diff options
Diffstat (limited to 'arch/x86/lib/usercopy_32.c')
| -rw-r--r-- | arch/x86/lib/usercopy_32.c | 84 |
1 files changed, 15 insertions, 69 deletions
diff --git a/arch/x86/lib/usercopy_32.c b/arch/x86/lib/usercopy_32.c index 1781b2f950e..e2f5e21c03b 100644 --- a/arch/x86/lib/usercopy_32.c +++ b/arch/x86/lib/usercopy_32.c @@ -42,10 +42,11 @@ do { \ int __d0; \ might_fault(); \ __asm__ __volatile__( \ + ASM_STAC "\n" \ "0: rep; stosl\n" \ " movl %2,%0\n" \ "1: rep; stosb\n" \ - "2:\n" \ + "2: " ASM_CLAC "\n" \ ".section .fixup,\"ax\"\n" \ "3: lea 0(%2,%0,4),%0\n" \ " jmp 2b\n" \ @@ -569,67 +570,12 @@ do { \ unsigned long __copy_to_user_ll(void __user *to, const void *from, unsigned long n) { -#ifndef CONFIG_X86_WP_WORKS_OK - if (unlikely(boot_cpu_data.wp_works_ok == 0) && - ((unsigned long)to) < TASK_SIZE) { - /* - * When we are in an atomic section (see - * mm/filemap.c:file_read_actor), return the full - * length to take the slow path. - */ - if (in_atomic()) - return n; - - /* - * CPU does not honor the WP bit when writing - * from supervisory mode, and due to preemption or SMP, - * the page tables can change at any time. - * Do it manually. Manfred <manfred@colorfullife.com> - */ - while (n) { - unsigned long offset = ((unsigned long)to)%PAGE_SIZE; - unsigned long len = PAGE_SIZE - offset; - int retval; - struct page *pg; - void *maddr; - - if (len > n) - len = n; - -survive: - down_read(¤t->mm->mmap_sem); - retval = get_user_pages(current, current->mm, - (unsigned long)to, 1, 1, 0, &pg, NULL); - - if (retval == -ENOMEM && is_global_init(current)) { - up_read(¤t->mm->mmap_sem); - congestion_wait(BLK_RW_ASYNC, HZ/50); - goto survive; - } - - if (retval != 1) { - up_read(¤t->mm->mmap_sem); - break; - } - - maddr = kmap_atomic(pg); - memcpy(maddr + offset, from, len); - kunmap_atomic(maddr); - set_page_dirty_lock(pg); - put_page(pg); - up_read(¤t->mm->mmap_sem); - - from += len; - to += len; - n -= len; - } - return n; - } -#endif + stac(); if (movsl_is_ok(to, from, n)) __copy_user(to, from, n); else n = __copy_user_intel(to, from, n); + clac(); return n; } EXPORT_SYMBOL(__copy_to_user_ll); @@ -637,10 +583,12 @@ EXPORT_SYMBOL(__copy_to_user_ll); unsigned long __copy_from_user_ll(void *to, const void __user *from, unsigned long n) { + stac(); if (movsl_is_ok(to, from, n)) __copy_user_zeroing(to, from, n); else n = __copy_user_zeroing_intel(to, from, n); + clac(); return n; } EXPORT_SYMBOL(__copy_from_user_ll); @@ -648,11 +596,13 @@ EXPORT_SYMBOL(__copy_from_user_ll); unsigned long __copy_from_user_ll_nozero(void *to, const void __user *from, unsigned long n) { + stac(); if (movsl_is_ok(to, from, n)) __copy_user(to, from, n); else n = __copy_user_intel((void __user *)to, (const void *)from, n); + clac(); return n; } EXPORT_SYMBOL(__copy_from_user_ll_nozero); @@ -660,6 +610,7 @@ EXPORT_SYMBOL(__copy_from_user_ll_nozero); unsigned long __copy_from_user_ll_nocache(void *to, const void __user *from, unsigned long n) { + stac(); #ifdef CONFIG_X86_INTEL_USERCOPY if (n > 64 && cpu_has_xmm2) n = __copy_user_zeroing_intel_nocache(to, from, n); @@ -668,6 +619,7 @@ unsigned long __copy_from_user_ll_nocache(void *to, const void __user *from, #else __copy_user_zeroing(to, from, n); #endif + clac(); return n; } EXPORT_SYMBOL(__copy_from_user_ll_nocache); @@ -675,6 +627,7 @@ EXPORT_SYMBOL(__copy_from_user_ll_nocache); unsigned long __copy_from_user_ll_nocache_nozero(void *to, const void __user *from, unsigned long n) { + stac(); #ifdef CONFIG_X86_INTEL_USERCOPY if (n > 64 && cpu_has_xmm2) n = __copy_user_intel_nocache(to, from, n); @@ -683,6 +636,7 @@ unsigned long __copy_from_user_ll_nocache_nozero(void *to, const void __user *fr #else __copy_user(to, from, n); #endif + clac(); return n; } EXPORT_SYMBOL(__copy_from_user_ll_nocache_nozero); @@ -700,14 +654,13 @@ EXPORT_SYMBOL(__copy_from_user_ll_nocache_nozero); * Returns number of bytes that could not be copied. * On success, this will be zero. */ -unsigned long -copy_to_user(void __user *to, const void *from, unsigned long n) +unsigned long _copy_to_user(void __user *to, const void *from, unsigned n) { if (access_ok(VERIFY_WRITE, to, n)) n = __copy_to_user(to, from, n); return n; } -EXPORT_SYMBOL(copy_to_user); +EXPORT_SYMBOL(_copy_to_user); /** * copy_from_user: - Copy a block of data from user space. @@ -725,8 +678,7 @@ EXPORT_SYMBOL(copy_to_user); * If some data could not be copied, this function will pad the copied * data to the requested size using zero bytes. */ -unsigned long -_copy_from_user(void *to, const void __user *from, unsigned long n) +unsigned long _copy_from_user(void *to, const void __user *from, unsigned n) { if (access_ok(VERIFY_READ, from, n)) n = __copy_from_user(to, from, n); @@ -735,9 +687,3 @@ _copy_from_user(void *to, const void __user *from, unsigned long n) return n; } EXPORT_SYMBOL(_copy_from_user); - -void copy_from_user_overflow(void) -{ - WARN(1, "Buffer overflow detected!\n"); -} -EXPORT_SYMBOL(copy_from_user_overflow); |