Commit e35ac62d authored by Russell King's avatar Russell King

Merge branch 'security-fixes' into fixes

parents 24195cad 8c0cc8a5
......@@ -130,8 +130,10 @@ struct mm_struct;
extern unsigned long arch_randomize_brk(struct mm_struct *mm);
#define arch_randomize_brk arch_randomize_brk
#ifdef CONFIG_MMU
#define ARCH_HAS_SETUP_ADDITIONAL_PAGES 1
struct linux_binprm;
int arch_setup_additional_pages(struct linux_binprm *, int);
#endif
#endif
......@@ -474,17 +474,18 @@ const char *arch_vma_name(struct vm_area_struct *vma)
"[sigpage]" : NULL;
}
static struct page *signal_page;
extern struct page *get_signal_page(void);
int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
{
struct mm_struct *mm = current->mm;
struct page *page;
unsigned long addr;
int ret;
page = get_signal_page();
if (!page)
if (!signal_page)
signal_page = get_signal_page();
if (!signal_page)
return -ENOMEM;
down_write(&mm->mmap_sem);
......@@ -496,7 +497,7 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
ret = install_special_mapping(mm, addr, PAGE_SIZE,
VM_READ | VM_EXEC | VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC,
&page);
&signal_page);
if (ret == 0)
mm->context.sigpage = addr;
......
......@@ -402,7 +402,8 @@ setup_return(struct pt_regs *regs, struct ksignal *ksig,
__put_user(sigreturn_codes[idx+1], rc+1))
return 1;
if ((cpsr & MODE32_BIT) && !IS_ENABLED(CONFIG_ARM_MPU)) {
#ifdef CONFIG_MMU
if (cpsr & MODE32_BIT) {
struct mm_struct *mm = current->mm;
/*
......@@ -412,7 +413,9 @@ setup_return(struct pt_regs *regs, struct ksignal *ksig,
*/
retcode = mm->context.sigpage + signal_return_offset +
(idx << 2) + thumb;
} else {
} else
#endif
{
/*
* Ensure that the instruction cache sees
* the return code written onto the stack.
......@@ -614,21 +617,19 @@ do_work_pending(struct pt_regs *regs, unsigned int thread_flags, int syscall)
return 0;
}
static struct page *signal_page;
struct page *get_signal_page(void)
{
if (!signal_page) {
unsigned long ptr;
unsigned offset;
struct page *page;
void *addr;
signal_page = alloc_pages(GFP_KERNEL, 0);
page = alloc_pages(GFP_KERNEL, 0);
if (!signal_page)
if (!page)
return NULL;
addr = page_address(signal_page);
addr = page_address(page);
/* Give the signal return code some randomness */
offset = 0x200 + (get_random_int() & 0x7fc);
......@@ -642,7 +643,6 @@ struct page *get_signal_page(void)
ptr = (unsigned long)addr + offset;
flush_icache_range(ptr, ptr + sizeof(sigreturn_codes));
}
return signal_page;
return page;
}
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