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-rw-r--r--arch/sh/kernel/vsyscall/.gitignore2
-rw-r--r--arch/sh/kernel/vsyscall/Makefile36
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall-note.S26
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall-sigreturn.S75
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall-syscall.S11
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall-trapa.S40
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall.c93
-rw-r--r--arch/sh/kernel/vsyscall/vsyscall.lds.S85
8 files changed, 368 insertions, 0 deletions
diff --git a/arch/sh/kernel/vsyscall/.gitignore b/arch/sh/kernel/vsyscall/.gitignore
new file mode 100644
index 000000000..530a3031a
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/.gitignore
@@ -0,0 +1,2 @@
+# SPDX-License-Identifier: GPL-2.0-only
+vsyscall.lds
diff --git a/arch/sh/kernel/vsyscall/Makefile b/arch/sh/kernel/vsyscall/Makefile
new file mode 100644
index 000000000..6e8664448
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/Makefile
@@ -0,0 +1,36 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-y += vsyscall.o vsyscall-syscall.o vsyscall-syms.o
+
+$(obj)/vsyscall-syscall.o: \
+ $(foreach F,trapa,$(obj)/vsyscall-$F.so)
+
+# Teach kbuild about targets
+targets += $(foreach F,trapa,vsyscall-$F.o vsyscall-$F.so)
+targets += vsyscall-note.o vsyscall.lds vsyscall-dummy.o
+
+# The DSO images are built using a special linker script
+quiet_cmd_syscall = SYSCALL $@
+ cmd_syscall = $(CC) -nostdlib $(SYSCFLAGS_$(@F)) \
+ -Wl,-T,$(filter-out FORCE,$^) -o $@
+
+export CPPFLAGS_vsyscall.lds += -P -C -Ush
+
+vsyscall-flags = -shared -s -Wl,-soname=linux-gate.so.1 -Wl,--hash-style=sysv
+
+SYSCFLAGS_vsyscall-trapa.so = $(vsyscall-flags)
+
+$(obj)/vsyscall-trapa.so: \
+$(obj)/vsyscall-%.so: $(src)/vsyscall.lds $(obj)/vsyscall-%.o FORCE
+ $(call if_changed,syscall)
+
+# We also create a special relocatable object that should mirror the symbol
+# table and layout of the linked DSO. With ld -R we can then refer to
+# these symbols in the kernel code rather than hand-coded addresses.
+SYSCFLAGS_vsyscall-dummy.o = -r
+$(obj)/vsyscall-dummy.o: $(src)/vsyscall.lds \
+ $(obj)/vsyscall-trapa.o $(obj)/vsyscall-note.o FORCE
+ $(call if_changed,syscall)
+
+LDFLAGS_vsyscall-syms.o := -r -R
+$(obj)/vsyscall-syms.o: $(obj)/vsyscall-dummy.o FORCE
+ $(call if_changed,ld)
diff --git a/arch/sh/kernel/vsyscall/vsyscall-note.S b/arch/sh/kernel/vsyscall/vsyscall-note.S
new file mode 100644
index 000000000..bb350918b
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall-note.S
@@ -0,0 +1,26 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * This supplies .note.* sections to go into the PT_NOTE inside the vDSO text.
+ * Here we can supply some information useful to userland.
+ */
+
+#include <linux/uts.h>
+#include <linux/version.h>
+
+#define ASM_ELF_NOTE_BEGIN(name, flags, vendor, type) \
+ .section name, flags; \
+ .balign 4; \
+ .long 1f - 0f; /* name length */ \
+ .long 3f - 2f; /* data length */ \
+ .long type; /* note type */ \
+0: .asciz vendor; /* vendor name */ \
+1: .balign 4; \
+2:
+
+#define ASM_ELF_NOTE_END \
+3: .balign 4; /* pad out section */ \
+ .previous
+
+ ASM_ELF_NOTE_BEGIN(".note.kernel-version", "a", UTS_SYSNAME, 0)
+ .long LINUX_VERSION_CODE
+ ASM_ELF_NOTE_END
diff --git a/arch/sh/kernel/vsyscall/vsyscall-sigreturn.S b/arch/sh/kernel/vsyscall/vsyscall-sigreturn.S
new file mode 100644
index 000000000..bece5fa73
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall-sigreturn.S
@@ -0,0 +1,75 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <asm/unistd.h>
+
+ .text
+ .balign 32
+ .globl __kernel_sigreturn
+ .type __kernel_sigreturn,@function
+__kernel_sigreturn:
+.LSTART_sigreturn:
+ mov.w 1f, r3
+ trapa #0x10
+ or r0, r0
+ or r0, r0
+ or r0, r0
+ or r0, r0
+ or r0, r0
+
+1: .short __NR_sigreturn
+.LEND_sigreturn:
+ .size __kernel_sigreturn,.-.LSTART_sigreturn
+
+ .balign 32
+ .globl __kernel_rt_sigreturn
+ .type __kernel_rt_sigreturn,@function
+__kernel_rt_sigreturn:
+.LSTART_rt_sigreturn:
+ mov.w 1f, r3
+ trapa #0x10
+ or r0, r0
+ or r0, r0
+ or r0, r0
+ or r0, r0
+ or r0, r0
+
+1: .short __NR_rt_sigreturn
+.LEND_rt_sigreturn:
+ .size __kernel_rt_sigreturn,.-.LSTART_rt_sigreturn
+ .previous
+
+ .section .eh_frame,"a",@progbits
+.LCIE1:
+ .ualong .LCIE1_end - .LCIE1_start
+.LCIE1_start:
+ .ualong 0 /* CIE ID */
+ .byte 0x1 /* Version number */
+ .string "zRS" /* NUL-terminated augmentation string */
+ .uleb128 0x1 /* Code alignment factor */
+ .sleb128 -4 /* Data alignment factor */
+ .byte 0x11 /* Return address register column */
+ .uleb128 0x1 /* Augmentation length and data */
+ .byte 0x1b /* DW_EH_PE_pcrel | DW_EH_PE_sdata4. */
+ .byte 0xc, 0xf, 0x0 /* DW_CFA_def_cfa: r15 ofs 0 */
+
+ .align 2
+.LCIE1_end:
+
+ .ualong .LFDE0_end-.LFDE0_start /* Length FDE0 */
+.LFDE0_start:
+ .ualong .LFDE0_start-.LCIE1 /* CIE pointer */
+ .ualong .LSTART_sigreturn-. /* PC-relative start address */
+ .ualong .LEND_sigreturn-.LSTART_sigreturn
+ .uleb128 0 /* Augmentation */
+ .align 2
+.LFDE0_end:
+
+ .ualong .LFDE1_end-.LFDE1_start /* Length FDE1 */
+.LFDE1_start:
+ .ualong .LFDE1_start-.LCIE1 /* CIE pointer */
+ .ualong .LSTART_rt_sigreturn-. /* PC-relative start address */
+ .ualong .LEND_rt_sigreturn-.LSTART_rt_sigreturn
+ .uleb128 0 /* Augmentation */
+ .align 2
+.LFDE1_end:
+
+ .previous
diff --git a/arch/sh/kernel/vsyscall/vsyscall-syscall.S b/arch/sh/kernel/vsyscall/vsyscall-syscall.S
new file mode 100644
index 000000000..2aeaa2dde
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall-syscall.S
@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/init.h>
+
+__INITDATA
+
+ .globl vsyscall_trapa_start, vsyscall_trapa_end
+vsyscall_trapa_start:
+ .incbin "arch/sh/kernel/vsyscall/vsyscall-trapa.so"
+vsyscall_trapa_end:
+
+__FINIT
diff --git a/arch/sh/kernel/vsyscall/vsyscall-trapa.S b/arch/sh/kernel/vsyscall/vsyscall-trapa.S
new file mode 100644
index 000000000..854ea3235
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall-trapa.S
@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+ .text
+ .globl __kernel_vsyscall
+ .type __kernel_vsyscall,@function
+__kernel_vsyscall:
+.LSTART_vsyscall:
+ trapa #0x10
+ nop
+.LEND_vsyscall:
+ .size __kernel_vsyscall,.-.LSTART_vsyscall
+ .previous
+
+ .section .eh_frame,"a",@progbits
+.LCIE:
+ .ualong .LCIE_end - .LCIE_start
+.LCIE_start:
+ .ualong 0 /* CIE ID */
+ .byte 0x1 /* Version number */
+ .string "zR" /* NUL-terminated augmentation string */
+ .uleb128 0x1 /* Code alignment factor */
+ .sleb128 -4 /* Data alignment factor */
+ .byte 0x11 /* Return address register column */
+ .uleb128 0x1 /* Augmentation length and data */
+ .byte 0x1b /* DW_EH_PE_pcrel | DW_EH_PE_sdata4. */
+ .byte 0xc,0xf,0x0 /* DW_CFA_def_cfa: r15 ofs 0 */
+ .align 2
+.LCIE_end:
+
+ .ualong .LFDE_end-.LFDE_start /* Length FDE */
+.LFDE_start:
+ .ualong .LFDE_start-.LCIE /* CIE pointer */
+ .ualong .LSTART_vsyscall-. /* PC-relative start address */
+ .ualong .LEND_vsyscall-.LSTART_vsyscall
+ .uleb128 0 /* Augmentation */
+ .align 2
+.LFDE_end:
+ .previous
+
+/* Get the common code for the sigreturn entry points */
+#include "vsyscall-sigreturn.S"
diff --git a/arch/sh/kernel/vsyscall/vsyscall.c b/arch/sh/kernel/vsyscall/vsyscall.c
new file mode 100644
index 000000000..1bd85a694
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall.c
@@ -0,0 +1,93 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * arch/sh/kernel/vsyscall/vsyscall.c
+ *
+ * Copyright (C) 2006 Paul Mundt
+ *
+ * vDSO randomization
+ * Copyright(C) 2005-2006, Red Hat, Inc., Ingo Molnar
+ */
+#include <linux/mm.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/gfp.h>
+#include <linux/module.h>
+#include <linux/elf.h>
+#include <linux/sched.h>
+#include <linux/err.h>
+
+/*
+ * Should the kernel map a VDSO page into processes and pass its
+ * address down to glibc upon exec()?
+ */
+unsigned int __read_mostly vdso_enabled = 1;
+EXPORT_SYMBOL_GPL(vdso_enabled);
+
+static int __init vdso_setup(char *s)
+{
+ vdso_enabled = simple_strtoul(s, NULL, 0);
+ return 1;
+}
+__setup("vdso=", vdso_setup);
+
+/*
+ * These symbols are defined by vsyscall.o to mark the bounds
+ * of the ELF DSO images included therein.
+ */
+extern const char vsyscall_trapa_start, vsyscall_trapa_end;
+static struct page *syscall_pages[1];
+
+int __init vsyscall_init(void)
+{
+ void *syscall_page = (void *)get_zeroed_page(GFP_ATOMIC);
+ syscall_pages[0] = virt_to_page(syscall_page);
+
+ /*
+ * XXX: Map this page to a fixmap entry if we get around
+ * to adding the page to ELF core dumps
+ */
+
+ memcpy(syscall_page,
+ &vsyscall_trapa_start,
+ &vsyscall_trapa_end - &vsyscall_trapa_start);
+
+ return 0;
+}
+
+/* Setup a VMA at program startup for the vsyscall page */
+int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
+{
+ struct mm_struct *mm = current->mm;
+ unsigned long addr;
+ int ret;
+
+ if (mmap_write_lock_killable(mm))
+ return -EINTR;
+
+ addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0);
+ if (IS_ERR_VALUE(addr)) {
+ ret = addr;
+ goto up_fail;
+ }
+
+ ret = install_special_mapping(mm, addr, PAGE_SIZE,
+ VM_READ | VM_EXEC |
+ VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
+ syscall_pages);
+ if (unlikely(ret))
+ goto up_fail;
+
+ current->mm->context.vdso = (void *)addr;
+
+up_fail:
+ mmap_write_unlock(mm);
+ return ret;
+}
+
+const char *arch_vma_name(struct vm_area_struct *vma)
+{
+ if (vma->vm_mm && vma->vm_start == (long)vma->vm_mm->context.vdso)
+ return "[vdso]";
+
+ return NULL;
+}
diff --git a/arch/sh/kernel/vsyscall/vsyscall.lds.S b/arch/sh/kernel/vsyscall/vsyscall.lds.S
new file mode 100644
index 000000000..e3582e03c
--- /dev/null
+++ b/arch/sh/kernel/vsyscall/vsyscall.lds.S
@@ -0,0 +1,85 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Linker script for vsyscall DSO. The vsyscall page is an ELF shared
+ * object prelinked to its virtual address, and with only one read-only
+ * segment (that fits in one page). This script controls its layout.
+ */
+#include <asm/asm-offsets.h>
+
+#ifdef CONFIG_CPU_LITTLE_ENDIAN
+OUTPUT_FORMAT("elf32-sh-linux", "elf32-sh-linux", "elf32-sh-linux")
+#else
+OUTPUT_FORMAT("elf32-shbig-linux", "elf32-shbig-linux", "elf32-shbig-linux")
+#endif
+OUTPUT_ARCH(sh)
+
+/* The ELF entry point can be used to set the AT_SYSINFO value. */
+ENTRY(__kernel_vsyscall);
+
+SECTIONS
+{
+ . = SIZEOF_HEADERS;
+
+ .hash : { *(.hash) } :text
+ .gnu.hash : { *(.gnu.hash) }
+ .dynsym : { *(.dynsym) }
+ .dynstr : { *(.dynstr) }
+ .gnu.version : { *(.gnu.version) }
+ .gnu.version_d : { *(.gnu.version_d) }
+ .gnu.version_r : { *(.gnu.version_r) }
+
+ /*
+ * This linker script is used both with -r and with -shared.
+ * For the layouts to match, we need to skip more than enough
+ * space for the dynamic symbol table et al. If this amount
+ * is insufficient, ld -shared will barf. Just increase it here.
+ */
+ . = 0x400;
+
+ .text : { *(.text) } :text =0x90909090
+ .note : { *(.note.*) } :text :note
+ .eh_frame_hdr : { *(.eh_frame_hdr ) } :text :eh_frame_hdr
+ .eh_frame : {
+ KEEP (*(.eh_frame))
+ LONG (0)
+ } :text
+ .dynamic : { *(.dynamic) } :text :dynamic
+ .useless : {
+ *(.got.plt) *(.got)
+ *(.data .data.* .gnu.linkonce.d.*)
+ *(.dynbss)
+ *(.bss .bss.* .gnu.linkonce.b.*)
+ } :text
+}
+
+/*
+ * Very old versions of ld do not recognize this name token; use the constant.
+ */
+#define PT_GNU_EH_FRAME 0x6474e550
+
+/*
+ * We must supply the ELF program headers explicitly to get just one
+ * PT_LOAD segment, and set the flags explicitly to make segments read-only.
+ */
+PHDRS
+{
+ text PT_LOAD FILEHDR PHDRS FLAGS(5); /* PF_R|PF_X */
+ dynamic PT_DYNAMIC FLAGS(4); /* PF_R */
+ note PT_NOTE FLAGS(4); /* PF_R */
+ eh_frame_hdr PT_GNU_EH_FRAME;
+}
+
+/*
+ * This controls what symbols we export from the DSO.
+ */
+VERSION
+{
+ LINUX_2.6 {
+ global:
+ __kernel_vsyscall;
+ __kernel_sigreturn;
+ __kernel_rt_sigreturn;
+
+ local: *;
+ };
+}