[PATCH] s390: put sys_call_table into .rodata section and write protect it (d882b172) · Commits · 戴 / test

arch/s390/kernel/entry.S

+6 −3

Original line number	Diff line number	Diff line
		@@ -228,8 +228,9 @@ sysc_do_svc:
		sysc_nr_ok:
		mvc SP_ARGS(4,%r15),SP_R7(%r15)
		sysc_do_restart:
		l %r8,BASED(.Lsysc_table)
		tm __TI_flags+3(%r9),(_TIF_SYSCALL_TRACE\|_TIF_SYSCALL_AUDIT)
		l %r8,sys_call_table-system_call(%r7,%r13) # get system call addr.
		l %r8,0(%r7,%r8) # get system call addr.
		bnz BASED(sysc_tracesys)
		basr %r14,%r8 # call sys_xxxx
		st %r2,SP_R2(%r15) # store return value (change R2 on stack)
		@@ -330,9 +331,10 @@ sysc_tracesys:
		basr %r14,%r1
		clc SP_R2(4,%r15),BASED(.Lnr_syscalls)
		bnl BASED(sysc_tracenogo)
		l %r8,BASED(.Lsysc_table)
		l %r7,SP_R2(%r15) # strace might have changed the
		sll %r7,2 # system call
		l %r8,sys_call_table-system_call(%r7,%r13)
		l %r8,0(%r7,%r8)
		sysc_tracego:
		lm %r3,%r6,SP_R3(%r15)
		l %r2,SP_ORIG_R2(%r15)
		@@ -1009,6 +1011,7 @@ cleanup_io_leave_insn:
		.Ltrace: .long syscall_trace
		.Lvfork: .long sys_vfork
		.Lschedtail: .long schedule_tail
		.Lsysc_table: .long sys_call_table

		.Lcritical_start:
		.long __critical_start + 0x80000000
		@@ -1017,8 +1020,8 @@ cleanup_io_leave_insn:
		.Lcleanup_critical:
		.long cleanup_critical

		.section .rodata, "a"
		#define SYSCALL(esa,esame,emu) .long esa
		sys_call_table:
		#include "syscalls.S"
		#undef SYSCALL

arch/s390/kernel/entry64.S

+1 −0

Original line number	Diff line number	Diff line
		@@ -991,6 +991,7 @@ cleanup_io_leave_insn:
		.Lcritical_end:
		.quad __critical_end

		.section .rodata, "a"
		#define SYSCALL(esa,esame,emu) .long esame
		sys_call_table:
		#include "syscalls.S"

arch/s390/mm/init.c

+21 −14

Original line number	Diff line number	Diff line
		@@ -23,6 +23,7 @@
		#include <linux/init.h>
		#include <linux/pagemap.h>
		#include <linux/bootmem.h>
		#include <linux/pfn.h>

		#include <asm/processor.h>
		#include <asm/system.h>
		@@ -33,6 +34,7 @@
		#include <asm/lowcore.h>
		#include <asm/tlb.h>
		#include <asm/tlbflush.h>
		#include <asm/sections.h>

		DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);

		@@ -89,17 +91,6 @@ void show_mem(void)
		printk("%d pages swap cached\n",cached);
		}

		/* References to section boundaries */

		extern unsigned long _text;
		extern unsigned long _etext;
		extern unsigned long _edata;
		extern unsigned long __bss_start;
		extern unsigned long _end;

		extern unsigned long __init_begin;
		extern unsigned long __init_end;

		extern unsigned long __initdata zholes_size[];
		/*
		* paging_init() sets up the page tables
		@@ -116,6 +107,10 @@ void __init paging_init(void)
		unsigned long pfn = 0;
		unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) \| _KERNSEG_TABLE;
		static const int ssm_mask = 0x04000000L;
		unsigned long ro_start_pfn, ro_end_pfn;

		ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata);
		ro_end_pfn = PFN_UP((unsigned long)&__end_rodata);

		/* unmap whole virtual address space */

		@@ -143,6 +138,9 @@ void __init paging_init(void)
		pg_dir++;

		for (tmp = 0 ; tmp < PTRS_PER_PTE ; tmp++,pg_table++) {
		if (pfn >= ro_start_pfn && pfn < ro_end_pfn)
		pte = pfn_pte(pfn, __pgprot(_PAGE_RO));
		else
		pte = pfn_pte(pfn, PAGE_KERNEL);
		if (pfn >= max_low_pfn)
		pte_clear(&init_mm, 0, &pte);
		@@ -175,6 +173,7 @@ void __init paging_init(void)
		}

		#else /* CONFIG_64BIT */

		void __init paging_init(void)
		{
		pgd_t * pg_dir;
		@@ -186,13 +185,15 @@ void __init paging_init(void)
		unsigned long pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) \|
		_KERN_REGION_TABLE;
		static const int ssm_mask = 0x04000000L;

		unsigned long zones_size[MAX_NR_ZONES];
		unsigned long dma_pfn, high_pfn;
		unsigned long ro_start_pfn, ro_end_pfn;

		memset(zones_size, 0, sizeof(zones_size));
		dma_pfn = MAX_DMA_ADDRESS >> PAGE_SHIFT;
		high_pfn = max_low_pfn;
		ro_start_pfn = PFN_DOWN((unsigned long)&__start_rodata);
		ro_end_pfn = PFN_UP((unsigned long)&__end_rodata);

		if (dma_pfn > high_pfn)
		zones_size[ZONE_DMA] = high_pfn;
		@@ -231,6 +232,9 @@ void __init paging_init(void)
		pmd_populate_kernel(&init_mm, pm_dir, pt_dir);

		for (k = 0 ; k < PTRS_PER_PTE ; k++,pt_dir++) {
		if (pfn >= ro_start_pfn && pfn < ro_end_pfn)
		pte = pfn_pte(pfn, __pgprot(_PAGE_RO));
		else
		pte = pfn_pte(pfn, PAGE_KERNEL);
		if (pfn >= max_low_pfn) {
		pte_clear(&init_mm, 0, &pte);
		@@ -282,6 +286,9 @@ void __init mem_init(void)
		reservedpages << (PAGE_SHIFT-10),
		datasize >>10,
		initsize >> 10);
		printk("Write protected kernel read-only data: %#lx - %#lx\n",
		(unsigned long)&__start_rodata,
		PFN_ALIGN((unsigned long)&__end_rodata) - 1);
		}

		void free_initmem(void)

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