 0;
Efault:
diff --git a/arch/x86/kernel/signal_64.c b/arch/x86/kernel/signal_64.c
new file mode 100644
index 000000000000..ff9c55064223
--- /dev/null
+++ b/arch/x86/kernel/signal_64.c
@@ -0,0 +1,383 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 1991, 1992 Linus Torvalds
+ * Copyright (C) 2000, 2001, 2002 Andi Kleen SuSE Labs
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/unistd.h>
+#include <linux/uaccess.h>
+#include <linux/syscalls.h>
+
+#include <asm/ucontext.h>
+#include <asm/fpu/signal.h>
+#include <asm/sighandling.h>
+
+#include <asm/syscall.h>
+#include <asm/sigframe.h>
+#include <asm/signal.h>
+
+/*
+ * If regs->ss will cause an IRET fault, change it. Otherwise leave it
+ * alone. Using this generally makes no sense unless
+ * user_64bit_mode(regs) would return true.
+ */
+static void force_valid_ss(struct pt_regs *regs)
+{
+ u32 ar;
+ asm volatile ("lar %[old_ss], %[ar]\n\t"
+ "jz 1f\n\t" /* If invalid: */
+ "xorl %[ar], %[ar]\n\t" /* set ar = 0 */
+ "1:"
+ : [ar] "=r" (ar)
+ : [old_ss] "rm" ((u16)regs->ss));
+
+ /*
+ * For a valid 64-bit user context, we need DPL 3, type
+ * read-write data or read-write exp-down data, and S and P
+ * set. We can't use VERW because VERW doesn't check the
+ * P bit.
+ */
+ ar &= AR_DPL_MASK | AR_S | AR_P | AR_TYPE_MASK;
+ if (ar != (AR_DPL3 | AR_S | AR_P | AR_TYPE_RWDATA) &&
+ ar != (AR_DPL3 | AR_S | AR_P | AR_TYPE_RWDATA_EXPDOWN))
+ regs->ss = __USER_DS;
+}
+
+static bool restore_sigcontext(struct pt_regs *regs,
+ struct sigcontext __user *usc,
+ unsigned long uc_flags)
+{
+ struct sigcontext sc;
+
+ /* Always make any pending restarted system calls return -EINTR */
+ current->restart_block.fn = do_no_restart_syscall;
+
+ if (copy_from_user(&sc, usc, offsetof(struct sigcontext, reserved1)))
+ return false;
+
+ regs->bx = sc.bx;
+ regs->cx = sc.cx;
+ regs->dx = sc.dx;
+ regs->si = sc.si;
+ regs->di = sc.di;
+ regs->bp = sc.bp;
+ regs->ax = sc.ax;
+ regs->sp = sc.sp;
+ regs->ip = sc.ip;
+ regs->r8 = sc.r8;
+ regs->r9 = sc.r9;
+ regs->r10 = sc.r10;
+ regs->r11 = sc.r11;
+ regs->r12 = sc.r12;
+ regs->r13 = sc.r13;
+ regs->r14 = sc.r14;
+ regs->r15 = sc.r15;
+
+ /* Get CS/SS and force CPL3 */
+ regs->cs = sc.cs | 0x03;
+ regs->ss = sc.ss | 0x03;
+
+ regs->flags = (regs->flags & ~FIX_EFLAGS) | (sc.flags & FIX_EFLAGS);
+ /* disable syscall checks */
+ regs->orig_ax = -1;
+
+ /*
+ * Fix up SS if needed for the benefit of old DOSEMU and
+ * CRIU.
+ */
+ if (unlikely(!(uc_flags & UC_STRICT_RESTORE_SS) && user_64bit_mode(regs)))
+ force_valid_ss(regs);
+
+ return fpu__restore_sig((void __user *)sc.fpstate, 0);
+}
+
+static __always_inline int
+__unsafe_setup_sigcontext(struct sigcontext __user *sc, void __user *fpstate,
+ struct pt_regs *regs, unsigned long mask)
+{
+ unsafe_put_user(regs->di, &sc->di, Efault);
+ unsafe_put_user(regs->si, &sc->si, Efault);
+ unsafe_put_user(regs->bp, &sc->bp, Efault);
+ unsafe_put_user(regs->sp, &sc->sp, Efault);
+ unsafe_put_user(regs->bx, &sc->bx, Efault);
+ unsafe_put_user(regs->dx, &sc->dx, Efault);
+ unsafe_put_user(regs->cx, &sc->cx, Efault);
+ unsafe_put_user(regs->ax, &sc->ax, Efault);
+ unsafe_put_user(regs->r8, &sc->r8, Efault);
+ unsafe_put_user(regs->r9, &sc->r9, Efault);
+ unsafe_put_user(regs->r10, &sc->r10, Efault);
+ unsafe_put_user(regs->r11, &sc->r11, Efault);
+ unsafe_put_user(regs->r12, &sc->r12, Efault);
+ unsafe_put_user(regs->r13, &sc->r13, Efault);
+ unsafe_put_user(regs->r14, &sc->r14, Efault);
+ unsafe_put_user(regs->r15, &sc->r15, Efault);
+
+ unsafe_put_user(current->thread.trap_nr, &sc->trapno, Efault);
+ unsafe_put_user(current->thread.error_code, &sc->err, Efault);
+ unsafe_put_user(regs->ip, &sc->ip, Efault);
+ unsafe_put_user(regs->flags, &sc->flags, Efault);
+ unsafe_put_user(regs->cs, &sc->cs, Efault);
+ unsafe_put_user(0, &sc->gs, Efault);
+ unsafe_put_user(0, &sc->fs, Efault);
+ unsafe_put_user(regs->ss, &sc->ss, Efault);
+
+ unsafe_put_user(fpstate, (unsigned long __user *)&sc->fpstate, Efault);
+
+ /* non-iBCS2 extensions.. */
+ unsafe_put_user(mask, &sc->oldmask, Efault);
+ unsafe_put_user(current->thread.cr2, &sc->cr2, Efault);
+ return 0;
+Efault:
+ return -EFAULT;
+}
+
+#define unsafe_put_sigcontext(sc, fp, regs, set, label) \
+do { \
+ if (__unsafe_setup_sigcontext(sc, fp, regs, set->sig[0])) \
+ goto label; \
+} while(0);
+
+#define unsafe_put_sigmask(set, frame, label) \
+ unsafe_put_user(*(__u64 *)(set), \
+ (__u64 __user *)&(frame)->uc.uc_sigmask, \
+ label)
+
+static unsigned long frame_uc_flags(struct pt_regs *regs)
+{
+ unsigned long flags;
+
+ if (boot_cpu_has(X86_FEATURE_XSAVE))
+ flags = UC_FP_XSTATE | UC_SIGCONTEXT_SS;
+ else
+ flags = UC_SIGCONTEXT_SS;
+
+ if (likely(user_64bit_mode(regs)))
+ flags |= UC_STRICT_RESTORE_SS;
+
+ return flags;
+}
+
+int x64_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
+{
+ sigset_t *set = sigmask_to_save();
+ struct rt_sigframe __user *frame;
+ void __user *fp = NULL;
+ unsigned long uc_flags;
+
+ /* x86-64 should always use SA_RESTORER. */
+ if (!(ksig->ka.sa.sa_flags & SA_RESTORER))
+ return -EFAULT;
+
+ frame = get_sigframe(ksig, regs, sizeof(struct rt_sigframe), &fp);
+ uc_flags = frame_uc_flags(regs);
+
+ if (!user_access_begin(frame, sizeof(*frame)))
+ return -EFAULT;
+
+ /* Create the ucontext. */
+ unsafe_put_user(uc_flags, &frame->uc.uc_flags, Efault);
+ unsafe_put_user(0, &frame->uc.uc_link, Efault);
+ unsafe_save_altstack(&frame->uc.uc_stack, regs->sp, Efault);
+
+ /* Set up to return from userspace. If provided, use a stub
+ already in userspace. */
+ unsafe_put_user(ksig->ka.sa.sa_restorer, &frame->pretcode, Efault);
+ unsafe_put_sigcontext(&frame->uc.uc_mcontext, fp, regs, set, Efault);
+ unsafe_put_sigmask(set, frame, Efault);
+ user_access_end();
+
+ if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
+ if (copy_siginfo_to_user(&frame->info, &ksig->info))
+ return -EFAULT;
+ }
+
+ /* Set up registers for signal handler */
+ regs->di = ksig->sig;
+ /* In case the signal handler was declared without prototypes */
+ regs->ax = 0;
+
+ /* This also works for non SA_SIGINFO handlers because they expect the
+ next argument after the signal number on the stack. */
+ regs->si = (unsigned long)&frame->info;
+ regs->dx = (unsigned long)&frame->uc;
+ regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
+
+ regs->sp = (unsigned long)frame;
+
+ /*
+ * Set up the CS and SS registers to run signal handlers in
+ * 64-bit mode, even if the handler happens to be interrupting
+ * 32-bit or 16-bit code.
+ *
+ * SS is subtle. In 64-bit mode, we don't need any particular
+ * SS descriptor, but we do need SS to be valid. It's possible
+ * that the old SS is entirely bogus -- this can happen if the
+ * signal we're trying to deliver is #GP or #SS caused by a bad
+ * SS value. We also have a compatibility issue here: DOSEMU
+ * relies on the contents of the SS register indicating the
+ * SS value at the time of the signal, even though that code in
+ * DOSEMU predates sigreturn's ability to restore SS. (DOSEMU
+ * avoids relying on sigreturn to restore SS; instead it uses
+ * a trampoline.) So we do our best: if the old SS was valid,
+ * we keep it. Otherwise we replace it.
+ */
+ regs->cs = __USER_CS;
+
+ if (unlikely(regs->ss != __USER_DS))
+ force_valid_ss(regs);
+
+ return 0;
+
+Efault:
+ user_access_end();
+ return -EFAULT;
+}
+
+/*
+ * Do a signal return; undo the signal stack.
+ */
+SYSCALL_DEFINE0(rt_sigreturn)
+{
+ struct pt_regs *regs = current_pt_regs();
+ struct rt_sigframe __user *frame;
+ sigset_t set;
+ unsigned long uc_flags;
+
+ frame = (struct rt_sigframe __user *)(regs->sp - sizeof(long));
+ if (!access_ok(frame, sizeof(*frame)))
+ goto badframe;
+ if (__get_user(*(__u64 *)&set, (__u64 __user *)&frame->uc.uc_sigmask))
+ goto badframe;
+ if (__get_user(uc_flags, &frame->uc.uc_flags))
+ goto badframe;
+
+ set_current_blocked(&set);
+
+ if (!restore_sigcontext(regs, &frame->uc.uc_mcontext, uc_flags))
+ goto badframe;
+
+ if (restore_altstack(&frame->uc.uc_stack))
+ goto badframe;
+
+ return regs->ax;
+
+badframe:
+ signal_fault(regs, frame, "rt_sigreturn");
+ return 0;
+}
+
+#ifdef CONFIG_X86_X32_ABI
+static int x32_copy_siginfo_to_user(struct compat_siginfo __user *to,
+ const struct kernel_siginfo *from)
+{
+ struct compat_siginfo new;
+
+ copy_siginfo_to_external32(&new, from);
+ if (from->si_signo == SIGCHLD) {
+ new._sifields._sigchld_x32._utime = from->si_utime;
+ new._sifields._sigchld_x32._stime = from->si_stime;
+ }
+ if (copy_to_user(to, &new, sizeof(struct compat_siginfo)))
+ return -EFAULT;
+ return 0;
+}
+
+int copy_siginfo_to_user32(struct compat_siginfo __user *to,
+ const struct kernel_siginfo *from)
+{
+ if (in_x32_syscall())
+ return x32_copy_siginfo_to_user(to, from);
+ return __copy_siginfo_to_user32(to, from);
+}
+
+int x32_setup_rt_frame(struct ksignal *ksig, struct pt_regs *regs)
+{
+ compat_sigset_t *set = (compat_sigset_t *) sigmask_to_save();
+ struct rt_sigframe_x32 __user *frame;
+ unsigned long uc_flags;
+ void __user *restorer;
+ void __user *fp = NULL;
+
+ if (!(ksig->ka.sa.sa_flags & SA_RESTORER))
+ return -EFAULT;
+
+ frame = get_sigframe(ksig, regs, sizeof(*frame), &fp);
+
+ uc_flags = frame_uc_flags(regs);
+
+ if (!user_access_begin(frame, sizeof(*frame)))
+ return -EFAULT;
+
+ /* Create the ucontext. */
+ unsafe_put_user(uc_flags, &frame->uc.uc_flags, Efault);
+ unsafe_put_user(0, &frame->uc.uc_link, Efault);
+ unsafe_compat_save_altstack(&frame->uc.uc_stack, regs->sp, Efault);
+ unsafe_put_user(0, &frame->uc.uc__pad0, Efault);
+ restorer = ksig->ka.sa.sa_restorer;
+ unsafe_put_user(restorer, (unsigned long __user *)&frame->pretcode, Efault);
+ unsafe_put_sigcontext(&frame->uc.uc_mcontext, fp, regs, set, Efault);
+ unsafe_put_sigmask(set, frame, Efault);
+ user_access_end();
+
+ if (ksig->ka.sa.sa_flags & SA_SIGINFO) {
+ if (x32_copy_siginfo_to_user(&frame->info, &ksig->info))
+ return -EFAULT;
+ }
+
+ /* Set up registers for signal handler */
+ regs->sp = (unsigned long) frame;
+ regs->ip = (unsigned long) ksig->ka.sa.sa_handler;
+
+ /* We use the x32 calling convention here... */
+ regs->di = ksig->sig;
+ regs->si = (unsigned long) &frame->info;
+ regs->dx = (unsigned long) &frame->uc;
+
+ loadsegment(ds, __USER_DS);
+ loadsegment(es, __USER_DS);
+
+ regs->cs = __USER_CS;
+ regs->ss = __USER_DS;
+
+ return 0;
+
+Efault:
+ user_access_end();
+ return -EFAULT;
+}
+
+COMPAT_SYSCALL_DEFINE0(x32_rt_sigreturn)
+{
+ struct pt_regs *regs = current_pt_regs();
+ struct rt_sigframe_x32 __user *frame;
+ sigset_t set;
+ unsigned long uc_flags;
+
+ frame = (struct rt_sigframe_x32 __user *)(regs->sp - 8);
+
+ if (!access_ok(frame, sizeof(*frame)))
+ goto badframe;
+ if (__get_user(set.sig[0], (__u64 __user *)&frame->uc.uc_sigmask))
+ goto badframe;
+ if (__get_user(uc_flags, &frame->uc.uc_flags))
+ goto badframe;
+
+ set_current_blocked(&set);
+
+ if (!restore_sigcontext(regs, &frame->uc.uc_mcontext, uc_flags))
+ goto badframe;
+
+ if (compat_restore_altstack(&frame->uc.uc_stack))
+ goto badframe;
+
+ return regs->ax;
+
+badframe:
+ signal_fault(regs, frame, "x32 rt_sigreturn");
+ return 0;
+}
+#endif /* CONFIG_X86_X32_ABI */
diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S
index 6b4fdf6b9542..4a184f6e4e4d 100644
--- a/arch/x86/xen/xen-asm.S
+++ b/arch/x86/xen/xen-asm.S
@@ -262,10 +262,10 @@ SYM_CODE_START(xen_entry_SYSCALL_compat)

/*
* Neither Xen nor the kernel really knows what the old SS and
- * CS were. The kernel expects __USER32_DS and __USER32_CS, so
+ * CS were. The kernel expects __USER_DS and __USER32_CS, so
* report those values even though Xen will guess its own values.
*/
- movq $__USER32_DS, 4*8(%rsp)
+ movq $__USER_DS, 4*8(%rsp)
movq $__USER32_CS, 1*8(%rsp)

jmp entry_SYSCALL_compat_after_hwframe
@@ -284,10 +284,10 @@ SYM_CODE_START(xen_entry_SYSENTER_compat)

/*
* Neither Xen nor the kernel really knows what the old SS and
- * CS were. The kernel expects __USER32_DS and __USER32_CS, so
+ * CS were. The kernel expects __USER_DS and __USER32_CS, so
* report those values even though Xen will guess its own values.
*/
- movq $__USER32_DS, 4*8(%rsp)
+ movq $__USER_DS, 4*8(%rsp)
movq $__USER32_CS, 1*8(%rsp)

jmp entry_SYSENTER_compat_after_hwframe
diff --git a/include/linux/compat.h b/include/linux/compat.h
index 594357881b0b..44b1736c95b5 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -126,11 +126,9 @@ struct compat_tms {

#define _COMPAT_NSIG_WORDS (_COMPAT_NSIG / _COMPAT_NSIG_BPW)

-#ifndef compat_sigset_t
typedef struct {
compat_sigset_word sig[_COMPAT_NSIG_WORDS];
} compat_sigset_t;
-#endif

int set_compat_user_sigmask(const compat_sigset_t __user *umask,
size_t sigsetsize);
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h
index a34b0f9a9972..33a0ee3bcb2e 100644
--- a/include/linux/syscalls.h
+++ b/include/linux/syscalls.h
@@ -264,6 +264,7 @@ static inline int is_syscall_trace_event(struct trace_event_call *tp_event)
#define SC_VAL64(type, name) ((type) name##_hi << 32 | name##_lo)

#ifdef CONFIG_COMPAT
+#define SYSCALL32_DEFINE0 COMPAT_SYSCALL_DEFINE0
#define SYSCALL32_DEFINE1 COMPAT_SYSCALL_DEFINE1
#define SYSCALL32_DEFINE2 COMPAT_SYSCALL_DEFINE2
#define SYSCALL32_DEFINE3 COMPAT_SYSCALL_DEFINE3
@@ -271,6 +272,7 @@ static inline int is_syscall_trace_event(struct trace_event_call *tp_event)
#define SYSCALL32_DEFINE5 COMPAT_SYSCALL_DEFINE5
#define SYSCALL32_DEFINE6 COMPAT_SYSCALL_DEFINE6
#else
+#define SYSCALL32_DEFINE0 SYSCALL_DEFINE0
#define SYSCALL32_DEFINE1 SYSCALL_DEFINE1
#define SYSCALL32_DEFINE2 SYSCALL_DEFINE2
#define SYSCALL32_DEFINE3 SYSCALL_DEFINE3