Merge branch 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

Pull initial set_fs() removal from Al Viro:
 "Christoph's set_fs base series + fixups"

* 'work.set_fs' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
  fs: Allow a NULL pos pointer to __kernel_read
  fs: Allow a NULL pos pointer to __kernel_write
  powerpc: remove address space overrides using set_fs()
  powerpc: use non-set_fs based maccess routines
  x86: remove address space overrides using set_fs()
  x86: make TASK_SIZE_MAX usable from assembly code
  x86: move PAGE_OFFSET, TASK_SIZE & friends to page_{32,64}_types.h
  lkdtm: remove set_fs-based tests
  test_bitmap: remove user bitmap tests
  uaccess: add infrastructure for kernel builds with set_fs()
  fs: don't allow splice read/write without explicit ops
  fs: don't allow kernel reads and writes without iter ops
  sysctl: Convert to iter interfaces
  proc: add a read_iter method to proc proc_ops
  proc: cleanup the compat vs no compat file ops
  proc: remove a level of indentation in proc_get_inode
This commit is contained in:
Linus Torvalds
2020-10-22 09:59:21 -07:00
52 changed files with 346 additions and 495 deletions

View File

@@ -482,10 +482,6 @@ extern unsigned int fpu_user_xstate_size;
struct perf_event;
typedef struct {
unsigned long seg;
} mm_segment_t;
struct thread_struct {
/* Cached TLS descriptors: */
struct desc_struct tls_array[GDT_ENTRY_TLS_ENTRIES];
@@ -538,8 +534,6 @@ struct thread_struct {
*/
unsigned long iopl_emul;
mm_segment_t addr_limit;
unsigned int sig_on_uaccess_err:1;
/* Floating point and extended processor state */
@@ -783,67 +777,15 @@ static inline void spin_lock_prefetch(const void *x)
})
#ifdef CONFIG_X86_32
/*
* User space process size: 3GB (default).
*/
#define IA32_PAGE_OFFSET PAGE_OFFSET
#define TASK_SIZE PAGE_OFFSET
#define TASK_SIZE_LOW TASK_SIZE
#define TASK_SIZE_MAX TASK_SIZE
#define DEFAULT_MAP_WINDOW TASK_SIZE
#define STACK_TOP TASK_SIZE
#define STACK_TOP_MAX STACK_TOP
#define INIT_THREAD { \
.sp0 = TOP_OF_INIT_STACK, \
.sysenter_cs = __KERNEL_CS, \
.addr_limit = KERNEL_DS, \
}
#define KSTK_ESP(task) (task_pt_regs(task)->sp)
#else
/*
* User space process size. This is the first address outside the user range.
* There are a few constraints that determine this:
*
* On Intel CPUs, if a SYSCALL instruction is at the highest canonical
* address, then that syscall will enter the kernel with a
* non-canonical return address, and SYSRET will explode dangerously.
* We avoid this particular problem by preventing anything executable
* from being mapped at the maximum canonical address.
*
* On AMD CPUs in the Ryzen family, there's a nasty bug in which the
* CPUs malfunction if they execute code from the highest canonical page.
* They'll speculate right off the end of the canonical space, and
* bad things happen. This is worked around in the same way as the
* Intel problem.
*
* With page table isolation enabled, we map the LDT in ... [stay tuned]
*/
#define TASK_SIZE_MAX ((1UL << __VIRTUAL_MASK_SHIFT) - PAGE_SIZE)
#define DEFAULT_MAP_WINDOW ((1UL << 47) - PAGE_SIZE)
/* This decides where the kernel will search for a free chunk of vm
* space during mmap's.
*/
#define IA32_PAGE_OFFSET ((current->personality & ADDR_LIMIT_3GB) ? \
0xc0000000 : 0xFFFFe000)
#define TASK_SIZE_LOW (test_thread_flag(TIF_ADDR32) ? \
IA32_PAGE_OFFSET : DEFAULT_MAP_WINDOW)
#define TASK_SIZE (test_thread_flag(TIF_ADDR32) ? \
IA32_PAGE_OFFSET : TASK_SIZE_MAX)
#define TASK_SIZE_OF(child) ((test_tsk_thread_flag(child, TIF_ADDR32)) ? \
IA32_PAGE_OFFSET : TASK_SIZE_MAX)
#define STACK_TOP TASK_SIZE_LOW
#define STACK_TOP_MAX TASK_SIZE_MAX
#define INIT_THREAD { \
.addr_limit = KERNEL_DS, \
}
#define INIT_THREAD { }
extern unsigned long KSTK_ESP(struct task_struct *task);