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

2 files changed, 37 insertions, 35 deletions

diff --git a/arch/x86/lib/getuser.S b/arch/x86/lib/getuser.S
index 2cd902e06062..fa1bc2104b32 100644
--- a/arch/x86/lib/getuser.S
+++ b/arch/x86/lib/getuser.S
@@ -37,10 +37,19 @@
 
 #define ASM_BARRIER_NOSPEC ALTERNATIVE "", "lfence", X86_FEATURE_LFENCE_RDTSC
 
+#ifdef CONFIG_X86_5LEVEL
+#define LOAD_TASK_SIZE_MINUS_N(n) \
+	ALTERNATIVE __stringify(mov $((1 << 47) - 4096 - (n)),%rdx), \
+		    __stringify(mov $((1 << 56) - 4096 - (n)),%rdx), X86_FEATURE_LA57
+#else
+#define LOAD_TASK_SIZE_MINUS_N(n) \
+	mov $(TASK_SIZE_MAX - (n)),%_ASM_DX
+#endif
+
 	.text
 SYM_FUNC_START(__get_user_1)
-	mov PER_CPU_VAR(current_task), %_ASM_DX
-	cmp TASK_addr_limit(%_ASM_DX),%_ASM_AX
+	LOAD_TASK_SIZE_MINUS_N(0)
+	cmp %_ASM_DX,%_ASM_AX
 	jae bad_get_user
 	sbb %_ASM_DX, %_ASM_DX		/* array_index_mask_nospec() */
 	and %_ASM_DX, %_ASM_AX
@@ -53,15 +62,13 @@ SYM_FUNC_END(__get_user_1)
 EXPORT_SYMBOL(__get_user_1)
 
 SYM_FUNC_START(__get_user_2)
-	add $1,%_ASM_AX
-	jc bad_get_user
-	mov PER_CPU_VAR(current_task), %_ASM_DX
-	cmp TASK_addr_limit(%_ASM_DX),%_ASM_AX
+	LOAD_TASK_SIZE_MINUS_N(1)
+	cmp %_ASM_DX,%_ASM_AX
 	jae bad_get_user
 	sbb %_ASM_DX, %_ASM_DX		/* array_index_mask_nospec() */
 	and %_ASM_DX, %_ASM_AX
 	ASM_STAC
-2:	movzwl -1(%_ASM_AX),%edx
+2:	movzwl (%_ASM_AX),%edx
 	xor %eax,%eax
 	ASM_CLAC
 	ret
@@ -69,15 +76,13 @@ SYM_FUNC_END(__get_user_2)
 EXPORT_SYMBOL(__get_user_2)
 
 SYM_FUNC_START(__get_user_4)
-	add $3,%_ASM_AX
-	jc bad_get_user
-	mov PER_CPU_VAR(current_task), %_ASM_DX
-	cmp TASK_addr_limit(%_ASM_DX),%_ASM_AX
+	LOAD_TASK_SIZE_MINUS_N(3)
+	cmp %_ASM_DX,%_ASM_AX
 	jae bad_get_user
 	sbb %_ASM_DX, %_ASM_DX		/* array_index_mask_nospec() */
 	and %_ASM_DX, %_ASM_AX
 	ASM_STAC
-3:	movl -3(%_ASM_AX),%edx
+3:	movl (%_ASM_AX),%edx
 	xor %eax,%eax
 	ASM_CLAC
 	ret
@@ -86,29 +91,25 @@ EXPORT_SYMBOL(__get_user_4)
 
 SYM_FUNC_START(__get_user_8)
 #ifdef CONFIG_X86_64
-	add $7,%_ASM_AX
-	jc bad_get_user
-	mov PER_CPU_VAR(current_task), %_ASM_DX
-	cmp TASK_addr_limit(%_ASM_DX),%_ASM_AX
+	LOAD_TASK_SIZE_MINUS_N(7)
+	cmp %_ASM_DX,%_ASM_AX
 	jae bad_get_user
 	sbb %_ASM_DX, %_ASM_DX		/* array_index_mask_nospec() */
 	and %_ASM_DX, %_ASM_AX
 	ASM_STAC
-4:	movq -7(%_ASM_AX),%rdx
+4:	movq (%_ASM_AX),%rdx
 	xor %eax,%eax
 	ASM_CLAC
 	ret
 #else
-	add $7,%_ASM_AX
-	jc bad_get_user_8
-	mov PER_CPU_VAR(current_task), %_ASM_DX
-	cmp TASK_addr_limit(%_ASM_DX),%_ASM_AX
+	LOAD_TASK_SIZE_MINUS_N(7)
+	cmp %_ASM_DX,%_ASM_AX
 	jae bad_get_user_8
 	sbb %_ASM_DX, %_ASM_DX		/* array_index_mask_nospec() */
 	and %_ASM_DX, %_ASM_AX
 	ASM_STAC
-4:	movl -7(%_ASM_AX),%edx
-5:	movl -3(%_ASM_AX),%ecx
+4:	movl (%_ASM_AX),%edx
+5:	movl 4(%_ASM_AX),%ecx
 	xor %eax,%eax
 	ASM_CLAC
 	ret
diff --git a/arch/x86/lib/putuser.S b/arch/x86/lib/putuser.S
index b34a17763f28..0ea344c5ea43 100644
--- a/arch/x86/lib/putuser.S
+++ b/arch/x86/lib/putuser.S
@@ -33,12 +33,19 @@
  * as they get called from within inline assembly.
  */
 
-#define ENTER	mov PER_CPU_VAR(current_task), %_ASM_BX
+#ifdef CONFIG_X86_5LEVEL
+#define LOAD_TASK_SIZE_MINUS_N(n) \
+	ALTERNATIVE __stringify(mov $((1 << 47) - 4096 - (n)),%rbx), \
+		    __stringify(mov $((1 << 56) - 4096 - (n)),%rbx), X86_FEATURE_LA57
+#else
+#define LOAD_TASK_SIZE_MINUS_N(n) \
+	mov $(TASK_SIZE_MAX - (n)),%_ASM_BX
+#endif
 
 .text
 SYM_FUNC_START(__put_user_1)
-	ENTER
-	cmp TASK_addr_limit(%_ASM_BX),%_ASM_CX
+	LOAD_TASK_SIZE_MINUS_N(0)
+	cmp %_ASM_BX,%_ASM_CX
 	jae .Lbad_put_user
 SYM_INNER_LABEL(__put_user_nocheck_1, SYM_L_GLOBAL)
 	ASM_STAC
@@ -51,9 +58,7 @@ EXPORT_SYMBOL(__put_user_1)
 EXPORT_SYMBOL(__put_user_nocheck_1)
 
 SYM_FUNC_START(__put_user_2)
-	ENTER
-	mov TASK_addr_limit(%_ASM_BX),%_ASM_BX
-	sub $1,%_ASM_BX
+	LOAD_TASK_SIZE_MINUS_N(1)
 	cmp %_ASM_BX,%_ASM_CX
 	jae .Lbad_put_user
 SYM_INNER_LABEL(__put_user_nocheck_2, SYM_L_GLOBAL)
@@ -67,9 +72,7 @@ EXPORT_SYMBOL(__put_user_2)
 EXPORT_SYMBOL(__put_user_nocheck_2)
 
 SYM_FUNC_START(__put_user_4)
-	ENTER
-	mov TASK_addr_limit(%_ASM_BX),%_ASM_BX
-	sub $3,%_ASM_BX
+	LOAD_TASK_SIZE_MINUS_N(3)
 	cmp %_ASM_BX,%_ASM_CX
 	jae .Lbad_put_user
 SYM_INNER_LABEL(__put_user_nocheck_4, SYM_L_GLOBAL)
@@ -83,9 +86,7 @@ EXPORT_SYMBOL(__put_user_4)
 EXPORT_SYMBOL(__put_user_nocheck_4)
 
 SYM_FUNC_START(__put_user_8)
-	ENTER
-	mov TASK_addr_limit(%_ASM_BX),%_ASM_BX
-	sub $7,%_ASM_BX
+	LOAD_TASK_SIZE_MINUS_N(7)
 	cmp %_ASM_BX,%_ASM_CX
 	jae .Lbad_put_user
 SYM_INNER_LABEL(__put_user_nocheck_8, SYM_L_GLOBAL)